String "Timing"

Being a former high string tension user myself, I now advise others to string as low as they can still control the ball with.

By high-tension in today's viewpoint, I mean 60 lbs and above with full poly or most poly hybrids.

Dropping tension has more advantages than disadvantages. While not everyone would be able to adapt, most should find no big problems, with only slight changes in their swings. 

With full permission from this chap I have been speaking with, I reproduced below what I thought was an interesting myth regarding tension and accuracy. Let's call him "K".

For as long as I can remember, K has been stringing his 16x19 stringbed with full 16g poly at 68 lbs. K is a strong guy. He hits hard and snaps thinner poly strings frequently.

Like many hard hitters, K prefers his stringbed as dead and as low-powered as possible. He believed in minimizing all power variables and allowing himself to be the sole power generator. Thus maximizing control and accuracy.

We couldn't find any paper with us, hence we drew on the back of an envelope...

Below is a graph depicting string "Pocketing Depth" vs "Time". Time "0" is when ball impacts stringbed.

"A" is a soft string, like natural gut or multifilament.
"B" is a stiff string, typically poly.
Both "A1" and "B1" show the respective string's rebound after it has lost tension. 

So, when freshly strung, the softer string "A" offers more pocketing than the stiffer "B". As a result, the dwell time, or how long the ball stays on the string, is longer for "A" and shorter for "B" too. This is true even after "B" loses tension to become "B1".

In K's opinion, the shorter the dwell time, the better. 

If you refer to the bottom half of the above drawing, it shows a right-hander hitting a ball with a racket. The contact point is "X", and "Y" is the point where the ball leaves the stringbed. So the time between "X" and "Y" is the dwell time.

K's argument was, since the ideal ball impact location is way in front of our body, a long dwell time would mean the ball leaving the strings too late. By then, the racket face would have rotated inwards. The shot would go left instead of straight.

That was the only complaint K had.

So I did some simplified calculations with him to prove my point:

Average dwell time generally accepted: 5 milliseconds
K's fastest swing speed: 78 miles per hour
5 ms = 5/1000 second = 0.005 second
78 mph = 124.8 km/h = 124800 m/h = 2080 m/min = 34.67 m/s

So, during the duration of the 5 ms dwell time, based on K's swing speed, his racket would have travelled a distance of:

34.67 metres per second  X  0.005 seconds
= 0.17335 metres or 17.335 cm or 6.82 inches

My point is, all K needed to do, was to chase the ball forward with the racket, or even upwards for topspin, after impact.

6.8 inches is slightly less than the diameter of three tennis balls. Perhaps that's why coaches keep barking:

"Hit through the ball"

"Visualize hitting through 3 or 4 tennis balls"

Whether it is a string tension problem, long dwell time problem or swing timing problem, I left it for K to mull over.




     

"Annual Pilgrimage" with Budget Natural Gut

Over Christmas, after the gift exchanges, a friend gave a set of budget natural gut to me. He received it but did not care for it.

I happily accepted it and offered to post my review. 

It was in a transparent plastic bag. No names nor labels. Just a type-written sticker pasted over the sealed bag, saying "Naturel Gut".

The gut looks very smooth and had a translucent glow, something like Klip and Babolat VS. Other than the packaging, it does not look like budget stuff to me.

After clearing most of the backlog of work and stringing requests, I thought maybe it's time for my annual pilgrimage with the ProStaff 6.0 again... (link1)(link2)(link3)...

All the standard steps were strictly adhered to. Things like cleaning clamps, prestretching gut to remove coil memory, checking grommets for sharp edges, etc.

However, the natural gut snapped during tensioning. I had only completed 6 mains when it happened. All at a modest tension of 55 lbs.

Fortunately, the snap point still left me enough gut to fill only the centre mains in the ProStaff 6.0, like in the "Lendl Pattern" (link).

So I filled the outer perimeter with poly first, then started on the mains very very carefully and slowly...

But just when I was tensioning the second last main string, the natural gut snapped again! Somehow, the first snap point triggered a second snap point in the natural gut!!!

Of the three snaps so far, none occurred at the clamps.

Could installing budget natural gut into the ProStaff 6.0 be disrespectful and blasphemous? Was that why the gut kept snapping? Because the ProStaff 6.0 rejected it?

After one hour, two failed attempts, with three snap points, I was beginning to understand why my friend was so "generous" to give me that pack. 

Since I had gone so far, I decided to continue with the remaining half-set in the pack and be done with it. Successful or not!

At last! 

Ended up with so many short pieces of snapped natural gut! 

It played very well, but I doubt I would use these budget stuff again. Really a waste of time!




     

Fishing Line...again...

Over coffee with a friend who reads this blog, he asked when would I be using fishing line again. 

He added lots of very persuasive talk. I knew, of course, that he just wanted to enjoy the incredible feel, bite and spin of fishing line again.

However, some things he said resonated. 

Like, would there have been any improvements in fishing line technology to make it more durable and less likely to snap? 

And, have I tried applying some of my newer stringing techniques to deal with the frequently snapping fishing line?

These questions started me thinking... 

...then my hands and feet just followed...

One major problem I had previously was knot slippage. The fishing line was SO THIN, tying knots became incredibly difficult. 

Pull too tight and it'll snap. Pull with my bare hands and it cut straight into my flesh. Double knots snapped the string too. And those knots that I succeeded, often slipped into the grommet hole and the string lost tension!

So I tried a double knot over the "Dead Man's Knot". It worked beautifully! No slippage. No need to pull too tight. No tension loss. No grommet damage. Perfect!

For prestretch, I used a friend's fishing line reel line winder which he built himself using an electric drill! Something like this. I told him what I was after, left the fishing line with him for a few days and "Voila" it's done! So simple!

I think this was my smoothest and most peaceful fishing line stringjob ever! Success in one attempt! If you do not understand the challenges, just read my past posts on fishing line. To me, this is a big deal!

And the other good news was the thin fishing line did not even notch after the initial 90 minutes!

Yes! It was blissful hitting with it. My partner that day commented not only on the extra spin but accurate placements as well. And I could pull him extra wide on those sidelines serves!

Hmmm... why did I forsake fishing line?!?!




     

Wet Tennis Balls

Someone I string for commented that he could not control the ball in slightly wet weather.

My reply was tennis was meant to be played in dry conditions.

Nevertheless, here's my thoughts on how wet balls affect the strings...

All of the above six balls weighed 59 grams when dry. 

The top three balls were soaked in water for ten minutes before weighing. The bottom three were rolled around on a wet floor.

The average weight of the top three and bottom three was about 73 grams and 68 grams, respectively, with a difference of about 5 grams.

Compared with dry balls, the top and bottom weighed an extra 14 grams and 9 grams respectively.

All these were static measures on a stationary ball. The difference is perceptible but insignificant.

However, once the ball starts moving at high speeds, the additional weight increases its momentum very significantly.

Momentum = Mass x Velocity

Without getting too much into detailed calculations, a simplified version looks like:

Dry Ball Momentum = 59 grams x 50 mph

versus

Wet Ball Momentum = 73 grams x 50 mph

And that's only for the average rally speed in tennis. For serves, the speed often increases to 100 mph, or more. Even for many recreational players.

When tensioning, I often take into account the players' footwork, tempo, racket head speed, string pattern, string gauge, choice of string, etc. And all these are based on DRY conditions.

Can you imagine what would happen, after all the weight measurements were taken, and the appropriate bungee cord attached for that single person, then three jumpers just decided to strap together to jump?

Of course there are other factors, like the wet felt on the ball reducing ball-to-string friction, the wet court affecting bounce, and the fluffed up fur changing trajectory. 

But to me, the huge increase in momentum delivers the biggest impact to the stringbed. Which was why I liked using damp balls to train myself before playing with a heavy hitter last time.

In addition, after the extra stress from playing with wet balls, the stringbed would usually lose too much tension thereafter.