Playmate Volley tennis ball machine: Extended Review

[AndI]

1. Introduction.

I spent several weeks researching ball machines before buying one. While I understand and appreciate the benefits of plastics in modern manufacturing and the reasons why the majority of ball machine manufacturers use plastic parts, I was attracted by the all-metal design of the Volley, its professional look, and its stellar reviews from the owners. Ultimately, I decided to “bite the bullet”, bought a Volley, and – for the benefit of those who are on the same quest for the best (for their needs) ball machine – decided to put together this review.

I want to make it as detailed as possible. I will publish it within the next month or so, one piece at a time. Here is the plan: I will start with basic parameters – size, weight, convenience of transportation, controls, etc. At the end, after I accumulate more experience with the machine, I will discuss my personal experience and the degree to which this machine met my expectations and needs.

The other owners of the Volley are welcome to contribute and add what I could have missed.

2. Who makes the Volley and how much it costs.

The manufacturer of Playmate Volley is Metaltek, a family-owned small business founded in 1973. Type their name into Google, and you’ll find that they operate out of approximately 10,000 square feet building in Morrisville, North Carolina, where they design and build their machines. According to Manta and WhereOrg, Metaltek employs 10 to 19 people and has annual revenue of $2.5 to 5 million. Their primary business are plug-in ball machines for tennis clubs. They appear to heavily dominate in this market segment: almost every club has one or several Playmate ball machines. They are known as exceptionally reliable and long-lasting pieces of equipment which can withstand any use and abuse. Phrases like “built like a tank” are frequently found in reviews of these machines.

Playmate Volley clearly shares the same design principles and heritage as more expensive club-level machines, but it is smaller and lighter. The current Volley is its second generation. I had difficulties finding out when the first generation and the second generation were brought to the market. It appears that the current, second generation, was introduced some time between 2005 and 2007. I called Metaltek and asked them if they had the next generation “in the works”. I was assured that there are no plans to change anything any time soon and there is nothing on the “drawing table” for at least several more years.

Judging by the serial number of my unit, Metaltek so far shipped less than 5,000 Volleys. This explains two things: why there are so few reviews of the Volley, and why it is so hard to find a used unit.

The current MSRP of the Volley (as of summer of 2014) is USD 1,990. Some internet resellers ask for prices higher than MSRP, I saw numbers up to $2,195. Rarely, one can find modest price breaks slightly below MSRP.

Metaltek does not sell directly to the public over the internet; they prefer to go through a limited number of authorized resellers who also form a network of local technical support centers. They run their production based on demand and appear to build to order, at least during summer months. The lead time for my machine was quoted as 1-2 weeks until shipment from the manufacturer in NC to the local rep in my area, but ended up being about 1 week.

I checked Craigslit and E-Bay for a used machine, only to find that there is about one used Volley offered on E-Bay once every three months. Old (sold) listings suggest that they keep their value really well. Here are sold listing which I found and which convinced me that a Volley can be sold for half of its price even after 10 years of use – meaning that it is a good investment in the "world of portable ball machines":

April 19, 2014: E-Bay, first generation Volley $1025 + $104.31 shipping.
March 24, 2014: E-Bay, 10+ years old first generation Volley, $825 + shipping.
Sept 17, 2013: E-bay in UK, used second generation Volley, GBP 1,251 (USD 2,096)
April 2012, this forum: $1100 for 3 year old Volley model
(in comparison to the first 3 listings, someone got a really good deal with this offer – no wonder it was sold in just a couple of days).

(to be continued)

 

[AndI]

3. Official Specifications.

Official specifications on the Playmate tennis website are as vague and non-descriptive as one can imagine. There is no chance to compare the Volley's spec with those of Lobsters, Tennis Tutors, or Silent Partners line by line. All you get is this:

• Non-memory, Removable Battery-Pack System (4-6h)
• SMART Charger
• Holds 200 Balls
• Variable Electronic Ball Speed and Feed Rate
• Variable Topspin & Backspin
• Commercial Pitching Wheels Pitch All Balls (Old OR New)
• Manual Height Control
• Integrated, Sliding Ball Hopper
• Aircraft Aluminum Construction
• 2 Year Limited Warranty
• Light-weight at 46 lbs*
• 2-Line Oscillator with Variable Electronic Width & Programmable Random Left OR Right
• Commercial Remote Control

Note that there are only three numeric values in the spec: battery run time (4-6 hours), ball hopper capacity (200 balls), and weight (46 Lbs). The weight number will confuse almost anyone. Note that little asterisk next to 46 Lbs. It is supposed to be a reference to a footnote which did not make it to the Playmatetennis web site (or at least I could not find it). It takes just a couple of measurements on the scales (see Sec. 5 below) to figure out that the footnote was supposed to say “weight without the battery”. Since the battery is almost 16 Lbs, the total weight of the Volley with the battery is 62 Lbs. Note that ball machines from other manufacturers have internal battery, and (I am guessing here) they specify weight with the battery!

There are no official specs for ball speed, feed rate, etc. I called Metaltek and asked about the maximum ball speed. I was told that this parameter depends on many factors, including type of the ball, spin, etc., so they cannot provide a specific number and there is no spec.

 

[AndI]

4. Semi-Official Specifications.

It is funny, but it feels like the left hand at Metaltek does not quite know what the right hand is doing. :?

They do not specify maximum ball speed and refuse to provide a number on the phone. However, on page 20 of the manual (available in PDF format from their web site) they state that “Fast” setting of the ball speed corresponds to approximately 70 MPH (112 km/h, or 31 m/s).

This number is consistent with an estimate which is easy to make. The Volley uses throwing wheels which are 6” (15.2 cm) in diameter. The motors are rated at top speed of 4150 RPM. Neglecting (for the sake of simplicity) the fact that the surface of the wheel which comes in contact with the ball is a little curved (i.e., the diameter of the throwing wheel is a little smaller in the center than at the periphery), the circumference of the throwing wheel is 47.88 cm. If we assume that the RPMs of the wheels do not drop substantially when the ball goes through the wheels and leaves the machine, the maximum linear speed at the surface of the wheel at 4150 RPM will be 33.12 meters per second, or 119.2 km/h, which converts to about 74 mph. This is close to the 70 mph number in the manual.

Another not-quite-specified parameters is ball pitching frequency. It is not in the specs, but per manual (page 22), it is variable from 1 to 20 seconds between balls.

 

[AndI]

5. Weight and Dimensions

My Volley was delivered from the manufacturer by FedEx Ground. According to the tracking information, the shipping weight was 81 Lbs and shipping box dimensions were 30”x25”x23".

The machine was packaged in a box upside down (ball hopper at the bottom, wheels up), battery was in a separate box inside the main carton. There was no Styrofoam inside – all packaging and protection was done using crumpled paper.

Using my floor scales, I measured the weight of the battery (in its green aluminum housing) as 15.8 Lbs and weight of the Volley without the battery as 46 Lbs (which matches the specification on playmatetennis site). Hence, the total weight of the Volley with the “6-hour” battery is about 62 Lbs.

The ball hopper on the Volley slides down for storage and transportation. The images below show all dimensions, with ball hopper in the raised and lowered position. Note that the widest point on the Volley is at the very bottom, between the tips of the wheels' axis.

In its storage/transportation configuration (hopper lowered) it is 24 5/8” tall, 18 3/8” wide, and 21” long.

In its “operational” configuration, with hopper raised, it is 30” tall, 18 3/8” wide, and 21” long.

 

[AndI]

6. A peek inside the Volley (Part A)

Lets start from the ball hopper.

At the bottom of the hopper one sees a standard for ball machines black feeding disk. The speed with which this disk rotates determines the speed at which the machine feeds the balls. The disk has four slots into which balls fall under their own weight and weight of the balls above them. Under the ball feed wire, there is opening; once a ball falls into this opening, it gets picked up and ejected by throwing (pitching) wheels.

The hopper of the Volley is almost rectangular in shape. This puts the Volley at a slight disadvantage compared to brands which use bowl-shaped hoppers. The reason is that the weight of the balls in top layers helps balls at the bottom of the hopper to get into slots of the feeding disk. When only about two layers of balls are left in the hopper, the machine may rarely miss a ball. When only one layer of balls left, every now and then that balls do not get into every slot of the feeding disk. This leads to intermittently less regular ball feed at the end.

Two yellow levers on both sides of the hopper operate the locking mechanism which enables one to raise or lower the hopper. You squeeze the levers on both sides and slide the hopper up or down. Once you released the levers, the hopper is locked in the raised or lowered position. It is very sturdy in both position - one can roll or carry the machine with hopper either raised or lowered, it makes no difference.

Now, lets look into the machine from the front.

In the top right corner of the opening we see the motor which rotates the feeding disk. On the left-hand side, there is a thin but long and wide electronics box. It is surprisingly large compared to the size of the opening on the side of the Volley where the power switch and controls are. Finally, in the center, there are two 6" pitching wheels. These wheels can be better viewed from under the machine.

From this angle, we get a good view of the 6" wheels on the front and 4" lockable casters installed at the rear of the machine, and "under the hood" we again see 6" pitching wheels, electronics unit, and oscillator.

 

[AndI]

7. A peek inside the Volley (Part B)


Looking at the pitching wheel from the side, one notices that the wheel is made of two types of material. The core is the dark yellow plastic, but the surface that touches the balls is made of a lighter shade of yellow material, which I assume is urethane. Actually, it is not just a surface coating but a fairly thick ring (you can click on the thumbnail to get a better view).

When I was picking up my Volley from a local rep, I had a chance to see pitching wheels from a commercial (plug-in machine). They share exactly the same dual-layer design, look exactly the same, but appear to be slightly bigger (I am guessing that the plug-in machines have about 8" wheels).

Finally, a closer look at the motor reveals that it is a 12V DC motor which generates 0.13 HP (almost 97 W) of power or 32 Oz-In of torque and has the maximum speed of 4150 RPM. When it runs at full load and produces 97W of power, each motor should draw 8 Amps of current (I=W/V), but I do not think this ever happens under normal conditions because at 8 Amps per motor, plus some current for the other electronics, would result in 17 Amps in total. This would completely drain the battery in about 45-50 mins.

The logo on the motor suggests that it was produced by a Chinese company Nanjing Fastech Electrical company (Fastechcn). However, I was not able to find this specific part, FF1.0, on the manufacturer's web site.

An interesting thing to note is that there are only two wires coming out of the motor. This indicates that this is an old-school brushed motor (brushless motors have at least 3 wires, sometimes more). Brushed motors have two disadvantages: they consume significant current even when they spin without load (brushless motors are better capable to adjust the current as needed, which makes them more energy efficient), and brushes may wear out over the time. The design of the motor appears to be sealed, which suggests that brushes might be not replaceable. Since brushless motors started gaining acceptance just recently and they generally cost more (including controllers), it is likely that other brands of ball machines use similar brushed motors.

 

[AndI]

8. Remote control.

Volley's remote turned out to be smaller than I thought. It easily fits in a pocket, in a palm of your hand, etc.

It has just one button which starts and stops ball feed and red LED which lights up when the button is pressed. I think the purpose of the LED is to show that the battery is not dead. The button at first glance looks like a membrane switch, but it is not - there is a real mechanical switch behind it.

The remote is powered by CR2032 3V "button" battery. Metaltek/Playmate provides a spare one in a bag with the warranty card and manual. Replacing the battery is not rocket science, but it can be a challenge for a housewife not familiar with a screwdriver. In order to replace the battery, one has to remove two screws in the back and open the housing.

When one lifts the bottom cover off the housing, one does not see the battery yet as it is on the other side of the PC board. A technically oriented person, however, will notice that the remote uses the XBee Series 1 (802.15.4) transmitter ($19 - $25 retail) installed on top of a fairly simple controller board. XBee S1 transmitter has 1 mW output power and is rated for the range up to 100 Ft (30m) in indoor / urban conditions, and up to 300 ft (90 m) outdoors. It operates in the 2.4 GHz ISM band which can be used license-free worldwide. The advantage of this high frequency is that one gets decent range at very low power level. The drawback is that this is the same band in which modern wireless routers, cordless telephones, and microwave ovens operate. Consequently, the range can be adversely affected by interferences from devices emitting in the same frequency band.

Finally, when one lifts the PC board, on its other side there is a battery, the LED, the switch located under the button, and a small controller.

I intentionally do not discuss my personal impressions from remote's size, convenience, and range in this section. I will go into these details closer to the end of my review. However, you can readily relate the range of this transmitter to the range of your home Wi-Fi router or cordless phone.

 

[AndI]

9. Lead-Acid batteries primer.

Before we start talking about battery and charger, a short primer on lead-acid batteries can be helpful to understand what all these charger features mean.

Lead Acid batteries come charged from the factory. Typically, the highest capacity of a new battery is achieved after the battery is cycled a few times or after float charging it for a month or two (we will touch upon float charging in the "charger" section). Once the capacity reaches its peak, it starts gradually degrading over time.

Each battery has a specified capacity (the amount of charge which it can store), but in reality the capacity depends on the current at which it is discharged. Typically, manufacturers specify capacity under the conditions of 20 hour discharge. Slower discharge increases the capacity, faster discharge reduces it. At a 5 hour discharge rate (which is a more reasonable number for a ball machine use), the capacity drops to about 85% of its nominal capacity. Under this conditions, a battery rated at 17 Ah capacity (which is the capacity of the battery in the Volley) drops down to 14.5 Ah.

Lead acid batteries do not like deep discharge as it causes sulfation and can significantly shorten battery’s life. Lead acid battery can survive 1200 charging cycles if it is discharged to 70% remaining capacity, about 450 cycles if discharged to 50%, and only about 200 cycles if fully discharged. A battery formally reaches its end of life when its capacity drops to 60% of its rated capacity. Hence, it is much better for the durability of the battery if it is charged after every use even if the battery is still 2/3 full.

[Added May 2015: Lead acid batteries also totally do not like to remain partially discharged for any extended period of time. They tend to start sulphating (which means, sulphate crystals start growing on their plates) at the moment when their charge drops below 100%. It is just they way they work, as they discharge, chemical reaction inside creates sulphates which can precipitate; charging dissolved them again. You have to charge the battery as soon as possible after use, or it will start losing capacity. Even 24 - 48 hours delay with charging may cause battery degradation. I added this paragraph in May of 2015, and I learned this hard way: after I did not plug it the battery into charger last fall and kept it uncharged (I think at the 2 blinks level) for 2 days, it did not come back to the state which I got used to. The correlation of cause and effect was immediate and clear. Sometimes, I get only 3 blinks on freshly charged battery, rarely 4 blinks, and never 5. I ordered a replacement battery at the end of May of 2015. BatteryMinder charger with desulphation (discussed below) could have been an alternative route, but a new battery was cheaper, so I settled on that path.]

(This is where the Volley's battery which can be quickly and easily disconnected from the ball machine is advantageous - it is much easier to take a small box with the battery into the house to connect it to the charger than bringing in the whole machine)

For the same reason, lead acid batteries should not be stored discharged. Battery voltage should be kept at not less than 2.10 V per cell (12.6 V per battery) when the battery is stored and it must be charged at least once per 6 months. If a charger support correct float voltage charging (2.25-2.3 V/cell (13.5 – 13.8V) when ready), a battery can be left connected to the charger all the time.

Lead acid batteries have no memory effect. It is just the opposite to NiCd batteries. It is very detrimental to discharge lead-acid batteries completely (basically, full discharge will kill the battery), but there is no harm if they are disconnected from the charger before they are fully recharged.

Lead-acid batteries should be stored at 68 F (20C) or lower, if possible. They should be recharged as soon as possible after each use.

One of the ways of determining state of charge of a lead acid battery is by measuring its open circuit voltage. Open circuit (no load) voltage decreases proportionally to the remaining capacity.

A tricky part is that when the battery is connected to a “smart” charger which supports float voltage of 13.7 – 13.8 Volts, the voltage on battery’s terminal will also show about 13.8 Volts when battery is disconnected from the charger. This is the so called “surface charge” which dissipates on its own within 2-12 hours, or disappears within minutes under load. After half a day of storage, voltage drops to about 13V, which is the voltage expected for 100% charged batteries.

I made some measurements of open circuit voltage to correlate it to blinks on the Volley. I found that 5 blinks correspond to the “surface charge” voltage above 13 V. One can see 5 blinks on a battery which was just recently disconnected from the charger, but (as expected) this surface charge disappears quickly and the Volley switches to 4 blinks as soon as the voltage drops to about 12.97 – 13.0 Volts. This happens in about 15-25 mins of ball machine operation (or less) but still corresponds to the nominally 100% charge state of the battery. Consider this little extra charge a bonus for keeping the battery connected to the charger until the very last moment.

(to be continued)

 

[AndI]

10. Battery (Part A).

Volley’s “extended” “4-6 hours” battery comes in a very well made aluminum housing which can be quickly and easily unplugged and removed from the machine for charging. The weight of the battery and housing is 15.8 Lbs.

 

[AndI]

10. Battery (Part B).


Inside of the housing, there is a “High Cycle” 12 V, 17 A-H battery manufactured by a B.B. Batteries. B.B. Batteries is a Chinese company, but is considered sort of a "brand name" of the Chinese manufacturers and costs more than similar batteries from cheaper suppliers. The battery is connected in series with an automotive fuse hidden inside the case. If the battery completely fails, the first troubleshooting step is to check the fuse inside of the housing

B.B.Batteries is a Chinese company which targets higher end, more expensive segment of batteries. They specialize in VRLA batteries, which is just one of possible designs (a battery with a special self-sealing ventilation valve). Their technology is also referred to as AGM (Absorbent Glass Mat).

The battery fits the housing quite tightly. The specs for the OEM battery are as follows:

B.B.Battery EP17-12, nominal weight 13.67 Lbs (battery alone), dimensions 181 mm L x 76 mm W x 166 mm Th (7.13” x 2.99” x 6.54”), with B1 terminals. It is rated at 17 Amp-H under 20 hours discharge condition, but the capacity drops to 14.5 Ah under 5 hour discharge conditions. It retails for around $49 - $55.

When time comes to replace the battery, one can potentially upgrade this battery to a (harder to find) EVP20-12 (about $63 - $80), which has exactly the same form factor but 17% higher capacity. A lower end battery from the same manufacturer would be BP12-17. Replacement of battery requires only a small wrench (likely metric, because the screw is supposed to be M5) and a screwdriver.

UPDATE SEPT 2015: After I discharded my OEM battery to a fairly low remaining charge level and failed to promptly recharge it, I noticed a degradation in capacity and initial voltage. I was no longer getting 5 flashes, and sometimes even 4 flashes did not last longer than a few minutes. I ended up replacing the battery with BP EVP20-12, as I suggested above. I can confirm that this larger capacity battery "fits like a glove" and that replacement is very easy. Since you can completely unplug the battery in the Volley, there is no risk of damaging sensitive electronics in the ball machine itself (a known issue with some other brands). For those who are not confident about their battery replacement skills, there is also an option of purchasing a replacement / additional battery pack from an authorized dealer (see below).

There are many batteries with the same form factor and B1 terminals from other manufacturers in 17 Ah to 20 Ah capacity range, offered at $40 to $42 range. The key is to make sure that the dimensions match those of the OEM battery exactly as there is no spare room in the battery housing, not even 0.1”. The battery sits in the housing super tight. If the replacement battery turns out to be slightly larger than the original battery, it will not fit. The second key factor to keep in mind is that the battery should have B1 connectors (bolt and nut, M5 bolt).

A replacement 6-hour battery pack (including battery, aluminum case, and connection cable) at the time of this writing was available from Playmate dealers for $175.

Volley nominally comes with a 6-hour battery pack, whereas Half-Volley comes with a smaller capacity and lighter battery. According to Batteryspec web site, Half-Volley must be using a 7.5 Ah battery – same capacity as the standard battery in Silent Partner and SportsTutor / Tennis Tutor. The same BatterySpec site states that Lobster uses 18 Ah batteries (and ranks playtime at 4-6 hours). BatterySpec does not list the Volley’s battery.

The connectors on the battery as far as I can tell are Molex Sabre 44441-2002 with 14-16 AWG pins.

(to be continued; next comes the charger)

 

[AndI]

11. Charger.

Playmate Volley comes from the factory with a Soneil 1205SRJ smart charger which is rated at 100-240 V input and 12 Volt 3 Amp output. This is a fairly high end charger suitable for charging any 12V DC lead-acid battery.

This charger included as a standard feature is a significant added benefit of the Volley. The majority (if not all) of other ball machine suppliers provide only a basic charger which can overcharge and damage the battery if it is left plugged-in for too long, and offer “smart” charger as an expensive option. Judging by visual appearance, Lobster’s optional smart charger is also a Soneil charger, albeit with a different (XLR) connector.

Why is this charger called “smart”? The reason is that lead-acid battery must be charged with constant current at voltage level above its nominal voltage of 12 Volts, but once it reaches its capacity, one cannot continue running a significant current through it without causing internal degradation. “Smart” charger automatically determines the charge state of the battery and adjusts (reduces) the charging current as needed.

The Soneil smart charger features automatic 4-stage charging: pulse mode for desulfation of deeply discharged batteries, constant current bulk charging, cell equalization with gradually reducing current, and "float" with current decreasing to nearly zero. to maintain battery in fully charged state.

This smart charger can be connected to the battery all the time when battery is not in use. This is what both Metaltek/Playmate and lead acid battery manufacturers recommend.

The charger included with the Playmate arrived with a Molex Sabre connector. My best guess is that it is Molex Sabre 43680-2202 plug housing with Molex termination blades 43178.

These chargers are built to last. However, in the unlikely case if it should fail, a replacement charger from Metaltek / Playmate (with the correct connector) is readily available for $175. (Other suppliers, like Lobster, offer what appears to be the same charger at a somewhat lower price, around $150, but with a different (XLR) connector). Component suppliers sell Soneil 1205SRJ for about $76 without the connector (bare wires) [In May of 2015, I saw this charger on the internet for as low as around $50]. One would have to solder the Molex Sabre connector to make it work. Only on one of the sites that I’ve seen there was an option of a custom-installed Molex Sabre for extra $8 - $10 (but in this case, one has to watch for the polarity!).

Update May 2015: I recently learned that there is a more sophisticated type of battery charger which can de-sulphate the battery at any stage of charging, including "float" by applying high frequency voltage pulses to the battery. This helps to dissolve small crystals of sulphates, thus restoring the battery to its full capacity and extending its life. BatteryMinder is one of the chargers which have this feature. Unfortunately, Soneil charger, as far as one can judge from the technical data sheet, uses pulses only for de-sulphation of deeply discharged, nearly dead batteries, but not on slightly degraded batteries. BatteryMinder models designed for AGM (Absorbent Glass Mat) technology batteries, such as the one used in the Volley, cost $80 - $130, i.e., more than the Soneil charger. It is a pity that the Volley does not come with one of these chargers. Reviews on the internet suggest that they work well and do extend the battery life.

 

[AndI]

12. Transportation in a car.

The Volley fits easily in an SUV. It may not be obvious from pictures of the Volley which can be found in the Internet, but the most natural way to load it into the trunk is in a horizontal position (face down). This is convenient because the Volley has two handles (as one can see in the second image), so one grabs it by these handles and gets it into the car.

I tried to fit it into the trunk of a medium size sedan, my co-workers Honda Accord, and it did not fit. It was too wide for the opening of the trunk. I am reasonably confident that it would fit on the rear seat, but we did not try.

(to be continued. Next - rolling it to the court and on court)

 

[AndI]

13. Transportation to the court and on the court.

The way how Playmate Volley should be moved around is not self-evident, but once you figured it out, it makes perfect sense and is very convenient.

The Volley has a handle on its back side. Actually, it has two handles, at the bottom of the machine and close to the top of the hopper, but now we are talking only about the top handle. If you need to move the machine from one side of the court to the other, the most convenient way to do it is to pull machine behind you. You cannot push the Volley because in that case casters (smaller wheels in the rear of the Volley) tend to drift around and the Volley does not roll along a straight line which is rather annoying. Pulling works great.

If you need to transport it a longer distance (such as from your car to the court), you tip it over the front wheels and roll it behind you in a tilted position. In this configuration, it can go over both paved and unpaved surfaces. You can roll it over small bumps, but you cannot roll it over stairs - the tilted position does not work well with stairs, and "road clearance" is not sufficient. Grass and gravel surfaces are OK.

It feels better balanced without the battery, but if you do not have helpers, it is more practical to roll it with the battery attached to the Volley. The battery creates a "counterbalancing weight" which tends to flip the Volley to a vertical position if you do not tilt it enough. Usually, it is not a big problem for anyone except the tallest basketball players

If you are tall, you are better off moving the volley around with the hopper in the raised position, those who are short might like the hopper down position.

(to be continued; next: battery life; operation on the court; warranty; comparison with other manufacturers)

 

[AndI]

14. Battery run time.

This is really interesting stuff !

Obviously, manufacturers of all ball machines pick the most favorable conditions to report the longest "on court" time possible. Typically, users of any ball machine find that the court time is shorter than the number promised by the manufacturer. How much shorter and what does it depend on? It is quite difficult to answer this question by just running the machine until you run out of battery because, well, you usually do not practice for that long, and because you may want to change the settings in the middle. However, there is a more unbiased and straightforward way of getting to a specific number. You get a gauge to measure DC current (the picture below shows a very basic analogue current gauge), a few wires, and a couple of appropriate Molex connectors. You crimple or solder the wires while minding the polarity, plug it in between the battery and the machine, and measure how much current the machine draws at different settings. The rest is a matter of math.

Several observations:

1. The current increases with ball speed. This is obvious as motors spin faster. What is not obvious, is how significantly the current increases: it doubles from setting 4 to setting 10 (the scale is 0 to 10, 10 corresponds to approx 70-75 mph).
2. Ball feed adds quite a bit to the current consumption. Each time the machine "spits out" a ball, RPMs of the motors drop, and the current shows a spike (transient) until the RPM gets back to target. I cannot integrate the current over time with a basic amp-meter, so in my table I estimated an average current as a number half way between the spike value and the equilibrium value.
3. Spin does not increase current consumption. In contrast, it reduces it by about 10% to 15%. Evidently, this is because one motor spins slower. However, since one would likely slightly increase the ball speed with higher spin, it is a wash. I'd say, for all practical reasons, spin has no impact on battery life time.
4. Oscillation would likely increase the current, but I did not bother measuring by how much. I am guessing, some 10-20% is reasonable.
4. When machine idles (does not feed the balls), it still consumes a significant current (around 2/3 of the current which it draws when it feeds balls). I was surprised by how much it actually burns when it idles.

In the table below, I listed measured current values for several settings of ball speed, with ball feed on and off. The column in grey is the so called discharge rate - length of time during which the nominal capacity of the battery would be exhausted at this current. As we discussed in the "lead acid battery primer" section, nominal battery capacity (17 Ah for the volley) is defined for 20 hour discharge rate. It drops at a higher discharge current. I estimated the actual capacity of the battery for each specific discharge rate in column 5 (there are tables of battery capacity for different discharge rates provided by manufacturers). Note that at a current which the ball machine draws, you do not get anywhere close to the nominal 17 Ah. Finally, lead acid batteries do not like to be fully discharged. Discharge to 70% is healthy for the battery, discharge to 50% shortens its lifetime somewhat (but not too badly), and discharge to 20% of the remaining capacity is as far as one wants to go without taking risk of ruining the battery.

The last three columns are calculated battery run time for different amount of remaining charge. Compare these numbers to the manufacturer's spec of 4-6 hours. They must have been running the machine at speed 2 without ball feed to get to the 6 hours number.

Clearly, if you crank the ball speed to the highest setting, it will take no time to drain the battery. You will be lucky it it lasts an hour.

Most "normal" people would not need to run the machine at speed 10 or 8. I find that settings between 4 and 6 are good for practice. Obviously, unless you have a helper, collecting balls takes as much time as hitting them. With all this said, we are probably talking about roughly 2 to 2.5 hours on the court until the battery starts getting into the dangerous territory of too little charge left, assuming that you never turn off the machine.

This time can be increased to 3-4 hours on court practice if one turns the machine off while collecting balls. Additionally, if one keeps the battery plugged in into the "smart charger" until the very last moment, one can get some extra 10-25 mins of play off the "surface charge" (another topic discussed in the "lead acid battery primer" section).

Hence, 4 hours of relaxed practice is possible with some stretch with the extended life battery included with the Volley. I cannot readily see how one can get to 6 hours listed in the spec under realistic conditions.

I am still collecting data and the numbers below are subject to change, but so far it looks like 5 blinks corresponds to the "surface charge", 4 blinks is around 100% nominal capacity, change to 3 blinks means you are somewhere between 70% to 50%, 2 blinks is likely 40% to 30% and below, 1 blink means that you are below 20% and are killing the battery by discharging it too deeply.

Please note that the same math applies to any ball machine. I do not think that a Lobster or an SP with the same or similar capacity of extended battery would last any longer on court.

(to be continued)

 

[AndI]

15. Comparison of warranties of ball machines.

When I was doing my research, I compiled the following summary of warranty coverage using information from web sites or in ball machine manuals (listed in the alphabetical order):


Lobster Sports: 2 years (6 months on the battery), non-transferable. The customer has to pay one-way shipment to the repair facility. Extended warranty for up to 3 additional years is available at additional cost.

Playmate (MetalTek): 2 year warranty, non-transferable. Customer is responsible for shipping charges to MetalTek and for the "applicable labor and inspection charges".

Silent Partner: 2 years warranty (no coverage on batteries), non-transferable. 30 days satisfaction warranty (machine can be returned for full refund within 30 days, customer pays for shipment). Customer pays shipment one way to the repair facility. However, if issue can be diagnosed via the telephone and parts can be replaced by the consumer, required parts can be mailed to customer’s home.

SpinFire Sports: 2 year warranty, 6 months on battery. Warranty is administered through a local distributor (mamba tennis in the US). Shipping charges both ways are paid by the owner. Warranty is not transferable.

Sports Tutor (Tennis Tutor). Three year warranty, one year on battery. Warranty is transferable from the original to subsequent owners (as long as the original bill of sale is available). Customer are responsible for shipping the unit one way to SportsTutor for repairs. Extended warranty for 2 more years (excluding the battery) is available for additional fee.


The following things are worth noting. First of all, with about all ball machines, warranty is not transferable and is extended only to the original purchaser. The only exception is Sports Tutor (Tennis Tutor) who offers fully transferable warranty.

The second note is that the text above is a short summary of warranty as published. This is the minimum which suppliers are required to provide. They may, at their own discretion, go above and beyond the stated policy.

I regret to say that, but while Playmate machines may have the best built quality in the industry, their warranty policy (as written) is one of the weakest across all ball machine suppliers. No matter what brand you own, you may have to ship the machine back to the manufacturer for repairs, but no other manufacturer states that the customer must pay applicable labor and inspection charges during warranty period. Owing to the local reps network, one may avoid (significant) shipping charges with the (heavy) Playmate, but inspection and labor fees may still apply. Of course, Playmates have the reputation of tanks and workhorses and they do not break, do they? :?

(to be continued)

 

[AndI]

16. Comparison of features of ball machines.

This is a very dangerous turf... There are many more parameters than ability to throw balls in specific patterns. It is very hard to quantify and compare long term reliability, build quality, noise level, convenience, sensitivity to balls, resell value, etc., etc.

Using an analogy from the automotive world, why would someone drive an Acura, Audi, BMW, Lexus, or Mercedes when one can get the same basic specs and features from a GM or Chrysler, at much lower price? Granted, some features are more important to some people than to the others. When cost is the main and the only factor, every other manufacturer can beat Playmate Volley, some with a wide margin.

Let's see how much one would have to pay to get a set of features somewhat similar to that of Playmate Volley (at least, similar set of drills and basic creature comfort features, such as a remote and a smart charger).

Silent Partner Star is the cost-winner among models similar to the Volley. Just $999 gives you a two-line oscillation, heavy duty battery, and even a remote (some people complain about the grandfather-type technology used in the remote, but this is a different story).

Lobster Elite Liberty has horizontal oscillation, spin control, and manual vertical adjustment. A package with a smart charger and a remote can be purchased for $1167.

Tennis Tutor Plus is the closest in features to the Volley, and it can be aquired for $1554 in a package with remote and a smart charger.

SpinFire Pro 2 is the only model of SpinFire currently available, and it costs $1899 at the time of this writing. It is the only machine (besides Playmate Volley) that has internal oscillation which totally hides in which direction the ball will go. It also has vertical oscillation which the Volley lacks.

When one looks at the summary like this, one thinks: Hmm... There must be something else in addition to the price, some other values that attract buyers... Otherwise, how can prices of different manufacturers differ by as much as factor of 2 ($1000) without all ball machines sales going to the cheapest supplier? :shock:

(to be continued - possibly after the 4th of July holidays. Next: features and operation of the Volley)

 

[AndI]

17. On court operation (Part A)

On-court operation of the Volley is described in sufficient details in the user manual available online. The intention of this section is to complement the manual with several observations and with a few pictures which make it easier to understand how adjustments on the Volley work.

Obviously, you start with bringing the Volley to the court (you can raise the hopper and attach the battery either at your car or on the court). Then, you load the hopper with balls. The nominal hopper capacity is 200 balls, but realistically it feels a little less. The picture below shows the Volley with approximately 165 to 170 balls (three 60-ball boxes minus several cans saved for later). The hopper appears quite full. I can see how one can fit some more balls in it, but this would require manual placement of the balls, as opposed to dumping them from a box.

(to be continued)

 

[AndI]

17. On court operation (Part B).

The Volley has a manual adjustment for ball elevation (or rather angle relatively to the horizontal direction at which the ball is thrown by the wheels; ball elevation also depends on its speed and spin). The adjustment handle is in the rear of the machine, right above the battery. The picture below which is zoomed onto the adjustment handle was taken without the battery. In the bottom right corner of the image, one can see the brackets which the battery sits in, the yellow "button: that fixed it in place and releases it, and the power connector.

It takes several revolutions to go from min elevation to max elevation. There is no indicator of the current setting. I did not find that the lack of indicator was an inconvenience. Since ball trajectory depends on at least 3 parameters (elevation, speed, and spin), I always have to adjust all of them, and I can do it with about 10 balls.

(to be continued)

 

[AndI]

17. On court operation (Part C)

The control panel is very simple to use. The power switch is on the left. The light inside the switch blinks every few seconds to show the remaining charge state of the battery (five blinks is full, one blink is empty). Next to the power switch is the circuit breaker (there is another one inside the battery unit).

Next to the left one finds two small switches. The top one enables one to use the remote to start and stop the ball feed, or do the same thing without the remote. If the switch is flipped to "bypass", the machine starts feeding balls after about 10 seconds delay and would not stop until the machine is turned off or the switch is flipped back to "remote". If it is flipped to "remote", it will not start feeding the balls until the button on the remote is pressed. There is also an audible feedback - two beeps when ball feed is started and one beep when it is stopped.

The bottom small witch is "Random on/off". This is related to 2-line oscillation. The 2-line oscillation feature on the volley is a little different from the 2-line feature on other machines. It is not a random ball placement at any location along the line. It is only two locations. Usually, it will be "forehand/backhand", but it is also possible to use this feature with a narrow setting to add some variability in ball position, or use a wide setting and fast feed rate to feed balls to two people. You can adjust the distance between these two locations from very narrow to opposite sides of the court or anything in between. You can also either program the machine to send balls to each location alternatively (left - right - left - right-...), or do it in a random manner. Since the Volley has internal oscillation, you cannot see or predict where the next ball would go.

In order to switch the 2-line feature off, you reduce the width to zero. There is no separate switch to turn it on/off.

The adjustments for the feed rate, speed, and spin are pretty self-explanatory. These adjustments can be found on all makes and models of ball machines. You can have both top spin and under-spin (down spin).

(to be continued)

 

[AndI]

18. Pre-purchase expectations.

By now, I described almost every imaginable technical detail of the Playmate Volley that can be addressed without taking the machine apart or making precise measurements of ball speed or trajectory with a radar or a video camera. I hope the write-up which I shared so far answers questions which people who follow my path in researching ball machines might have. I had hard times finding enough information on the Volley, and this was the reason why I decided to write it.

The next parts of my review will be more subjective. It may take me several more weeks to finish because I am still gathering “data” (or rather impressions).

I will start with explaining the reasons why I decided to buy Playmate Volley and what my expectations were. In the following posts, I will discuss to which extent these expectations were met.

The requirements / expectations were simple:

1. Solid design and quality of construction. While I understand that first impression can be wrong and probably was wrong, I felt apprehensive about the red and white plastic design of the Lobsters or flimsy appearance of ball hopper design of the Tennis Tutor. I was not thrilled about foldable handles and reportedly weak wheels of many other brands. Playmate Volley attracted me by solid build quality.

2. Established brand. The fact that most tennis clubs use Playmates was a big factor.

3. Consistent performance with any type of balls. I have a seven (almost eight) year old, and I definitely was not going to use pressureless balls (such as Tretorn MicroX) which reportedly feel heavy even for adults and may be way too much for young kids. I needed consistent performance with at least regular balls, and potentially even with Stage 2 (60 ft court) (orange) low compression balls. The Volley manual shows on its cover page the Volley next to a bucket of low compression balls. A call to Metaltek confirmed that the Volley can be used with low compression balls (albeit with a higher risk of jams). I definitely lacked data here, but other vendors' web sites were more likely to explicitly recommend pressureless balls than to indicated that one can use less-than-perfect balls. Playmate was the only one to state explicitly that their machine can be used with any balls.

4. Price was not very important but the resell value was because there was a thought that we may want to sell it in the fall if we do not enjoy (or use) the ball machine enough to warrant keeping it long-term.

5. I wanted to have a consistent ball delivery with little ball to ball variation as I felt that could be important when it comes to working on stroke mechanics.

6. Size and weight were not important at all as we have an SUV... and I am big enough to lift 50-70 Lbs and load it into the trunk.

7. Features and programmability were somewhat important, and I had to compromise here. Many people say they never use drills which are pre-programmed in their sophisticated machines, or they do not work as expected, and even more people say that you work on stokes with a ball machine and work on footwork and ball variability with a live partner. With this, I decided to not go after the most computerized ball machine. Playmate Volley is clearly not the most sophisticated ball machine on the market in this sense, but it has its own good set of features.

8. Battery life and a good (smart) charger was important because I have seen complains about short battery life in ball machines reviews. I did not want to stop my session because I ran out of battery after an hour. Extended life battery was a must.

9. Remote was desirable, and a well working remote with a good range was twice as desirable. There are so many reports that some ball machine brands come with remotes which do not work well or have too short of a range.

10. Large hopper size (ball capacity) was quite desirable. One can load a plug-in machine at a club with 250-300 balls, and this provides a great training session and workout. 100 balls and less feels like not enough. I wanted something in the 100 to 200 range.

11. Predominantly positive reviews from the owners. Playmate Volley has relatively few reviews on the internet, and all of them (or at least all reviews posted by owners of the Volley) are positive. Reviews of other ball machines appear to be more variable.

This combination of factors led to the decision to buy a Volley.

Half-Volley was not even considered because without remote, oscillation, and extended battery it was not worth the money (at least in my opinion). Upgrading Half-Volley to full Volley would cost several hundreds more in the long run than purchasing the Volley from the beginning.

The funny part about this whole story is that my wife was initially convinced that it was the most stupid purchase in my adult life, and buying one of the most expensive ball machines was twice as stupid. That is, she was convinced until she tried it on the court and discovered that it was fun and saw how much it helps her to improve. She seems to like it more and more now. 8)

(to be continued)

 

[AndI]

19. Personal Impressions: Purchasing Experience

Playmates are only sold through authorized online retailers and local representatives. I've seen posts in which people who were considering a Playmate complained that they contacted their local rep and were not happy with the amount of attention which they got. I may have been lucky, but my local rep returned my calls in a timely manner, answered all my questions, offered me the same price that I could get on the internet, and placed the order without prepay. He sent me an e-mail when the unit shipped from North Carolina, and informed me right away when it was delivered to his office. Furthermore, he spent an hour with me explaining how to use the machine (which is very easy, really) and answering my questions about Playmates in general.

The lead time was on the long side. No inventory was available at the rep or at the manufacturer, so I was quoted two weeks lead time to build the machine and one week for shipment. In reality, the unit shipped quicker and I got it in two weeks after the order was placed.

Long lead time was the only downside, otherwise no complains.

(to be continued)

 

[AndI]

20. Personal Impressions: Weight, Size, and Transportation

The Volley without the battery (46 Lbs) weighs pretty much the same as other ball machines with the battery (42-48 Lbs). With the battery, it is quite a bit heavier (about 64 Lbs). To its advantage, it has two big handles which make it relatively easy to lift, carry, and load it into a vehicle. I always transport the battery separately and plug it in only when the Volley is sitting on the ground and ready to be rolled to / on the court. 46 Lbs is within the range which any reasonably fit guy should be able to lift without too much trouble (it is less than the max weight of a suitcase allowed by airlines). The only moment when it feels heavy is a short moment when I load it into the back side of the SUV's trunk when I have to extend my arms while still holding the Volley in the air.

If I did not have an SUV or a hatchback but was driving a sedan, I would be complaining that it does not fit in the trunk.

If I were a petite woman, I probably would also be complaining that this thing is big and heavy.

It is certainly neither the most compact nor the lightest ball machine on the market, but I consider a larger size and weight an indication of a better build quality. While I understand and value the use of plastics in modern manufacturing, one can see how much beefier the construction of the Volley is when comparing 64 Lbs of the Volley with 42-46 Lbs of the other ball machines.

In summary, it is on the big and heavy side, but I do not count this as a drawback. It has that feeling of a serious, well built machine.

(to be continued)

 

[AndI]

21. Personal Impressions: Noise Level.

This is another area where I was impressed with the Volley. I have no personal experience with other portable ball machines. However, I've seen videos where a steady whining noise of a Tennis Tutor ball machine sounded nearly as loud as the voice of the instructor (perhaps camera placement was to blame?). I was a little apprehensive of a thought that my ball machine could be annoying to other people on the adjacent courts, or to residents in nearby houses if I take it to the court very early in the morning. I've seen posts stating that Silent Partner is reportedly quieter than Tennis Tuitor, and that Tennis Tuitor is quieter than Lobster, but have not seen comparisons of the Volley with any other brands.

I can tell that it is very quite. You can barely hear any noise from it from the other side of the court when it idles, and the sound of ejected (pitched) ball is just slightly louder than the sound of a ball hit with a racket. When you push a button on a remote, the Volley makes two gentle beeps when it starts and one beep when it stops. The beeps are audible from across the court, but not annoyingly lound - they sound more like a chime of a washing machine or a beep from a microwave to remind you that your food is hot.

People on adjacent courts may be annoyed by my stray balls or trouble with finding their stray balls among mine, but definitely not by the sounds made by the Volley....

(to be continued)

 

[AndI]

22. Personal Impressions: Remote Control.

This is another easy topic to write about because remote on the Volley works very well.

So far, I used the machine on 6 different public courts. On 5 of them, the remote worked flawlessly, the range was about 2 court lengths, i.e., I could stop and start the machine from a parking lot if I wanted to. On the 6th court located between a high school and a public swimming pool, I had troubles with the range being too short. I attribute it to interferences with WiFi networks in those facilities. As we discussed in one of the sections above, it uses the same frequency band as wireless routers.

I did not feel that remote with only one function (ball feed on/off) is a drawback. I have a short wish list (things which I wish my Volley had...), but multi-function remote is not on it. As long as I can stop the feed, it is not a big deal to walk to the machine and adjust it - and I get an added benefit of seeing what I dialed in for the speed and spin. With just one button, I do not even have to take the remote out of my pocket to use it. I can just reach for it and squeeze it.

The small size of the remote is both its advantage and disadvantage. It may sound weird, but I am afraid that I might lose it because it is so small, or it may drop out of my pocket and I would step on it. It is stupid of course, but now I am thinking about using a soft holder for iPod which wraps around your arm. The remote from the Volley is not much bigger and might fit. Then I would never lose it and would not even need to reach into my pocket.

It would be also nice if the Volley had an area where I could store the remote right on the machine. It happened once or twice that I accidentally forgot the remote at home. You can use the Volley without the remote, but it is kind of a hassle.

Remote is very well integrated into the Volley's operation. There is a switch on the Volley which turns remote control on and off. Usually, it is always on. In the "remotely-controlled" mode, the machine would not start feeding the balls until you press the button on the remote.

Remote is a nice "creature-comfort" feature to have. As one of the authors on this forum once said, a ball machine without the remote is akin to a TV without the remote. I agree.

(to be continued).

 

[AndI]

23. Personal impressions: compatibility with regular (pressurized) balls.

I bought for the ball machine three 60-ball boxes of Penn balls from Costco. I chose those balls exclusively on price. Based on what I read on discussion forums, I did not expect that any balls would last long when used in a ball machine. I will address the ball tear and wear topic separately, but for what is worth, it has been a month and a half of use and I see no reason to replace these balls any time soon. As expected, they lost some of their bounciness from storage at atmospheric pressure, but after playing with the Ultimately Dead Balls (low compression 60-foot court orange balls) on a regular basis they feel wonderfully bouncy.

There were no issues with these basic regular balls whatsoever.

Ball jams - none so far.

(to be continued)

 

[AndI]

24. Personal impressions: compatibility with low compression (orange) 60-ft court "Kids 10 and under" balls.

This was one of the key reasons why I bought the Volley despite its price. I have a 7-year old. In his classes, he is taught tennis with orange low compression balls. He does not like them for the same reason most adults do not like them - as I stated just a few lines above, a good name for them is "Ultimately Dead Balls". However, I can see why USTA implemented them - slower speed and lower bounce can be beneficial for kids. Initially, we used yellow balls when we played on our own, but it did not take long to find that it was hard to adjust back and forth: when one switches from yellow to orange, one almost always hits the net because orange balls require much more hitting power to get them across the court, and when one switches back, one usually overshoots the court. It takes some 15-30 mins to adjust unless you are very skilled with changing back and forth. My son was doing poorly in his classes after practicing with regular balls. So at the end we decided that for him, it will only be low compression to remain consistent.

So, I needed a ball machine which can handle low compression balls. I felt quite apprehensive about taking chances with machines which manufacturers explicitly recommend pressureless balls. This recommendation implies that their machines might not work well even with regular balls, and orange balls might be completely out of the picture. The Volley was the only machine which was shown with low compression balls on the front cover of the manual. A call to Metaltek confirmed that it is considered compatible (although they warned me that the risk of jams is higher with low compression balls). The only balls which cannot be used with the Volley is the initial stage 36-foot court balls which are larger in diameter.

I have less experience (fewer hours on the court) using the machine with orange balls than using it with regular yellow balls, but so far I am very pleased with the result. It works fine, ball throws are consisted, and so far there were no jams with low compression balls!

We use a mixture of Gamma Kids and Wilson 60-ft court orange balls.

Of course, with orange balls and a kid on the court, a typical ball machine setting is from service line to service line with a lower speed. I am guessing that this also helps to reduce the risk of jams with those balls.

(to be continued)

 

[AndI]

25. Personal impressions: battery run time.

You may remember the measurements of the current which Volley draws from the battery which I made in section 14 (scroll up to get to it). That section also had calculations of the estimated run time until 50% or 80% discharge. The conclusion was that battery run time strongly depends on the settings (especially ball speed). It also depends on whether the ball machine is kept on or off while it is idling when the user is collecting the balls. It is not immediately obvious, but the machine burns almost as much current when it idles as when it feeds the balls.

So far, my observations are reasonably consistent with those calculations.

The longest session which I had with the Volley was about 2.5 hours with myself, my wife, and our son. It was the only time in over a month of the Volley ownership when the battery indicator on the Volley was down to 2 blinks at the end of the session.

My usual practice is between an hour and one and a half hours. Typically this translates to about 800 balls fed through the machine with variable settings from baseline to baseline to volleys and overheads. Usually, by the end of the practive the indicator drops to 3 bllinks (on the scale of 1 to 5) and the voltage measures between 12.4 and 12.5 Volts. This indicates that the battery is still between 40% and 50% full.

It is really hard to collect a good statistics because battery discharge rate very strongly depends on the ball machine settings which are rarely the same session to session. However, I can say with a good deal of confidence that the extended battery would last at least 2 hours of adult practice with speed settings around 6-7 (or perhaps 2.5 hours if you decide to discharge the battery into a dangerous (for the battery's longevity) area below 20% remaining capacity), and more than 3 hours for practice with slower ball speed settings (e.g., with kids).

While I know that switching the machine off while collecting balls can significantly extend the battery run time, I rarely use this trick because I know that the battery has more capacity than I need in a single session.

I would guess that the "regular" battery which comes with half-volley (7.5 Ah?) would last only for about an hour with speed in the 6-8 range, which may be barely enough, if not too short. An "extended" battery is therefore a must.

(to be continued)

 

[AndI]

26. Personal impressions: ball to ball variability.

Ball to ball variability is not easy to quantify because many factors contribute to it. I did not bother to take a video, but I watched on a few occasions where the balls land. I used a typical configuration in which ball machine is at the baseline and balls hit the ground around the service line or between service line and base line.

With brand new balls, depth variation (i.e., variability in the direction along the length of the court) was surprisingly good, not greater than +/- one foot. Surprisingly, there was also a variation of position in direction perpendicular to the direction of the court which was on the same scale or slightly greater than variability in depth. Overall, the position where balls land was very reproducible and very accurate.

A month later, with the same batch of balls, depth variability has increased to perhaps +/- 1.5 feet under best conditions and +/- 3 feet under less favorable conditions. The biggest factor affecting variability (with all balls of the same age and wear) turned out to be dirt on the surface of the balls. Our local public courts are not maintained quite as well as pay-by-the-hour courts at the tennis center, and debris from adjacent trees or dirt at the fence washed in by the rain occasionally happen. This dirt easily falls off the balls once they hit the ground a couple of times. However, if dirty balls are loaded into the hopper, contamination on the surface increases the depth and direction variability quite a bit. You load dirty balls - you get several extra feet of variability.

We do not have clay or grass courts in our area, but I might imagine that the odds of getting dirt onto the ball surface is much greater on those courts.

A mix of balls from different batches can increase spread very significantly. Playmate's web site recommends that one can use old OR new balls, but recommends against mixing them. I accidentally picked up several stray balls from adjacent courts (other brand, other condition than mine) and they fly on a noticeably different trajectory; they can bounce higher, and they can land some 4-5 feet off from where the rest of the balls land.

Mixing old and new balls appears to be an established way of adding depth variety. I might try it one day. So far, I've been using balls which were purchased and opened at the same time, and variability remains quite low. Not is perfect as it was with brand new balls, but even after over a months of use the balls land within perhaps +/- 2 to 3 ft or so. I am very pleased with this consistency.

The learning from this is that when one buys a Volley which has a siziable hopper, it is smart to buy three boxes of balls and start using them at the same time. It is not a good idea (unless depth variety is desired) to start with one box and buy more balls later.

(to be continued)

 

[AndI]

27. Personal impressions: setting up ball speed / height / spin.

It usually takes me from 10 to 15 balls to set up the desired ball trajectory. Why so many? For one thing, elevation angle, speed, and spin are interdependent. If you change one of these three parameters, you most likely will have to adjust at least one of the remaining two. You end up going through a couple of iterations of adjustment. The second factor to consider is inertia of the ball machine pitching wheels. At regular feed rate, it takes 2-3 balls for those wheels to accelerate or slow down and stabilize.

The height adjustment is manual. It takes several revolutions from min to max. There is no indicator of where you are (one can peek inside and check at which angle to the horizon the pitching wheel assembly is). I do not consider lack of vertical elevation indicator an issue because I have to adjust all settings through trial and error anyway. The only minor inconvenience is that electronic adjustments can be done nearly instantly, while it takes a few seconds to rotate a manual multi-revolution handle to introduce a significant change. In the worst case scenario, I may spend extra 10 seconds and 3-5 balls to get to where I want it to be elevation-wise. Not a big deal with 180 balls in the hopper.

As I think about it, I do not even want to be able to exactly reproduce my yesterday's settings because I do not want to practice today with the exact same ball speed and height as I did yesterday.

Ball feed rate has a huge range. I usually have it sitting between 2.5 and 3 on the scale of 1 to 10. One has to be a superhuman to be able to hit balls at the feed rate of 10. Even if you have two people with 2-line oscillation, 5-6 is plenty.

Ball speed has - lets say - adequate range. I found that I like it between 6 and 7, and anything above 8 is too fast for me at my current level. However, this judgement is highly subjective - I can see that some people might want to have it higher for the very reason that they want to improve their ability to return very fast balls. In this case they would be approaching the machine's limit.

I did not experiment with spin enough to comment on its range. I usually use moderate top spin. It is clear that if one wants to go to the highest possible ball speed, one also has to go to extreme top spin to avoid overshooting the court.

When it comes to overheads, I found that I can get a decent elevation if I crank the elevation handle to the limit and move the machine closer to the fence, well behind the baseline. It seems that the Volley has some limitations when it comes to lobs as in a workable configuration there is no room left to send balls more vertically. Other brands of ball machines might have the same constraints because their design principles are similar, but I did not have a chance to compare. Although a live person can send a ball much more vertically, it is questionable how valuable it is to practice with such balls.

The controls are very simple and easy to use. They are easy to reach, and of course there are no issues with their visibility under bright light (a known issue with electronic indicators).

(to be continued)

 

[AndI]

28. Personal impressions: 2-line oscillation.

This is a very valuable and useful feature. A ball machine without it would be boring to use. It can serve at least three purposes:

* it enables one to alternate between forehands and backhands
* when width of oscillation is set to a narrow value, one can use it to add small variability to where the ball lands, for either forehands or backhands
* it is a great way to have a cardio workout .

I found that I use 2-line oscillation in at least 80 percent of the time. In fact, you cannot turn it off. You can only reduce the width (angle) to zero.

The machine can throw balls to only two positions. The angle between these two positions is adjustable to any value from zero to the full width of the court.

There is a "random" feature which make the machine to thrown balls left or right in a random pattern. The maximum number of balls which the Volley sends to the same direction that I have seen so far is 3, but it can be 1 or 2. I suspect that the pattern might not be truly random, but it is too complex or long to remember. Due to internal oscillation feature, you cannot see or predict if the next ball will go to the left or to the right. Even if you watch the spinning throwing wheels through the opening in the machine closely, you still cannot predict it because you do not see much of a movement. For all practical reasons, it is truly random.

The Volley can not send balls to random spots anywhere along a line, it is always only two locations. I wish this truly "random-along-the-line" option was available because this would enable one to train not only with shots on one's left or right, but also with random shots some of which could be coming in the direction of one's body, as well as shots with a variable distance to the ball.

(to be continued)

 

[AndI]

29. Personal impressions: ball tear and wear (Part A: loss of compression).

I've seen opinions on discussion forums that balls last very short time in ball machines. Two reasons were given: loss of pressure and loss of fuzz. The reason that was given for a quick loss of pressure was that throwing wheels of the ball machine squeeze the ball so strongly that it forces the air out.

I cannot speak of all ball machines. They may vary with respect to ball longevity. I can only test and share with you my observations with the Volley.

In this part I will address loss of pressure. I have no direct means to measure pressure in the balls, but it is easy to assess bounciness of the balls. I made a simple test. I set up a camcorder in my garage to videotape how balls fall from the ceiling to the concrete floor and how they bounce. Then I converted 60 fps video to frames with balls at the top of their bounce and cropped and merged images into a composite.

The picture below illustrates the set-up. I am about to drop a ball from about 8-9 feet height. The composite image will consist of narrow strips with the ball at the top of its bounce and parts of the door.

I used four groups of balls in the test:

1. Brand new balls (fresh from a sealed can)
2. Balls which were used in my ball machine for 5-6 weeks. I estimate that the balls went through the machine at least 50 times.
3. Balls which were never used in a ball machine; they were in storage for 3-4 months and saw relatively low use.
4. Low compression orange balls, thrown in for comparison to show how balls bounce when they have very low internal pressure.

Groups 1-3 were Penn balls from Costco. Group 4 are almost new Wison orange "kids 10 and under 60 ft court" balls.

A clean experiment would be to compare balls of the same age, which were and were not used in the ball machine. Since I did not plan on this test ahead of time, I did not have such a set to compare.

Two dotted lines in the image are provided as guides for the eye. The height to which balls bounced can be estimated (as a ballpark) from about 4 feet for low compression to about 5.5 feet for new balls.

The conclusion is quite interesting. Balls which were used in a ball machine lost a little bit of their original bounciness, but there was no abnormal loss related to ball machine use. In fact, they are surprisingly bouncy, for their 5-6 weeks age, and bounced nearly as high as new balls. Balls after 3-4 months of storage show visibly less bounciness and much more ball to ball variability, but even at that point they are still way better than the "ultimately dead" low compression balls.

I conclude from this test that significant loss of pressure due to ball machine use is a myth - at least, with the Playmate Volley. Other ball machine may be different.

I was surprised that the result was so good. Three factors could be contributing to it. For one thing, Volley has a big hopper. With 180 balls per load, you do not need to run each ball through the machine as often as with machines with smaller hoppers. (For all practical reasons, it is a wash in the sense that you can buy 50 balls and replace them every 3 weeks or buy 150 balls and replace them after 9 weeks.) The second factor could be that with a bigger size of the throwing wheels used in the Volley (which is a reason why it is so bulky, compared to some other brands) there is no need to squeeze the balls quite as hard. This could also account for compatibility with low compression balls (my son continues using the Volley with low compression balls, still no jams). Finally, balls with less fuzz reportedly fly faster, so balls used in a ball machine might reach a slightly higher vertical speed when they hit the ground; this could slightly offset the loss of bounce.

(to be continued; next: loss of fuzz)

 

[AndI]

29b. Personal impressions: ball tear and wear (Part A: loss of compression: additional comment).

After I posted a summary of my test, I became curious what are the ITF regulations for the ball bounce. Surprisingly, my test which I conceived almost randomly (where can I drop the ball off... ?) was quite close to the official test - with the difference that I did not care to measure the ball bounce height... and it did not bounce off granite...

The official rules and image of testing equipment can be found here, scroll down to "Rebound"

"The rule specifying how the ball should bounce was set in 1925 and is still in use today. The test involves dropping a ball vertically from a height of 254 cm (100 inches) and measuring the rebound, which should (for all Type 2 balls) be 135-147 cm (53-58 inches). The range for balls for use at high altitude is 122-135 cm (48-53 inches).

The equipment used in the ITF laboratory consists of a vacuum pipe that holds the ball at the correct height before being released, a smooth, granite block onto which the ball bounces, and a video camera and light source. Each rebound is recorded and the rebound height measured from the shadow of the ball that is cast against a scale. This is all done with software that analyses the video of the bounce in real time and calculates the height using the contrast between dark (the ball) and light (the background) over a series of frames either side of the peak."

Not that it really matters - people judge ball condition by the feel, not by the number associated with the height to which they bounce - but still an interesting fact for those (like me) who did not know that there was an official test for ball bounce...

(to be continued)

 

[AndI]

30. Personal impressions: ball tear and wear (Part B: fuzz loss)

The role of vitreous felt (fuzz) on the balls was discussed in many internet publications, scientific articles, and even PhD theses. It appears that the most important function of the fuzz (besides its bright yellow color) is to change aerodynamic properties of the ball. A "rough" surface of the ball covered with fuzz creates a higher drag by a combined action of friction between air and fuzz filaments and higher amount of turbulent air flow ("wake") behind the ball. Consequently, balls with fresh fuzz fly slower than balls that were stripped off fuzz. There also were opinions that balls with fresh fuzz is easier to put spin on (due to a better contact with a racket) and they might change their trajectory due to spin to a greater extent (due to a stronger air friction).

Since air inside the ball weighs next to nothing, weight loss which balls show with age can be attributed to fuzz loss. Balls lose fuzz during regular play, when they are hit with a racket or when they land on concrete, and also when they get between spinning wheels of the ball machine.

There were opinions in the forums that balls have very short life span in ball machines because they lose compression and because they lose fuzz. I was prepared to replace the balls within a few weeks, and was happy to see that they last longer than that (granted, I am neither super picky nor eager to buy three more boxes of balls).

International weight limits for tennis balls are from 56 to 59.4 grams. I measured weight of 3 brand new balls and 6 randomly picked balls which I used with the ball machine. Measurements were taken using a laboratory-grade Mettler digital scale.

New balls measured at 58.221 +/- 0.958 grams.

"Ball Machine" balls measured at 57.024 +/- 0.883 grams.

Hence, the balls lost on average 1.197 grams of fuzz due to use with the ball machine. They are still in spec, but they will likely be out of spec after further 4-6 weeks of use if they continue losing fuzz at the same rate.

"Ball machine" balls got a little softer by the feel (as compared with the new balls), but (as described two posts above) retained their bounciness presumably due to partial loss of fuzz.

Visually, you can see that the "ball machine" balls are not quite as "hairy" but still have an adequate surface coverage.

New balls:

"Ball machine" balls, about 6 weeks of use / about 50 times through the machine

The conclusion is that based on bounciness and weight criteria - regular non-premium balls can last for up to 2.5 to 3 months with normal ball machine usage with the Playmate Volley. I already noted in the prior posts that in my experience, the Volley shows very good compatibility with balls of any age, with only moderate increase in ball spread and jam-free operation.

Individual results may vary depending on number of hours per week with the ball machine and acceptance of less-than-perfect balls for practice.

(to be continued)

 

[AndI]

31. Personal impressions: Strengths and Weaknesses of the Volley

It is about time to sum it all up.

Strengths:

* Compatibility with any balls, including new balls, old balls, and low compression orange balls (I attribute it to large diameter, high quality throwing wheels used in the Volley).
* Relatively low tear and wear of the balls used in the machine. In my experience, a set of regular balls would last at least 3 months of regular use. Basically, it is the same lifetime as with balls not used in a ball machine. Partial loss of fuzz compensates for loss of pressure by maintaining bounciness. I see no need to use pressureless balls with the Volley, given a much higher price of those balls and the same fuzz loss over the time.
* Excellent ball-to ball reproducibility with new balls and only a minor degradation with old balls (as long as new and old balls are not mixed and as long as balls are not too dirty).
* Totally jam-free operation. [UPDATE SEPT 2015: After two years of operation, with orange balls and yellow balls ranging from new to up to 5 months out of the cans, sometimes with dirt from the trees on the balls, still not a single ball jam].
* Large ball hopper size (fits 170-180 balls)
* Large wheels and well thought-through location of carrying handles simplify transportation to the court and on the court.
* Detachable battery makes it easy to take inside and plug into the charger. It also makes it easy to replace the battery when it reaches the end of its life span, or to use two batteries for those who use it on court for many hours (e.g., for teaching).
* Sufficient battery life for any reasonable individual training session (2-4 hours depending on settings and use)
* Very quiet operation [UPDATE SEPT 2015: I had two opportunity of watching Tennis Tutor machines on the court. I can tell that the thump that comes from the Tennis Tutor when it throws out the ball is significantly louder than the noise that comes from the Volley. I did not have a chance to compare with other brands, so far].
* Remote and extended life battery are included with the Volley in its standard package.
* Very compact remote with a good range (on the order of 2 court lengths, except in areas with strong Wi-Fi interference).
* Internal rotation completely hides the direction in which the next ball will go in 2D random mode. [UPDATE SEPT 2015: the mechanism in the Volley moves at the moment when it ejects the ball. My son, just for fun, has demonstrated that when he watches the machine instead of the ball, he can see if it changed direction. So, if you try hard, you can see it. However, if you pay attention to the ball, you will never see it].
* Regional sales / service reps network may reduce shipping costs and turnaround time in case service is needed. Field service may also be possible, albeit at a cost.
* Settings are easy to adjust in any lighting conditions.
* Stellar reviews from owners regarding functionality and long term reliability.
* Hitting ball machine with a ball is not a concern - all-aluminum construction can withstand it.
* Audio feedback on on/off: double beep when ball feeding starts, single beep when you turn it off.
* Feel of a quality machine that was built to last.
* Very good resell value.


Partial Weaknesses:

* heavy and bulky (I consider this a partial weakness because its flip side is strength in ball compatibility due to large good quality throwing wheels and another strength - high build quality)
* Manual elevation control is a little bit of a hassle. [UPDATE SEPT 2015: I found over time that you usually do not change it much, if at all]
* Lobs require moving the machine outside of the base line, almost to the fence.
[ADDED SEPT 2015: I learned over time, with practice, that this observation is not entirely true. When it comes to lobs, a lot depends on the direction of the spin. With a proper spin setting, one does not need to move the machine outside of the baseline].
* Official specifications are very limited and in some cases do not match real life observations. For example, actual battery life is much shorter than stated, and hopper capacity is more like 180 balls than 200. To be fair, the “very best case” scenario is typical for how specs are written by all ball machine manufacturers. I doubt that battery lasts longer in other brands.
* Maximum ball speed at around 70 mph is lower than that specified by many other manufacturers (80-90 mph – but who knows if their machines actually meet that spec).



Weaknesses

* The most constrained and the least customer friendly warranty across all ball machines (I have not utilized the warranty and can only judge it based on the language in its disclosure). The way how it is written, no repair is free to the owner: one has to pay for shipping and labor associated with troubleshooting.
* Warranty is not transferable from the original owner.
* Occasionally misses a ball feed when less than 25 balls are left in the hopper.
* Lack of truly random 2D oscillation in the sense of balls landing anywhere between two points.
* Lack of 3D oscillation (side to side plus depth along the length of the court).
* Relatively limited features for the price.
* Lead time for delivery can be long.
* People without SUV or hatchback will find that the Volley does not fit into the trunk.

Neutral observations.

The Volley lacks per-programmed drills and user-defined programmability of a sequence of balls offered by some brands (notably, highest priced Lobster models). I totally do not miss pre-programmed drills because it takes no time to memorize the sequence, after which you will end up running to the next ball even before it leaves the ball machine. This defeats the purpose of the drill. So far, I had no need to be able to program sequences of balls by myself.

Remote has only one button (on/off), and it feels totally sufficient. All adjustments can be done from the machine.

It is possible to use the machine without the remote, but 10 seconds delay is a mixed bag. The idea behind is to give you enough time to get to the other side of the court before ball feed starts. However, if you need to turn the feed on to adjust the settings while you are standing next to the machine, you still have to wait for 10 seconds. It is much better to have a remote at hand than to leave it at home!

(To be continued: two more section to come (further reading and how I use it) - and we are done

 

[AndI]

32. Other reading.

Posts on this forum which I found interesting and bookmarked (this list is by no means all-inclusive, despite my efforts I certainly could have missed some of the equally interesting threads):


Review by kopfan


Review by beldredge


Discussion started by aggielaw


Discussion by GnRFan


Video on YouTube (instructions how to use the Volley posted by a yacht club which owns a Plamate Volley and a tennis court).


In a recent discussion of SpinFire Pro 2, Lobster Elite, and Playmate, kingswild made the following observation which I think is worth citing: "it seems like each of these three machines have seemingly no brainer huge convenience advantages over the others...which I don't get why the others don't implement. Playmate having the removable battery and easily rollable (plus build quality and internal oscillation), spinfire with the 3D mode and internal oscillation, lobster with the random spin & speed." The point here is that there is no perfect machine which meets every expectation.

 

[AndI]

33. How do I use the Volley.

Since I cannot carry (or roll) the Volley, the balls, the ball pick-up hopper, and the racket at the same time, I need to walk from the car to the court at least two times, sometimes even three times. For this reason, I prefer to use courts where I can park as close to the entrance as possible.

Despite good wheels, I find myself lifting and carrying the Volley between the car and the court more often than rolling it. It is not very heavy with battery detached and has good handles.

I am somewhat concerned about creating inconvenience for other people when I use the machine. Inconvenience comes from stray balls which accidentally get on adjacent courts and from ball mix-ups. Noise is never an issue because the Volley is very quite. Ball mix-up is often a concern because when someone else's ball gets on my court, people usually want to find their ball among my 180 balls which all look the same. While it is not exactly my problem, I feel that I created it. In this sense, low compression balls which are orange make life much easier. I do not use Tretorn Micro-X, but those also available in a different color.

When I practice myself with regular balls, I usually do it early in the morning which most players are still sleeping, or try to use a corner court and hit cross-court into a corner. With low compression balls which my son uses, I am not concerned about neighbors at all because nobody else uses orange balls.

People are oftentimes curious about the machine, but never showed any negative attitude.

When it comes to practicing, I was concerned that if I repeat a wrong movement a thousand times, I can "engrave" it in my muscle memory. Therefore, once I got a ball machine, I also started scheduling private lessons from one to three times per week. In each lesson, I would tell the instructor what I worked on with the ball machine and would ask to provide specific feedback on what changed for better and what became worse. I also plan to use video feedback but have not gotten to that point yet.

Ball machine is clearly not a magic solution to improving in tennis, but it is a valuable tool which can be very helpful with improving specific strokes and movements. It definitely helped me to get better in many aspects. It is best used in combination with lessons and with playing with a partner.

Likewise, my 7-year old son had lots of fun with the ball machine since we got it and his skills are also improved. This week, he worked on his top spin.

So far, the Volley has served me well. Would I buy it again or would I buy something different? I really would like to see someone write a review similar to mine on Lobster or Silent Partner or Tennis Tutor or SpinFire. Since in most cases one can't return a ball machine, one has to chose wisely. I had specific requirements to ball compatibility, build quality, and noise level, and I am glad that the Volley has met them all. I do not know if other brands would meet the same expectations.

 

[AndI]

34. Thank you!

I'd like to thank the readers on this forum for their patience and for allowing me to continue adding posts over the last month without interruptions.

I surely hope that this review will help others who are in the market for a ball machine to make the right (for them) choice. One rarely see a Volley on a court, and it is hard to find information on it. This review was supposed to fill this informational gap.

This thread is now open for discussion. If you have comments on the Volley, or can make comparison with your own ball machine using your experience or my description, by all means, please "chime in"!

 

[AndI]

Addendum 1.

I had an interesting learning experience today which was another demonstration of how speed, spin and elevation are interrelated. I set the machine to lobs today and experimented with the spin settings. I usually use a moderate top spin and in the past did not bother to change it when switching to lobs. This time, I changed to to zero and then to modest underspin. I learned that it has a huge impact on how steep and high the balls go. With this change in place, I was able to get balls thrown much steeper and higher and I no longer need to move the machine behind the baseline.

It makes sense: spin is created when wheels rotate with different speed. It is often referred to "counter rotating wheels", which is not a very accurate term because they spin in the same direction, but with different rpms. Evidently, when the upper wheel spins faster, it not only creates a top spin on the ball, but also changes the direction in which a ball is ejected towards lower elevations.

 

[Booger]

HUGE thank you for this thread. It's hard to find anything more than a few sentences when it comes to ball machine reviews. I think I'm going to give the volley a shot.

Now please do the same for the other 3-4 competing machines .

 

[elkwood]

Very comprehensive review for this ball machine. Thanks for taking the time to do this !

 

[NSXER]

Very comprehensive review for this ball machine. Thanks for taking the time to do this !

+1 Well done & written!

 

[neverstopplaying]

Quite an impressive review.

I switched to a playmate machine in 2013 and have nothing but good things to say. I think most people would appreciate the superior build quality vs. The feature-loaded competition. Playmate does not get enough appreciation on tt.

 

[kailash]

WOW! Awesome and very comprehensive review; never seen such an impressive and detailed review.

A big thank you!!

 

[COPEY]

http://tt.tennis-warehouse.com/showpost.php?p=8496167&postcount=11


The cheapest place I've found to purchase a replacement charger: http://www.batterystuff.com/battery...rs/220vac-input-12-volt-output/son1205sr.html

Oh and yes, awesome review!

 

[LakeSnake]

Has anyone used older versions of this machine? My club has a very similar device, except it has no "Speed" knob, just one Forward and one Backward spin knob, collected under a single title of Speed. It seems that varying the speed is somehow achieved by mixing or balancing these two knobs, but I have not really figured out how to do it. I would prefer to be able to dial in some relatively flat, moderate pace balls. If anyone has any advice, I'd love to hear it.

 

[TorontoTennis]

Thank you so much for posting this review. I don't think I have ever read a review of any product, let alone a ball machine, that was so detailed and written by someone whom you could tell really knows what he is talking about. It's obvious that you must be in a technical field, either engineer or scientist.

I got introduced to a ball machine on my last trip to Florida when I rented one on a city court that had a club attached. And yes the machine was indeed a Playmate.

I am currently debating whether to buy a Silent Partner Smart Battery-only ball machine to use during my flexible work-day in one of 8 courts that are only a block away from my home, in between a once a week tennis lesson and playing singles and doubles tennis with a partner.

I know this doesn't apply to most people on this forum, but I happen to be partial to the SP Smart mainly because of my geographical location here in Toronto, Canada which is just a stone's throw from Deuce Industries who manufacture the Silent Partner series of ball machines. They are known for providing absolutely top quality customer support and repair parts availability. They also told me that most parts are replaceable by the user but some cannot be and when that is the case even for out-of-warranty machines they will fix the machine for the cost of the parts if sent back to their factory. I don't think you can get any better than that. On top of that I can buy SP Smart, their top of the line machine, for about $300 less CDN than the $2,250 CDN cost of the Playmate Volley and get many features it does not have. Yes, our $ is down the toilet again compared to the US dollar. I know the Playmates are built to last but then many have reported they have put 100,000 balls through Silent Partner machines and they are still running without a hitch.

I know that you don't seem to miss the lack of programmability in the Playmate Volley but some report that that is what they like about the other machines. I think I will really appreciate the all-court oscillation that the SP Smart provides. It's hard to miss if you've never had it but then sometimes when you have it 'you don't know what you got 'til it's gone' to quote a lyric from one of Joni Mitchell's songs (she's Canadian you know!).

Aside from programmability, one of the other features I've really had to think about was internal vs external oscillation. That seemed to be a biggie among many people on this forum. I decided that if I was going to get that I'd go for the Spitfire Pro 2 (made by a company another one of our Commonwealth countries - Australia), available for about the same price as the Playmate here. However, I just didn't think that was, for me, an important feature. I am only a 3.0 player and I don't think me knowing where the ball is coming from really that much of an advantage. Maybe once I get a lot better and have mastered all the shots and really feel that internal oscillation would be a huge benefit then I'll sell my SP Smart and buy a machine with this feature, but I think that is a long time coming. For now, when I do use it then being able to have balls served to me using all-court oscillation, programmable drills or match play presets will keep me confused and busy enough. Aside from that, the Spitfire has almost no programmability, hasn't been in the business as long as their competitors and I'd have to deal with an exclusive Canadian retailer for the product, which always seems to have its own issues when the manufacturer is foreign.

My decision might be different if I lived in the US but given I live here I think I will likely buy the Silent Partner Smart and post a review of it after I've used it for a few months.

Thanks again for that in-depth review like no other.

 

[neverstopplaying]

I've owned machines from SP and Playmate. Though they were both top of the line models, the Playmate is pretty much a club machine, and has a much higher price tag. From what I've read, I would expect the Volley to be the same build quality and usability.

Over the course of 7-8 years of use, I had to buy 3 circuit boards for the SP Pro. The service was good and fast, but I still had to go through the pains - it's not that easy to access the inside of the machine. I don't know if the new ones are better. I bought the Playmate used and in 3 summers for use, it has performed flawlessly and looks like its designed to be serviced.

Something that never gets talked about is the realistic quality of the ball launch. The Playmate launches a more realistic ball than the SP. This can only be due to the design and size of the rollers that project the ball, but there is a definite difference between the two. The way the SP spurts out the ball doesn't feel the same on contact as a ball coming from a racquet on the other side of the court.

I can understand your desire to buy local; so if you do I should also note that before trying the Playmate I was very happy with all the years of using the SP. Enjoy our short summer with your new machine!

 

[TorontoTennis]

Thanks for your comments. Nice to hear from someone in Canada. I try to make the season here in Toronto last as long as possible (and are winters are generally nowhere near as harsh as in Montreal). I am going to try to play outdoors from the next Thursday (when it will be 13C here) until sometime in October. That's almost 7 months!

The SP Pro is no longer manufactured and hopefully the current series has a better build quality as you should never go through 3 circuit boards in 7-8 years on any electronic device. That suggests some type of design flaw causing the board the board to be fried repeatedly by current or a poor quality circuit board build. However, if it was a version with AC-DC capability and plugged in, it's possible line voltage surges could have caused that. I am going to talk to Steve at Silent Partner and ask him if there was an unusually high defective rate with the SP Pro's. I haven't noticed any one else having your experience with the quality of their machines. BTW, the circuit board part currently costs $150, the remote $150 and the motors $50 each.

That aside, I am surprised (and fascinated) at your comment that the ball launch on your SP Pro was not as realistic as on the Playmate. I have not heard this criticism of any other ball machine that uses the roller wheel method of propulsion, which both the SP series and Playmate do. What determines how a tennis ball feels on your racquet is, as far as I know, the condition and brand of the ball, elevation and angle (both horizontal and vertical) of propulsion, any topspin or backspin applied and the speed of the ball (and any wind but that has nothing to do with the machine). Have I missed anything?

All of these parameters are user configurable on both the SP Pro and the SP Smart (and many of SP's lower end models). You did not mention which particular model and version of the Playmate you found had a more realistic ball throw but given it was a top end model it no doubt had similar settings. Is there yet another configurable parameter on the Playmate, which might be the reason a ball thrown from that machine feels more realistic? I am dumbfounded what it could be. And, if no other parameter then is there some difference in design in the Playmate that could possibly make the ball feel more realistic even though it also uses the roller method of propulsion? I mean, the ball sure doesn't know what machine it is being propelled from, lol. It can only act according to the forces that are applied as a result of the parameters that are set.

I'd be interested in what you or anyone else thinks or if anyone else has found balls propelled from machines other than the Playmate, and the SP Series in particular, do not feel realistic. I'd really be interested in hearing from AndI's thoughts on this if he is still around.

 

[neverstopplaying]

I knew my comment on the realistic ball feel would throw a curve in a ball machine discussion. I don't believe the difference could be related to settings but the difference in motors, wheel design and the internal launch path of the machines.

But the SP is a $2k machine and the Playmate that I have is a $6k machine new. However Playmate reps told me that both mine and the Volley would launch the same ball.

I don't want to stretch out the comment too much as it's been three years. I was actually surprised when I got the Playmate that it felt much more like playing against a real racquet. I'd be curious if others have played with Playmate vs. different brands and noticed this (or not).

Off the the courts now (indoor of course) ...

 

[TorontoTennis]

A motor and wheels provide a certain propulsion, spin, internal launch path/throw angle, throw height etc, or it doesn't. 50mph is the same no matter what motor is providing that speed. Same with angle. 30 degrees from the horizontal or vertical is just that. The machine can only throw the ball in a straight line at the very moment it ejects from the machine and then other parameters take over that dictate its trajectory such as velocity, speed, spin, etc. Spin is the same. Either it is a certain degree of topspin or backspin or it is not. Btw I should mention that there is also sidespin but few machines do it but the only one in the Playmate series that does is 'The Slam' and that could make a difference but that's priced way more than your $6K machine. It could also be that the balls are being ejected at slightly different heights because the point at which it leaves the wheel is higher or lower on one machine than the other, but I can't think of anything else that could lend credence to what you are claiming.

So, aside from the two possibilities I have mentioned, with all due respect I have to say that what you are claiming does not make sense from a physics point of view. I am an engineer. Once the ball ejects from the machine with certain parameters that's all that matters and that is what will affect how it feels on your racquet. A different wheel is not going to provide the 50mph in a different way or provide the same degree of spin differently (unless it is somehow providing some sidespin in addition even though it is not supposed to) and so on. Of course if the playmate is set to provide a shot at a certain angle, velocity, spin etc and the SP is too but the latter is actually calibrated differently and so is a bit off from the parameters expected then of course the ball will feel different. But that has nothing to do with the machine itself but with the settings and no two machines with exactly the same settings are going to provide the same ball parameters to the ball when ejected. But, that can be adjusted for and if you then do that and ensure that even with settings that are slightly different the ball is being ejected with the same parameters (by testing the actual parameters of the ball) then it is simply impossible for the ball to feel different.

Also, I would venture to say that you have not tested both machines exactly side by side at the very same time with the same brand of new balls tested to eject with the same actual speed, height, spin, etc and so your observation is heavily biased towards what you are currently using. How can you accurately compare the feel of a ball on your racquet at different settings on different machines used at different times? Impossible. On top of that there is a big bias in you knowing the machine you just happen to favour the 'racquet feel' of when a ball is thrown just happens to be $6,000 or more than 3 times the cost of the $2,000 machine. That is far from a blind test which is the only test that can be relied upon.

You are quite alone in claiming there is a different racquet feel. I've read pretty well every ball machine thread on here and on other sites and this is the first time your claim has ever come up and it seems to me it is for good reason.