Hello, Some stringers string two strings at a time. By `string,' I mean a piece of string, actually, going e.g. vertically. That is, some stringers put a string into a grommet, then leave the opposite grommet with the string, then continue for the next row, and then string these two strings at a time. It is sometimes said it is less precise. I don't really see why: you just need to turn more on the stringing machine (assuming a manual one), but stringing two strings at a time avoids rotating constantly the stringing machine on its axis, as you always put tension at the same place. What do you think about this (considering e.g. double flying clamps)? I also asked myself a question: assume you do that for 3 strings, and not 2. Would the 1st string of the three have less tension than the 2nd and 3rd, assuming double flying clamps? I'm not sure of that. Thanks.
run away from those stringers. we did that experiment before and the tension drop is around 10lbs over a 30lbs pull. TEN POUNDS.
This is nothing - my stringing teacher told me about a guy tried to weave all his crosses loose, tie on at the top, then pull the bottom one in an attempt to tension them all.
baaad!... in principle 2 strings pulled by 26lbs = 13lbs on each string.. and unless you have the musclepower type of frame where the grommet area is rounded so that string tension can be distributed more evenly.. doing it this way the tension wont be homogenous.. strange racquet!
Looking at the string bed of people that come to my store complaining about other stores' string job, I wouldn't be surprised if this was common practice in general sports stores..
Not saying I suggest the "pulling 2 at once" method, but I think if you use constant pulling type machine (e.g. drop weight), and do that for the main, I think the effect should be minimal, as the tension can be evenly distributed. However, I can see it will be hard to balance the tension for cross, as there are extra friction in between strings (main vs cross). Eitherway, I do not see it's really time saving any way, so not recommended.
I do this for the first 2 mains either side of middle as I only have flying clamps and don't want to clamp outside the racket to avoid scratches etc. I add +2lb to slightly compensate and then once started, go back to tensioning each string at original tension. This is on a drop weight machine and works pretty well for me.
I do not pull 2 at once, but I do not agree with your assumption either. Pulling 2 pieces vs 1 piece, is like pulling a longer piece, which should give you the same tension. The issue is, if you only pull once (2 piece), you usually do not fully stretch the string (due to double the length), therefore, it will result in lower tension. If you pull more than once, or use a consistant pulling machine, the effect will be minimized. However, such attempt will not save you time, which kills the meaning of "pulling 2 at once". In addition, pulling cross require to dealing with the extra friction between main vs. cross, which further contribute into the issue.
not exactly the same scenario, but should illustrate the problem with friction: [video=youtube;mHclmA7RPCU]http://www.youtube.com/watch?v=mHclmA7RPCU[/video]
Yes the tension loss is due to friction and not because there is 2 strings. Kwun, can you do a test on the tension loss on a double pull on the starting mains only? Be interesting to compare the effect of the racket shape on the tension loss.
If you dont have fixed clamps can you do the two starting mains any other way than pulling 2 at once?
this is the way i used to do it. [video=youtube;GN0RDEcSMz4]http://www.youtube.com/watch?v=GN0RDEcSMz4[/video]
Ok thanks for the video. What about the outer main when you have skilled two holes so the gap is too big for a flying clamp? Do you pull two at once then? Thanks
Yonex flying clamp is ok. check this video, around 5:15 or so. [video=youtube;Nt1IEXUuoGk]http://www.youtube.com/watch?v=Nt1IEXUuoGk[/video]
I usually do one pull for the last two mains with an extra 2 lbs. Also, if you have flying clamps and don't wan to clamp outside the frame, just get a piece of cardboard, cut a small slit in it for the string to fit, and put it between the clamp and frame. Works really well for me. I've experimented with clamping outside the bottom of the frame where sometimes the grommet sticks out a little bit. Haven't had any issues with that either.