I thought of one other reason why it happened ... This particular racquet, i prestrung it first. And maybe the cross strings were a tad tight
That's correct. You should aim for the original shape. However, there is always some differences between an unstrung and strung frame, no matter how careful you are with the stringing process.
Bazzaman, what modifications did you do to the clamps? Did you simply tighten the bottom nuts or did you cut reshape the contact area of the clamps?
The original clamps were just a plastic/rubber flat base with a flat metal clamp. I made an improvised V clamp for the bottom but still haventchanged the top clamp yet. Just hope the glue is strong enough
Hey Pete, thanks for all the help. There's no written rule about adding 10% tension to the cross, so If my clamps are solid I could reduce it to 0-1 lb on the cross?
My pleasure, Bazzaman! Yes, there are no rules about adding 10% tension to the cross. If you are stringing for recreational use and expect at least two months of string life, then add about 1 lb to the cross. The key is to maintain the shape of the strung frame as close to the unstrung one for as long as possible. What I notice is that overtime the width of the frame increases. This is a very difficult thing to do given so many variables in stringing, from different stringing machines to the type of frames.
At the moment its half V, just gotta figure out what to glue to the otherside. Or i might clamp by 2 half Vs top and bottom but its all temporary for now. I thought about using something similar to thick plastic tubing cut in half Well just for giggles heres my macguyver clamps made with some nylon pads, epoxy and a razor
May I suggest you dismantle all the modifications and instead try a much simpler and yet more effective solution. Revert back to its original state. In place of the half V use a small thin strip of felt, cut to the same shape and size as the clamp support, then glue it with epoxy resin. For the top side of the clamps buy a piece of about 1.5mm to 2mm thick leather skin and cut it into strips of 10mm width. From each strip cut four pieces, each 12mm long. Use these 4 small cut strips of leather now, each measuring 10mm x 12mm with a thickness of about 1.5mm to 2mm, and put them in between the four clamps and the racquet frame. Then tighten the clamps with your hand as tight as you can. Re-tighten them again to ensure there is no slack. Don't worry, the frame will not crack as the four contact points are well cushioned. The reason for the extreme tightness is to prevent slippage. As the 4 leather strips wear off, cut the strip again for replacements. It is a good idea to re-tighten the clamps again after you have finished the mains and before you start the crosses. For higher tensions above 28lbs to 34lbs use a large plier to clamp tighter.
Hi taneepak, thanks for the suggestion... but the main reason why I had to modify it was because the original clamping method was very poor. I already tried repairing the original clamp quite similar to what you suggest, ie hard rubber base , and old PU grip for the top. I might just buy some other stringing machines clamps instead, like the ones Pete linked. Either way, I'm gonna keep using it until it starts slipping. And then I might get someone else to string for me lol
Don't use any pu or hard rubber base. Use a thin felt, similar to those very thin cheapy carpets, on the bottom clamp. On the top clamp, only leather will do as pu will be useless. If done correctly you should be able to string at 30lbs without any distortion (less than 1mm), and that even when stringing the crosses top down at 32lbs. BTW, the type of clamps used on the ST-200 are conceptually better than almost all other types of clamps, but the devil is how to clamp it correctly. This is because its clamping system does not allow for any inward or outward movement whereas other systems allow, i.e. V shape clamps allows inward movement.
OK Tanepak Gotcha, any idea where to get the felt and leather in HK. And how thin should the felt be 3mm? And I should be clamping close to the angled edge of the top clamp? I don't know if you've used this clamp before but the top clamp angles sometimes making it a pain to release
I have two stringing machines, including an Eagnas Easy 3 which has a fixed clamp but I removed that. To all intents and purposes it is now like an ST-200. But I use 5 fying clamps and a starter clamp. So I am very familiar with the clamping system. The top clamp is very critical because it is all metal and a metal angled edge. So you have to use a thin leather to clamp the top with the leather covering the angled edge. If the leather is too thick the clamp will move; if too thin the clamp will puncture the leather. You have to work this out yourself. Leather is ideal as it doesn't generate as much heat. The clamps are easy to release. Just use a large plier to loosen the 4 large bottom knobs initially and then use your fingers. The bottom part of the clamp is not so critical as it has a larger surface area and any 1mm to 2mm thick felt will do. The only function of the felt is to prevent abrasion to the bottom part of the frame. However, your present home made V support is a potential trouble maker. I suggest you remove them. As a rule never use any hard V shape support that prevents movement on both sides-only one side is allowed.
For leather go to a shoe cobbler or to a place where leather is sold by the yards. For the felt you can get it almost anywhere, especially in a DIY store or even some supermarkets or home-furnishing stores, carpet stores.
Strange. I have this same machine model for at least 4 years and I have NEVER broken a racquet. I have strung all the way up to 27/29 and the racquet held (string broke in 2 weeks thou from mis-hit). I did buy velcro strips to re-pad the metal that holds the frame. As a note I string at least 3 times per month for my club and my racquets.
can anyone take a photo of both side of their hand crank on the ST-200 my is moving funny ... want to see how it should look like
