In case you do not have a calibrator or lost the instruction, here it is. 1) get a calibrator (a digital fishing scale from local sporting good or walmart with hook or loop at the end will be good) 2) secure one end to a fixed object (like the far end of your stringing machine turn table) 3) tide a string to the other end of scale. 4) set the machine to desired tension and secure the string to the tension head. 5) crank or strat the tension head and see if the tension reading from tensioning head is same as the scale. is so, you are done (almose never on the first time) 6) adjust the lettle adjustment when tension head is released (or follow the manual)
Mmm, I could do with some help here. I use an oldish Pacific stringtronic XL The didgital readout is proportionally incorrect. I use fishing scales to check tension every time before the tensioning process. My machine pulls the tension consistantly. For instance if I want a tension of 24lb on the mains I have to set the digital readout to 36lb, on the crosses say 26/27lb I would have to increase the digital to 44lb. The machine doesn't have an external adjustment. Inside the box are two variable resistors, one I presume for lbs, other for kgs. I cant seem to get the readout correct.
With such an unreliable machine one mistake could be fatal. It would be better to fix the box, as having to constantly adjust the correct tension for every tension level can result in a wrong conversion inadvertently.
I only have to check the tension before starting the job. It pulls correctly everytime. It only takes a couple of minutes before setting up to check the tension head. I know that for 22lb I just need to set it to 36lb on the readout.
What happens if you require 23lbs, 24lbs 26lbs, 28lbs, 29lbs, 30lbs, etc? As it is not something simple like 1 multiple of say a required tension of 24lbs x 1.5 = 36lbs, it would be a nightmare having to convert each tension for every racquet. Why don't you get the box fixed? That solves the fundamental problem.
I use the same routine as above for other tensions. I would love to get it fixed but cant find anyone to sort it. I'll invest in a new machine before long when I decide which type I prefer. I've got used to the glide bars and find them very quick and easy to manipulate.
quick question If you calibrate a drop weight machine, since they come with those handy sticker things to put on the rod, do you only need to do it once? ie calibrate to 20lbs then the sticker with its equally spaced markings will tell you naturally where to set the weight for the other tensions? I have a feeling my machine (drop weight) is off, but I am not too bothered as long as I can be sure that the cross strings are strung at 2 lb higher tension to ensure the headshape is maintained. Currently to achieve what i feel is 24 lbs tension I set the machine to do 20 for mains and 22 for crosses, am I correct in assuming that since it seems 2lb off (on my machine) then all the markings on the stickers are 2lb off? Also is it ok for me to string top to bottom for cross strings? I think I read master silentheart and sir dinkalot don't mind doing so, if it's ok for those guys I don't mind too much since I would never go higher than 25/26 lbs for tension. Thanks guy, appreciate all your effort and fast response that is so typical for the users of this forum.
1) you need to do a initial tension calibration for drop weight. just for a piece of mind. 2) the tension is not in equal distance. in fact, higher the tension, shorter the distance. because there is weight on the rod even without weight 3) string from top down will give you more protection on miss hit near the top of the frame. throat up will give you a little better playability. my suggestion is to try both out and let your hand decide. good luck
argh, i just bought the fishing scales from argos to see if my machine and eagnas calibrator were both out and incorrect and it has confirmed my suspicion, the machine is pulling a lot more than the markings indicate!! I have know found out that my last racket strung (3rd try on my fav racket armortec 800 offensive) is strung with 24 mains and 25 for crosses, but the frame remained in shape? (as i checked this immediately afterwards) is it gonna be ok? should i cut out the strings and redo it? It is still in the right shape (the head i mean) and I strung it about a month ago and played with it since. Big thanks to the responses especially master silentheart whose wise words indeed ring true, calibrate your drop weight machine!!
Don't worry too much about the 24X25 right now. It is not going to hurt your racquet too much. If it will break, it would have broken already. Just string it with the 2lb or 10% difference next time. I was lucky to have access to a lab before when I was a grad student. I know my scale is good. Anyway, good luck and enjoy the stringing. Dear Master Drifit, You must be very good to be able to misshit at bottom frame. I am not that good...
yeh it's ok now, i've calibrated the damn thing, seems 2lb out, can't believe it... I can definitely recommend the £6 fish scales from argos as a worthwhile buy. Thanks again guys.