Showing posts with label Vokyl. Show all posts
Showing posts with label Vokyl. Show all posts

Sunday, December 9, 2012

Measuring Swingweight

What is Swingweight and why is it important measure of a tennis racquet performance ?

As per Tennis Warehouse University (TWU)

Much of a tennis hit can be seen as a battle between the player and the ball to move the racquet in a circle. Swingweight is the resistance to movement in a circle. Circular motion (as in most stages of a tennis swing) occurs around a center or rotation, let's say the butt end of the handle. When you apply equal forces to the handles of two racquets with different swingweights, the racquet with the higher swingweight will accelerate less and rotate less quickly around the center of the circle. The lower swingweight racquet will accelerate more quickly. In other words, higher swingweight means less maneuverability, and lower swingweight means more.

But the ball applies a force to the racquet also. And the same principle applies. The lower the swingweight, the more easily the the ball will move the racquet, and the higher the swingweight, the less easily the ball will change the motion of the racquet.

So the tradeoff becomes this: lower swingweight results in greater racquet acceleration and final swing speed, but more shock (due both to more racquet deceleration by the ball and higher impact force due to greater speed). Higher swingweight results in slower racquet acceleration and final swing speed but less shock due to less deceleration due to the ball pushing the racquet in an opposite circular rotation.
Power is influenced also. With a lower swingweight, the power must be generated more from swing speed. With a higher swingweight, more of the power comes from the racquet itself.

The Vokyl C10Pro 2012 which I received a week ago arrived minus 13g off its stated unstrung weight of 330g ie weighing in at 317g.



Strung with Black Widow 18g @ 60lb(actual : 50lbs), the strung weight was only 331g as compared with the stated average of 346g by TW. With the 3g Vokyl damper, the weight as shown on my digital weighing machine is 334g.


I added 13g at 6.75inch above the butt cap and plus the 3g Vokyl Damper, the strung weight is now 346g.
The stated average SW as per TW is 323g (comparison tool shows 331g), I really wondered what is exactly the SW of the leaded up stick which had been playing well (except for kick serves and overheads).

So I tried the SW measurement method as on  http://twu.tennis-warehouse.com/learning_center/swingweight_calc.php  and the results are as follows :




I took the average of 4 readings (13.88,13.93,13.83,13.85) and plug it into the SW calculation tool and the SW = 335g/cm2 which is much higher than the TW average SW of 323. The final specs are as follows :-


Wednesday, December 5, 2012

Hitting with Vokyl C10Pro 2012

Finally... I managed to hit with this highly recommended stick by Chris Edwards, one of the senior TennisWarehouse Play tester. Read his review here.  BTW, there were also quite a few supporters of Vokyl sticks on the Tennis Malaysia and Malaysia Tennis Lovers facebook groups.


Finally ordered and discovered that the Black Friday Sale of USD75.00 was no longer valid and the price increased to USD 159.99 and guess what, it was further increased to USD169.99 the very next day. Coincidentally, I was at the PSC and read in the May 2012 issue of the Tennis Magazine that the MRSP was actually UD 190.00 !

Received the stock on Monday and noted that the unstrung weight should be 330g and balance at 310mm. I took out my trusty digital weighing machine and was shocked that the unstrung weight was only 317g. Wow, a 13g difference... I had expected a +/- 1g difference as experienced with my Bio 100, 200L, 200 (2) and 300. Posted this at the TW forum

On receiving my Dunlop Black Widow 18g string, I had it strung yesterday and the final specs are :-
Strung Weight : 331g ( as compared to the advertised 346g)
Balance : 9.76pt HL (as compared to the advertised 8pt HL)

See TW forum post from another new owner

Posted a question to Chris Edwards on the TW Forum to seek advice on how to lead up to the advertised specs.

Started as usual with serves. Flat and Slice serves were nice and crisp but had some issues getting my kick serves to bounce higher than shoulder height. Managed to get my kick serve back but had to realy get under the ball :-)

BH volleys was very solid probably due to its high Twistweight of 14.16.

FH came with lots of spin and was able to easily hot with depth ie 1-2ft from baseline.

Backhand topspin was also easy to hot with depth and BH Slices was hit pretty crisp and low.

On the flip-side static overheads were not so crisp.