Friction In Practice: A Tale of Two Hybrids

[TimothyO]

My standard setup for a few months has been VS mains and Xcel 17 crosses at around 50-52 pounds. This was based on TW's friction research showing VS Touch-based hybrids showing low static and sliding friction and Xcel's relatively low static friction, at least for a multi (also tried Recoil but disliked it).

I still recall the first time I tried VS + Xcel. Very comfy and excellent access to spin.

Over the last few days I've had the opportunity to hit with two other VS-based hybrids using the new EXO3 Tour 100 16x18. I've had my EXO3 strung twice based on TW's sliding friction research and the results have been interesting! While it appears both static and sliding friction are important for spin potential other string characteristics clearly enhance or degrade a given string bed's quality regardless of spin potential. However, the following is simply anecdotal (but real world) evidence from one middle aged tennis noob (but one who is a fairly observant geek). So take it with a bucket-o-salt.

HYBRID A
Mains: VS 16 @ 50#
Cross: Hurricane Feel 16 @ 47#
Amazingly easy access to spin (I could even hit "curve balls") but VERY low power, at least for this tennis noob. Stronger, more athletic players could generate more power, but when hitting with lots of spin the ball floated and then only rocketed AFTER hitting the ground. In any case, from a purely spin-potential perspective this is an amazing hybrid. BUT...

Hurricane Feel 16 has the lowest sliding friction value and a very low sliding friction value but a very high stiffness rating in the high 200s. More importantly, after only four hours or so of hitting with this hybrid the string bed exhibited extreme notching and the VS was on the verge of breaking. Not a durable setup to say the least.

HYBRID B
Mains: VS 16 @ 51#
Cross: XR3 17 @ 49#
So, after noticing Hybrid A's low power and extreme notching, this morning I had the EXO3 restrung with XR3 17. Power was perfect for this noob and spin potential was still good. Not nearly as extreme as Hybrid A, but somewhat better than average.

However, as the session wore on, the racquet felt board-like in spite of XR3's low-ish stiffness of roughly 170-180. After a couple of hours I had to switch to my PB10 Mid for relief! Heck, the Hurricane Feel poly felt more comfy!

Then tonight I took a look at the EXO3's XR3 strings and WOW!!! What a mess!!! I never had "string movement" problems with Xcel as in strings moving and then not moving back into place. The EXO3's sweet spot looked like one of those op-art illusions of a grid distorted to resemble a sphere. Every impact point was recorded for posterity in the string bed.

Clearly the XR3 was moving around and its high static friction was preventing it from moving back into place.

THE NUMBERS
So, let's look at the static and sliding friction numbers.

Hurricane Feel 16: Static .089 / Sliding .040

Xcel: Static .120 / Sliding Unknown

XR3 17: Static .159 / Sliding .047

While this is based on the anecdotal evidence gathered by a tennis noob, the results might be interesting, at least for other tennis noobs and fellow geeks!

Given the general patter of relationships between static and sliding friction it's quite likely Xcel's sliding friction falls between Feel and XR3.

It seems then that one might need to consider BOTH static and sliding friction when it comes to overall performance AND stiffness relative to player strength and skill when evaluating a string bed's spin potential.

For this middle-aged noob the VS/Feel hybrid generated insane amounts of spin but lacked the pace needed to be a "keeper". Durability was also an issue and would probably be a BIGGER issue for more athletic hard hitters.

The XR3 generated decent spin and power initially but "non-recovering" string movement seemed to quickly degrade the string bed's performance and comfort.

Meanwhile, the spin-friendly VS + Xcel hybrid in my PB10 Mid and London continue to do outstanding work after many hours of play and with almost no noticeable "non-recoverable" string movement, and certainly no notching.

CONCLUSION:
Static friction appears to impose a limit on a string bed's durability with respect to consistent support for spin potential over time. If too high the SB may become less spin-friendly regardless of a low sliding friction value due to a high static friction value which prevents strings from returning to a "neutral" position.

And while exhibiting outstanding spin potential, hybrids combing stiff polyester and comparatively soft gut may suffer from extremely limited life expectancies due to notching and breakage. For less athletic players polys may also limit power potential thus negating any spin advantage.

Therefore, at least for fellow noobs, there may exist a sweet spot for a spin-friendly string bed based on low static and sliding friction. Spin potential would have to be high enough to tame the power of a less stiff SB. At the same time, that less stiff SB would allow a duffer to hit some pretty heavy balls while accessing the SB's spin potential without fear of over-hitting.

For durability purposes, something important to weekend warriors, the relative stiffness and material qualities between mains and crosses should be such that neither degrades the other's performance through movement across one another.

 

[JackB1]

Interesting stuff! I still can't believe you are able to use nat gut mains w/ multi crosses with the London! Are you able to swing away and keep the ball from sailing? You don't get any of that trampoline effect with that setup? Especially at that low tension? What type of ball do u hit? Is it a slower loopy shot, lots of topspin or mode flat? I wonder if the nat gut in the mains gives u more topspin than a multi in the mains would and thus more control? I have never tried nat gut in my London for fear balls would be launching on me, like they did with my multi/copoly setup. It might be worth a try

 

[TimothyO]

Interesting stuff! I still can't believe you are able to use nat gut mains w/ multi crosses with the London! Are you able to swing away and keep the ball from sailing? You don't get any of that trampoline effect with that setup? Especially at that low tension? What type of ball do u hit? Is it a slower loopy shot, lots of topspin or mode flat? I wonder if the nat gut in the mains gives u more topspin than a multi in the mains would and thus more control? I have never tried nat gut in my London for fear balls would be launching on me, like they did with my multi/copoly setup. It might be worth a try

As far as shots go, all of the above!

I've found the VS + Xcel hybrid to be extremely versatile, at least for this middle aged noob!

With the London and PB10 Mid it generates lots of spin when swinging hard-ish to keep the ball in play. When hitting flat and slower the power remains controllable. Neither racquet is great at volleys but this low tension setup provides ok pop.

Besides, both the PB10 Mid and London are fairly soft which mitigates this hybrid's power (which is why I'm so enamored with the EXO3...big spin-friendly 16x18 hoop in a soft, low power frame). But the key to hitting hard is spin. The London's incredibly feel makes that easier than many frames.

All that being said, if i don't pay attention to what I'm doing, yes, I can launch balls. But if I look the ball into the SB and focus on my swing arc then there's no worry about launching balls.

I just dropped of my EXO3 Tour to be strung with 50# VS 16 Mains and 48# FXP Power 16 Crosses. FXP is stiffer than Xcel and has a lower static friction value, so I'm very curious as to how the hybrid will perform in a 100 sq in 16x18, low stiffness frame. Probably won't get to hit this week, hopefully next weekend!

Being I noob I feel like I'm homing in on a noob-friendly, control oriented "players" configuration.

- Very soft Frame for comfort and lower inherent power

- Mid-plus hoop with 16 mains and low friction hybrid string for easy access to spin

- Low friction gut mains / multi crosses to provide enough spin-tamable power without having to be an athlete

 

[JackB1]

Thanks for the response Tim. When are we going to have a hit together?

 

[TimothyO]

Thanks for the response Tim. When are we going to have a hit together?

Soon! In the coming weeks we have the completion of the ALTA winter season, the Super Bowl (woohoo!), my son's scout camping trip, my other son's music fest (plays the sax), fencing stuff, and a major honey-do.

Weather was certainly beautiful this weekend (but didn't get to hit today! Pinewood Derby).

Perhaps sometime in the next week or two. You can show this noob how to serve properly. I'm absolutely TERRIBLE. Sometimes I can nail it but mostly I'm just consistently inconsistent. Have had a couple of lessons, wasn't impressed with the pro. Looking for a new one.

 

[g4driver]

HYBRID A
Mains: VS 16 @ 50#
Cross: Hurricane Feel 16 @ 47#
Amazingly easy access to spin (I could even hit "curve balls") but VERY low power, at least for this tennis noob. Stronger, more athletic players could generate more power, but when hitting with lots of spin the ball floated and then only rocketed AFTER hitting the ground. In any case, from a purely spin-potential perspective this is an amazing hybrid. BUT...

Hurricane Feel 16 has the lowest sliding friction value and a very low sliding friction value but a very high stiffness rating in the high 200s. More importantly, after only four hours or so of hitting with this hybrid the string bed exhibited extreme notching and the VS was on the verge of breaking. Not a durable setup to say the least.

TimothyO,

Read my thoughts on VS Touch Mains / Hurricane Feel 17g Crosses versus Hurricane Feel 17g mains/ X-One Bi-Phase 16g Crosses

http://tt.tennis-warehouse.com/showthread.php?t=357777

I have since lowered my tension on the Hurricane Feel17g Mains to 57lb / X-One 16g to 54 lbs. I love this setup. The X-One always breaks first, around 15-18 hours.

Hurricane Feel might be listed as stiffer than some polys, but to me it feels much softer than WC Scorpion (which I thought felt much stiffer) compared in an exact setup of my Hurricane Feel 17g/ X-One Bi-phase 16g on the same frames, Wilson BLX Pro Opens.

I have no problem at all generating power with this setup, especially on forehands, volleys, and overheads. The only lack of power I notice from either the VS Touch/ Hurricane Feel or Hurricane Feel / X-One setup is on my serve. That is due to the two titanium screws in my lower back, which limit my ability to hit a flat serve.

IMO, after nearly five months of hitting with Hurricane Feel, I think it is the most underrated poly I've read about. I haven't tried Blue Gear Ultra, but I am getting the results I want with my current setup. I'm opened minded to try new setups with my third Pro Open, but for me Hurricane Feel 17g/ X-One Biphase 16g works. I string my own frames, but I don't see the need to switch to a 17g multi-cross if I can get the control, power and spin from a 16g that gives me a few more hours before popping.

 

[danno123]

It's interesting that, from your write-up, it appears you got more notching of the mains from a 16 gauge low-friction cross than from a 17 gauge high friction cross. I would think that a thicker gauge and less friction would result in less notching. I suppose the fact that the mains never moved with the high friction crosses might account for it.

 

[g4driver]

For this middle-aged noob the VS/Feel hybrid generated insane amounts of spin but lacked the pace needed to be a "keeper". Durability was also an issue and would probably be a BIGGER issue for more athletic hard hitters.

The BB London and Wilson Pro Open are almost identical in swingweight, static weight and both 4pts HL, but you were using a Prince EXO Tour 100 16x18 for this demo. I am guessing the Pro Open I use has quite a bit more power than your Prince EXO Tour 100, hence I found plenty of power in the VS Touch / Hurricane Feel setup.

I even strung my frames at 62 lbs each, giving me control over power. I've since lowered the strings to 57 / 54, but even at 62 lbs I got over 20 hours out the frame I strung before cutting them out. The other frame popped quickly, but I think I must have had some Har-Tru Clay near the grommet which likely cut the VS Touch. The heavy topspin finished it off. The VS didn't break in the sweetspot, but rather near the top of the hoop.

Jack,

Did you ever try the NRG2/ Hurricane Feel? Don't read the specs on Hurricane Feel. It plays much softer than WC Scorpion IMO.

 

[TimothyO]

It's interesting that, from your write-up, it appears you got more notching of the mains from a 16 gauge low-friction cross than from a 17 gauge high friction cross. I would think that a thicker gauge and less friction would result in less notching. I suppose the fact that the mains never moved with the high friction crosses might account for it.

Perhaps it was the relative stiffness? I don't know. But it was so extreme that when moving the strings by hand there was a very loud and distinct "clicking". It felt like snapping lego bricks together! I was also deliberately hitting with as much top spin as possible. Could that speed and angle contribute?

 

[TimothyO]

The BB London and Wilson Pro Open are almost identical in swingweight, static weight and both 4pts HL, but you were using a Prince EXO Tour 100 16x18 for this demo. I am guessing the Pro Open I use has quite a bit more power than your Prince EXO Tour 100, hence I found plenty of power in the VS Touch / Hurricane Feel setup.

Yup, this EXO3 is only 52 or 53 stiffness. Plus, while I love playing 3+ hours at the height of an Atlanta summer day (my wife thinks I'm crazy), I'm no athlete. I just got the feeling that my high spin shots with this configuration were "floating" in a weird way. Almost certainly a user problem rather than hardware problem!

 

[alidisperanza]

Nice findings + Interesting thread!

 

[JackB1]

Soon! In the coming weeks we have the completion of the ALTA winter season, the Super Bowl (woohoo!), my son's scout camping trip, my other son's music fest (plays the sax), fencing stuff, and a major honey-do.

Weather was certainly beautiful this weekend (but didn't get to hit today! Pinewood Derby).

Perhaps sometime in the next week or two. You can show this noob how to serve properly. I'm absolutely TERRIBLE. Sometimes I can nail it but mostly I'm just consistently inconsistent. Have had a couple of lessons, wasn't impressed with the pro. Looking for a new one.

Sounds good. Just email me through my profile when u want to play some.
I bet I can help your serve. I am actually a very good teacher, having taken many lessons myself and researched everything tennis related humanely possible. Yes the weather was great. I played Sat and Sun and didn't want to stop

 

[JackB1]

Jack,

Did you ever try the NRG2/ Hurricane Feel? Don't read the specs on Hurricane Feel. It plays much softer than WC Scorpion IMO.

No. I may try it though. How is the power level? I don't want a powerful poly. I need more control with the London.

 

[g4driver]

Jack,

You just have to try it. It's not stiff to me, good spin, great control and IMO plenty of power.

SC Scorpion feel much stiffer to me. I have two 4.0s and one 4.5 using a Hurricane Feel 17g / Prince Topspin 16 g setup, but that's because they break strings too fast. The Prince Topspin gets them roughly 15-20 hours. The break NRG2 and X-One in about half that time.

 

[g4driver]

And If you want more control, string your frames at the upper limit. You'll get more control, less power.

I had TE for years, and recently had it with some Prince Pro Whites. My TE has gone away. Since it's cold out, I've dropped my tension to 57 / 54, but plan to increase the tension again in warmer months, back up to something like 60 / 57.

 

[g4driver]

Yup, this EXO3 is only 52 or 53 stiffness. Plus, while I love playing 3+ hours at the height of an Atlanta summer day (my wife thinks I'm crazy), I'm no athlete. I just got the feeling that my high spin shots with this configuration were "floating" in a weird way. Almost certainly a user problem rather than hardware problem!

To get more topspin, "chin the ball", meaning come underneath it to strike it on it's "chin" if the ball were a face, then follow through, finish the swing and up and over your opposite shoulder.

I'm a flat hitter by design, but I've learned to hit heavy topspin, by changing my swing. I still hit flat, but save those shots for slower players, or for putting the ball away against faster guys when I can get them in a corner or moving against the direction I go. (Meaning a guy is running from the deuce court back to the middle along the baseline, and I simply flatten out the ball and hit to the deuce corner behind him.)