tennis racket stringing: advanced tips + how to use a single clamp machine
Channel: Frederic Sarge
Date: 10/04/2015

In this video, I demonstrate a full string job (two piece) on a Babolat VS 2001 electronic stringing machine (from circa 1990).
The linear tensionning system on this machine is great, super precise and dependable, and the central/fixed clamp is massive, so it is rock stable. However it's only a *single* central clamp, so in order to achieve fast, professional quality results with it, you have to learn a few tricks.
As a reward, you'll obtain extremely accurate results, usually quite a bit better than what you'd obtain with two-clamp machines that have much shallower clamps.

Please enable the subtitles in the video if you want to see the explanations, they are not spoken !

First, you need some good starting clamps and/or floating clamp to block the string on one side while you proceed on the other side.
The more you have, the easier it will be.

One starting clamp is usually enough for poly strings. However, I prefer to use two starting clamps in a row to really ensure there is no slippage with more elastic strings (gut, synth gut, soft multifilaments...). Especially for the first two central strings.
I further use when possible (not every place on the frame can accomodate it), a good quality floating clamp to block the string against the frame because it is so much more secure and comfortable.

In order to switch side, just remember to:
1) apply tension to the current string
2) while tensioning, move the central fixed clamp to the string that 
     is currently blocked by a floating/starting clamp
3) remove that floating/starting clamp and place it on the string that 
     is being tensioned, on the outside of the frame
4) release tension

Second, if you are really serious about stringing, you just can't apply the same tension to every string, because the slight bending of the frame that occurs when you string several strings in a row on one side before switching to the other side will ruin the evenness of tension.

So you have to adjust tension in some places to compensate.
This slows downs the weaving of the mains by a few minutes, but the resulting quality gain is very much worth it.

Here are the maps of tension adjustment in kilograms that I use for 16 mains.

Rackets with the first two strings' loop located at the head :
-------------------------------------------------------------------------------

8B === +4.5 (knot)
7B === +0
----- (second side switch here)
6B === +0
5B === +0.5
4B === -0.5
3B === -0.5
2B === -1.5
1B === +0
----- (begin here : pull first two mains together at +4 Kg)
1A === +4
2A === +2.5
3A === +0.5
4A === +0.5
----- (first side switch here)
5A === -0.5
6A === +0
7A === +0
8A === +4.5 (knot)

You start at 'begin here', pulling both 1A/B strings, continue stringing up to string '4A', block, switch side, continue from 1B to 6B, block, finish A side, tie knot, finish B side, tie knot.

Rackets with the first two strings' loop located at the throat :
-------------------------------------------------------------------------------

8B === +4.5 (knot)
----- (second side switch here)
7B === +0
6B === +0
5B === +0.5
4B === +0.5
3B === -1
2B === -1
1B === -1
------------ (begin here: pull first 2 mains together at +4Kg)
1A === +4
2A === +2
3A === +2
----- (first side switch here)
4A === -0.5
5A === -0.5
6A === +0
7A === +0
8A === +4.5 (knot)

You start at 'begin here', pulling both '1' strings, continue stringing up to string '3A', block, switch side, continue from 1B to 7B, block, finish A side, tie knot, finish B side, tie knot.

I'll also demonstrate several rather nerdy techniques of mine, such as ear-driven evening of tension (see at 10:25), or on-the-go prestretching of the mains (you proceed to weave one string ahead while the tensioner is pulling, so that the string has time to stretch for several seconds. This gives fantastic tension maintenance.)