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Donny0627
09-25-2010, 05:37 PM
I see a lot of people on these boards talking about calibrating ther stringing machines with a fish scale. i have a gamma 602 dropweight(floating clamps), how do i calibrate this with a fish scale?

esgee48
09-25-2010, 06:40 PM
2nd answer first: No, a digital food scale does not cover the range of tensions avalaible for a stringing machine.

You do need to calibrate a lock out machine whenever you suspect that the spring is off. You normally do not calibrate drop weight machines unless you did something to the tensioning rod such as replace it or damage the tension decal scale on the rod.

I recommended that you purchase a luggage scale which goes to at least 70 pounds for calibration purposes from eB. Tie one end to a support post of the stringer, attach string to other end and tension. See what the scale says. You may need to support the scale with a piece of wood, but it is relatively easy to do.

rich s
09-25-2010, 08:40 PM
The 602 and all newer Progression and X series Dropweights have the scale stamped into the rod.

I had a 602FC for about 9 or 10 years.... never calibrated it, never felt a need to, there is nothing really to go out of calibration...... stringbed stiffness was consistant after stringing.

Unless you have a crank or electronic that does not re-calibrate itself with each power up/down I wouldn't waste my time calibrating a dropweight (especially one with the scale stamped on the drop arm)

Irvin
09-26-2010, 10:55 AM
You don't need to calibrate the dropweight but you should be sure the tension is correct. Some times the rod is not stamped or labeled correctly and you tension will be off. You may also be using the wrong side of the weight to read your tension which will also throw off your tension.

Irvin

Donny0627
09-26-2010, 01:40 PM
thanks to all who answered(saving me the cost of calibrating it)

and Irvin, I am positive that I am reading the right scale, as one scale only goes to 20, and one only goes to like 40 or 50. the only one tht does seem practical is the one i use, which goes much higher(i am not near my stringer right now so idk), but probly somewhere around 80-90.

Irvin
09-26-2010, 01:45 PM
^^ That means you have two different sets of weights you can install on the bar to get the reading. I am talking about which side of the weight you read the number on. It should be read on the bottom but some people read it on the top. If you have two sets of weights now are you sure you have the correct ones on? All I am saying it is good to check them once if you have the ability to do that. Then you know it is right. To my knowledge there is no claibration procedure, but I could be mistaken.

Irvin

Radicalized
09-26-2010, 03:08 PM
This is a general statement for those reading the thread. The scale should be stamped into the bar on that model. The top scale runs to 90 lbs. for tennis. The bottom runs to 20 lbs. for badminton (using the smaller part of the weight only). The "0" point of the scale is located at the point that it enters the gripper mechanism. The knob is on the side of the gripper. The tension setting is read on the side of the knob. The only adjustments on this machine are the position of the weight, and in an extremely minor way, the position of the racquet head on the turntable in relation to the distance from the gripper mechanism. If all of the above are manufactured properly, they should all be the same. It would require a major defect, not just a loose screw, bad electronic mechanism, or bad spring, for example, to throw it off.

Here's a good one. Check the Gamma X-2 and X-6 manuals (maybe others with the drop weight, too). For the "Installing the Drop Weight" section, the text is correct, but the photo shows the weight being held to be installed backwards. What man READS instructions? :???: At least shoot the picture with it in the right orientation. At least others I've seen are correct. Be careful new X-2 and X-6 users.

aznfatmonkey
09-27-2010, 06:32 PM
I have a Eagnas Combo 910, and recently I have encountered a problem. When I set the tension to 60, it reads 61 on the scale. When I set it to 66 (the tension I string my racquet at), it reads 64. Does anybody why? Thanks.

airman88
09-27-2010, 10:00 PM
The numbers don't really mean anything anyway, they are benchmarks. Just find reference tensions that suit the feel you like and stick to them. Or you can try calibrating down and back up and see if it fixes it. But the lockout mechanism is most likely just letting out more tension at the 66 than at 60ish by the time you look at the scale. You could try using kevlar with your calibrator.

aznfatmonkey
10-01-2010, 03:05 PM
Actually, it's not because the tension dropped more by the time i checked it because i look at the maximum tension that it goes to. I understand that it's just a reference tension, but I'm just asking in case i string for somebody else. Does anybody know another reason why the tension reading is off?

struggle
10-01-2010, 03:51 PM
Actually, it's not because the tension dropped more by the time i checked it because i look at the maximum tension that it goes to. I understand that it's just a reference tension, but I'm just asking in case i string for somebody else. Does anybody know another reason why the tension reading is off?

i had varied tensions when trying to calibrate my 910 as well.

what gave me the best (reliable in my mind) results:

I calibrated through a racket and then simulated that with a dowel, shims etc..
2nd, i brought the tension head as close to the racket as possible, and make sure to get the string down into the gripper, not near the top edge.

both of these gave me consistent, repeatable results and in the end my machine seemed on the money from the factory.

edit: and definitely use kevlar. i also have three different calibrators.....when they end up roughly the same i get alot more confident.

aznfatmonkey
10-01-2010, 05:18 PM
I don't understand why that would matter if I'm looking at the maximum tension. I look at the tension the calibrator is at the moment the tension head locks out. None of the above factors should matter because at that instant, the tension should be the same no matter the factors. Using kevlar and putting the tension head close should only affect the stretching of the string after the tension head locks out. BTW, i use an electronic scale.

struggle
10-02-2010, 06:22 AM
I don't understand why that would matter if I'm looking at the maximum tension. I look at the tension the calibrator is at the moment the tension head locks out. None of the above factors should matter because at that instant, the tension should be the same no matter the factors. Using kevlar and putting the tension head close should only affect the stretching of the string after the tension head locks out. BTW, i use an electronic scale.

just telling you what worked for me. but i see your point.

Irvin
10-02-2010, 01:40 PM
I don't understand why that would matter if I'm looking at the maximum tension. I look at the tension the calibrator is at the moment the tension head locks out. None of the above factors should matter because at that instant, the tension should be the same no matter the factors. Using kevlar and putting the tension head close should only affect the stretching of the string after the tension head locks out. BTW, i use an electronic scale.

When the tension head locks out leads me to believe you are using a lock out stringer. After the tensioner lock out there is no more tensioning just holding. The longer the string and the more the string stretches the less tension you will have.

Irvin

aznfatmonkey
10-04-2010, 04:15 PM
When the tension head locks out leads me to believe you are using a lock out stringer. After the tensioner lock out there is no more tensioning just holding. The longer the string and the more the string stretches the less tension you will have.

Irvin

Yes, I understand this. But at the instant that the tensioner locks out, the tension should read the same regardless of all other factors (type of string, length of string, etc). My question is why my calibrator is reading 64 lbs at that instant when I string at 66, but correctly, at 61, when I string at 60.

struggle
10-04-2010, 04:54 PM
post a pic of how you are mounting the scale. it needs to simulate the angles encountered while stringing a racket.

Irvin
10-04-2010, 04:56 PM
Yes, I understand this. But at the instant that the tensioner locks out, the tension should read the same regardless of all other factors (type of string, length of string, etc). My question is why my calibrator is reading 64 lbs at that instant when I string at 66, but correctly, at 61, when I string at 60.

Neither sounds correct to me. Problems could be with either the tension head or the calibrator. I have no idea which one. Then again it could be a little of both.

Irvin

aznfatmonkey
10-04-2010, 10:51 PM
Oops, I don't know why I put 61 would be correct :confused:. Either way, the difference in tension between 60 and 66 should be 6 lbs, not 3 lbs, as my calibrator is showing. So do you think I should get another calibrator to test it? If the problems lies with the tensioner, would I have to deal with Eagnas customer service?:shock:

Irvin
10-05-2010, 04:55 AM
3 pounds off seems odd to me. That is one rotation of the tension knob, but may just be coincidence. What happens when you go 6 pounds down. Check a few more. Another calibration tool may help also.

There could be something sticking in the mechanical tensioner I would clean and check that real good.

Irvin

Gamma Tech
10-05-2010, 06:48 AM
Oops, I don't know why I put 61 would be correct :confused:. Either way, the difference in tension between 60 and 66 should be 6 lbs, not 3 lbs, as my calibrator is showing. So do you think I should get another calibrator to test it? If the problems lies with the tensioner, would I have to deal with Eagnas customer service?:shock:

is you tension off at a low tension (~25lbs) and high (~75lbs)? if these 2 are accurate then all the tensions in-between should be. it is better to look at the whole picture than a tiny snap shot.
bret