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View Full Version : Is "plow-through" only related to the weight of the frame?


Murrayalmagrofan
03-13-2012, 07:57 AM
Okay, I have two different racquets with similar swingweights and balance which play completely differently when hitting my 1HBH.

Racquet #1: My Head Microgel Radical Pro racquets are weighted to 12.1oz and are 6 pts head light. The headsize is 100sq in, and the stiffness/flex rating = 64.

Racquet #2: My Slazenger Pro Braided racquets are weighted to 11.8oz, and are 5 pts head light. The head size is 95sq in, and the stiffness/flex rating = 73.

A comparison from TWU is below:

http://farm8.staticflickr.com/7191/6833298940_7329b7960c_b.jpg

Both racquets have a similar open string pattern (Head is 16/19, Slaz is 16/18 ) but when hitting my 1HBH, the Slazenger has noticeably better plow-through. The twistweight of the Head is actually much better than the Slaz, so this has left me completely puzzled???

Is the difference that I'm noticing related to the smaller headsize of the Slazenger vs Head?

eleventeenth street
03-13-2012, 08:49 AM
i'm not an expert on this stuff but stiffness probably plays a part, as well as the distribution of weight on each frame, particularly in the head of the racquet, one frame being 100 sq in, and the other being only 95 sq in

BC1
03-13-2012, 10:10 AM
I don't believe twistweight is a factor in plow through, unless you are hitting on the edge of the stringbed. I do know as far as twistweight is concerned, larger head sizes will typically have a higher twistweight, and so will more HH racquets.

And I would agree with 11th street comments: weight, weight dist, and smaller head size should increase plow

Murrayalmagrofan
03-13-2012, 10:32 AM
And I would agree with 11th street comments: weight, weight dist, and smaller head size should increase plow
That makes good sense. Great input folks.

Seat of the pants feel is just insanely different between these two racquets. The Microgel feels solid, but the Slazenger is just other-worldly. I can handle so much more pace with the Slaz and generate my own pace so much easier. I'm starting to see why Federer and Dimitrov play with a 90sq in head size.

BC1
03-13-2012, 10:45 AM
This may also help:
http://twu.tennis-warehouse.com/cgi-bin/plowthrough.cgi

From TW: More weight will increase Plowthrough and lower racquet speed lost (i.e., less shock). Adding racquet speed increases Plowthrough but also increases speed lost (i.e., more shock)

Also from TW:
A heavier frame = more power.
A heavier frame = less vibration.
A heavier frame = larger sweetspot.
A stiffer frame = more power.
A stiffer frame = larger sweetspot.
A stiffer frame transmits more of the shock load to the arm than a more flexible frame.
A stiffer frame provides a more uniform ball response across the entire string plane.
A larger frame = more power.
A larger frame = resistant to twisting.
A larger frame = larger sweetspot.
A longer frame = more velocity and therefore more power.
A longer frame = more spin due to increased velocity.

(more information then you asked for, but relevant to topic)

Murrayalmagrofan
03-13-2012, 11:32 AM
^ Good info.

So more weight will increase plowthrough, but I wouldn't be surprised if my racquet head speed has increased with the Slaz frame (due to the lighter weight, slightly lower swingweight and smaller headsize).

Power Player
03-13-2012, 11:45 AM
Stiffness has to play a role. I have heavy Wilson 6.1s and light Pure Drive +s and the Pure Drives plow the ball just as well with just 3-5 grams of lead at 12.

Murrayalmagrofan
03-13-2012, 11:49 AM
Thinking about this some more, what tennis players call "plow-through" seems to be related to the force the racquet exerts on the ball at impact.

From middle school physics:

Force = Mass x Acceleration

So if you increase mass, while acceleration stays the same, force will increase. However, if mass decreases slightly, but acceleration increases significantly, the force at impact will be greater.

I imagine it's easier to "accelerate" a racquet with 95sq in headsize vs one with a 100sq in headsize. So the improved "plow-through" I'm experiencing is probably related the higher racquet head speed I'm generating.

Murrayalmagrofan
03-13-2012, 12:02 PM
Stiffness has to play a role. I have heavy Wilson 6.1s and light Pure Drive +s and the Pure Drives plow the ball just as well with just 3-5 grams of lead at 12.
This makes perfect sense.

The "floppier" a frame, the more energy that would be lost in frame flex at impact. I can see stiffer frames being more efficient at imparting force to a ball.

fuzz nation
03-13-2012, 01:07 PM
I imagine it's easier to "accelerate" a racquet with 95sq in headsize vs one with a 100sq in headsize. So the improved "plow-through" I'm experiencing is probably related the higher racquet head speed I'm generating.

A frame with a slightly larger hoop size really shouldn't swing slower than the smaller one with about the same weight and balance, at least without head covers on them to catch the air. Sounds to me like you could simply be more comfortable swinging the Slazenger and if you can catch the ball on the sweet-spot with that one more consistently, I'll bet that feels like you're more effectively "plowing" the ball, too. Even a feather-weight of a racquet can feel as though it's delivering some degree of plow-through when the ball finds the heart of the string bed with a good swing.

I've enjoyed racquets with some extra pop that seemed to result more from their stiffness than their heft, but the frames that I can potentially make the most power with in my game are also the heaviest racquets in my collection. When I'm playing well and swinging with good timing, my heavier frames can let me absolutely clobber the ball beyond what I can do with some lighter alternatives.

My one-handed backhand seems to shine with a heavier frame, too. That stability and "plow-through" seem to almost let the racquet propel itself through the ball, just as long as I get the swing going early enough for a full stroke.

Now my old ProStaff 6.1 Classics are both rather heavy and pretty stiff. Those frames give me what feels like really good plow-through when I hit more compact shots including blocked returns of serve and volleys. A heavy alternative with a lot more flex will be stable, but not give me that same pop that the stiffer 6.1's dish out. That less lively response would feel like less plow-through for me, even though that soft frame is stable at contact.

I guess that a sensation of good plow-through depends on how I'm hitting the ball. It's probably one of those confidence inspiring feelings that's a little different for everyone.

Povl Carstensen
03-13-2012, 02:38 PM
I would say string tension affects the feel of plowthrough.

corners
03-13-2012, 08:55 PM
The power potential maps you are looking at show a racquet's intrinsic power, or in physics terms, the apparent coefficient of restitution - basically, the percentage of ball + swing speed going into the shot that comes out as your shot speed. Some racquets lose less energy than others during the collision with the ball - are more "powerful" - and that's what the power potential stat shows. Power potential is proportional to swingweight, with twistweight, stiffness, string pattern, string tension also contributing, but to a much lesser degree than swingweight.

But plowthrough is something different, although it is related to power potential because it also depends on swingweight and twistweight, but not on stiffness, string pattern or string tension. Plowthrough, as defined by TW University (this is a good definition, not necessarily the definition):

The percentage of racquet velocity at the impact location remaining after impact. The lower the number, the more velocity is lost, which means the racquet head (and your arm) experiences a larger deceleration during the 5ms of impact. The higher the number, the more the racquet "plows through" the ball without slowing down as much. A negative number means the racquet location is for a brief instant actually going backwards (due to twist, recoil, rotation), not just going slower!

The above is taken from the Plowthrough tool in the leftmost dropdown menu on the TW University homepage. Plowthrough is pretty much dependent on swingweight and twistweight, which are both measures of how much of the racquet's mass is distributed to the head of the racquet. Static weight does not play much of a role at all. TW University's Customization Worksheet (http://twu.tennis-warehouse.com/learning_center/customizationReverse.php) shows Plowthrough at the center of the stringbed and at 3/9 o'clock before and after adding lead wherever you want to the frame. If you play around with this tool, you can see that adding mass at 12 o'clock raises swingweight, power potential and plowthrough the most, gram per gram, and that adding mass to the handle does virtually nothing to improve any of those three quantities.

So why does everyone say that a heavy racquet has more plowthrough? For two reasons: 1) In the old days, a heavy racquet had high swingweight and light racquets had low swingweight, so heavy racquets were known to have good plowthrough and light ones poor plowthrough. But this is not necessarily the case now, when 11 ounce frames with 330+ swingweight are more common than 12.5 ounce frames with 330+ swingweight. Those two racquets both have the same amount of mass in the head and will both lose about the same amount of speed when colliding with the ball during and identical shot (in other words they have equivalent plowthrough), so what was once true is now more of an old assumption held by players that grew up with heavy racquets and still prefer them.

2) Weight in the handle improves recoil weight, which reduces shock. Another paragraph from TW University's Plowthrough page:

More weight will increase Plowthrough and lower racquet speed lost (i.e., less shock). Adding racquet speed increases Plowthrough but also increases speed lost (i.e., more shock)

Weight in the handle reduces shock by resisting the recoil of the handle on impact. This is not quite the same thing as plowthrough, but many players feel that it is the same because sticks with high plowthrough and high recoil weight transmit the least shock to the hand, giving the feeling that you are bullying the ball instead of the other way around. Racquets with high swingweight, and lots of mass in the handle (headlight balance in other words), are extolled by advanced players as being the the most arm-friendly and ball-unfriendly because they blow through the ball and transmit very little shock to the player's hand and arm.

But low shock is not the same as plowthrough, even though it can feel similar. An example: natural gut strings dramatically reduce shock compared to stiffer strings, but using natural gut is not normally associated with improved plowthrough.

Note: everything written above and much more can be learned by reading the articles and playing around with the tools at Tennis Warehouse University: http://twu.tennis-warehouse.com/learning_center/index.php

Murrayalmagrofan
03-14-2012, 05:13 AM
Corners, excellent post! That was a very insightful response, and it looks like I have some reading to do at TWU.

Thanks again!

BC1
03-14-2012, 05:22 AM
^^^^ Corners, agreed - great stuff! Thanks

sp1derman
03-14-2012, 05:49 AM
Nice post corners!

Power Player
03-14-2012, 07:33 AM
I 4th this..I agree with corners.

corners
03-14-2012, 12:00 PM
Thanks guys.

rst
04-14-2013, 01:13 AM
I would say string tension affects the feel of plowthrough.


wow. string tension affecting feel.