Hi, It is possible to calibrate a stringing machine, without calibrator? I want to calibrate my drop weight machine, but I don’t have a calibrator. I have only “weight on spring” with scale from 1kg to 10kg- it’s look like calibrator. If 10kg from weight will be evenly 10kg (~22LBS) on strings? The best way to check it could be to compare indicate from that weight with indicate from good calibrator. I’ll hope that somebody can help me. Thanks in advance, Michal [FONT="]P.S. Sorry for my English [/FONT]
You can get some known weights, say the weight for bar bell, to calibrate the spring of your scale. Then use the scale to calibrate your stringing machine if you don't want to use a calibrator. BTW what kind of stringing machine are you using, drop weight or crank?
I have old drop weight machine. I calibrated spring using bottle with 5L water- it was about 5-5,1kg- so spring is ok. On Monday I tried calibrate my machine (I found some instuction) using that weight, but my opinion something is wrong. I think my weight indicate about ½ real tension. I restringed racket (MP55, BG65)- my weight showed about 5kg. In my opinion tension is 10kg (22 LBS).[FONT="] Any suggestion?[/FONT]
There's really nothing to calibrate for a drop weight machine, unless the weight is significantly damaged. Crank or electrical machines are a different story.
I agree with LB. 1 additional point. Since it is an old machine, I assume you have not used it for a long while. (ie. more than 1 year) You are worry about the machine parts might be rusted and it is not giving you the right tension, right? I would suggest you to take out some of the parts might be effected and clean it with some WD40 or oil. If you still want to cal the machine just for fun, here are 2 solutions from my students that I think are pretty good. 1) you need pully for this one. Mont a pully on the edge of the table. Get a string and 4-5 unopened 2 L bottle soda. Why? because they the soda inside is about as close to exactly 2 L without any additional measurement. 4*2L=8L. You have total of 8kg.(10kg if you use 5 bottles) Attach all the bottles together and tide it on a string. Mont the string over the pully to the machine. set the weight to 10kg then drop the weight. the bottles should barely lift off the ground. =>calibrated. 2) If you have 1 of those fish scale like the picture above. Get 3 bottles of unopend soda again. Test the weight on the scale by 1 bottle at a time to make sure the marking is correct. Once you are sure you have a good scale, secure the scale on something solid, tide a string to the other end of the scale, mont the string to the machine and adjust your weight to the correct weight marking. Drop the weight and check if the scale display the right tension. Good luck!
