knob doesn't match scale gamma x-st

alexmcnab

Rookie
Hi, I have a Gamma x-st. The number on the knob doesn't match with the gauge - ie. in this example 54 lbs should match with 0 on the knob.
I tried loosening the grub screw and rotating the knob but both the knob and the gauge still move in sync so no help. I tried pulling on the knob with the grub screw removed but it wouldn't budge. Any ideas apart from pulling on knob jokes :)
 

Irvin

Talk Tennis Guru
@Gamma Tech

If it were me I would adjust the rotation knob to line up the 0 on the knob when I adjusted tension and forget about the 3# increment being off. Gamma Tech may have a simple solution for lining up the marks. You could also call Tennis Machine Monday.
 

struggle

Legend
That "scale" is tiny. I'd go with (and calibrate to, if you do such) the knob which is much more fine adjustment than the linear scale which is guess, at best.
 

First Serve

Rookie
I have the same Gamma Linear Gripper.

Another photo with the knob aligned with Zero (0) would help to see how far off the scale is off. Since it seems moving turn knob to zero is a 1/4 turn away, it would be interesting to see how much the tick marks are off. From here it seems real close.
 

uk_skippy

Hall of Fame
The other thing is that the line on the adjuster is thicker than the gauge, which means it will never fully match. Almost like you'd have to line 1 edge of the adjuster with the gauge.
 

esgee48

G.O.A.T.
OP - you are sort of obsessing over nada. In the LO universe, ±½ lb is a non issue since your cranking speed also has an effect on when the tension head locks out. Pull speed also affect eCP, but not to the same extent as a LO. [I know this is like a "pot calling the kettle black" o_O. I would worry more about calibration and consistency.]
 

alexmcnab

Rookie
"obsessing"...good grief.
I've already said it's not a big problem but I'd like to have it back to where it originally was which was spot on.
Rather than talk about calibration or consistency of pull speed - It's ok to say "I don't know"
I thought I would ask here in case there was an easy fix that might also help people in the future.
I'll ask Gamma Europe and report back when I hear something.
 

First Serve

Rookie
It is really close, probably about 1/2 lb.
And yes, I know it is not a problem and doesn't really matter in the scheme of things.
But I would like it to be right which must be possible. The grub screw seems to have no purpose.
Thanks Alex. I understand your point. For my same exact gripper, it seems right on when I have the knob at Zero and indicates a whole tension number, not a fraction as in your case. It might be interesting to note, when I use the Gamma calibrator and the LO is set at 50 or 55 pounds with the knob at Zero it reads dead on the calibrator. I use 50 and 55 lbs because the calibrator also has tick marks as does (obviously) the LO device.

Have you used a calibrator as a point of reference?
 

alexmcnab

Rookie
Thanks Alex. I understand your point. For my same exact gripper, it seems right on when I have the knob at Zero and indicates a whole tension number, not a fraction as in your case. It might be interesting to note, when I use the Gamma calibrator and the LO is set at 50 or 55 pounds with the knob at Zero it reads dead on the calibrator. I use 50 and 55 lbs because the calibrator also has tick marks as does (obviously) the LO device.

Have you used a calibrator as a point of reference?
Yes, I checked 50 and 60lbs on the RAB barrel one, some digital fish scales and Goat Stringer's Piab(I think that's what it's called) and they were all pretty accurate.
 

Wes

Professional
Hi, I have a Gamma x-st. The number on the knob doesn't match with the gauge - ie. in this example 54 lbs should match with 0 on the knob.
I tried loosening the grub screw and rotating the knob but both the knob and the gauge still move in sync so no help. I tried pulling on the knob with the grub screw removed but it wouldn't budge. Any ideas apart from pulling on knob jokes :)
It is really close, probably about 1/2 lb.
And yes, I know it is not a problem and doesn't really matter in the scheme of things.
But I would like it to be right which must be possible. The grub screw seems to have no purpose.
It is possible - precisely because the "grub screw" does serve a purpose.

I've already said it's not a big problem but I'd like to have it back to where it originally was which was spot on.
Rather than talk about calibration or consistency of pull speed - It's ok to say "I don't know"
I thought I would ask here in case there was an easy fix that might also help people in the future.
Is it ok for me to say "I do know"? ;)
It is an easy fix. Hopefully this will help you and others in the future. :cool:

Gamma Europe don't know how to adjust it.
I've also failed to find out the purpose of the grub screw.
The set screw (or "grub screw" as you call it) does serve a purpose.
When I have some extra time, I'll dig out the crank tensioner for my 6004 and try making a video of the adjustments.
@alexmcnab,
Here you go. Sorry it took so long. I've been pretty busy lately.

You would do well to watch this entire process, however, 35:00-46:40 specifically addresses the adjustment of the "0-1-2 collar".
Note: this collar must be adjusted BEFORE you actually calibrate the tensioner.
Otherwise, the numbers are never going to match up - the way they are supposed to.


The other thing is that the line on the adjuster is thicker than the gauge, which means it will never fully match. Almost like you'd have to line 1 edge of the adjuster with the gauge.
This is addressed from 36:15-39:25.
 

Wes

Professional
For my same exact gripper, it seems right on when I have the knob at Zero and indicates a whole tension number, not a fraction as in your case. It might be interesting to note, when I use the Gamma calibrator and the LO is set at 50 or 55 pounds with the knob at Zero it reads dead on the calibrator. I use 50 and 55 lbs because the calibrator also has tick marks as does (obviously) the LO device.
@First Serve, that's not how the numbers should be.
When your Gamma LO tensioner is set at #50, then the knob should actually be at "2", not at "0".
When your Gamma LO tensioner is set at #55, then the knob should actually be at "1". Again, not at "0".

Since neither "50", nor "55" are numbers printed on the scale (nor have a hash mark on the scale), those tensions/values should not have the knob at "0".
Only numbers that are printed on the scale (and the "in between" hash mark values) should have the knob at "0". Every other value/tension should have the knob at "1" or "2".

Therefore, when your tensioner is set at #60, then the knob should actually be at "0".
 

First Serve

Rookie
@First Serve, that's not how the numbers should be.
When your Gamma LO tensioner is set at #50, then the knob should actually be at "2", not at "0".
When your Gamma LO tensioner is set at #55, then the knob should actually be at "1". Again, not at "0".

Since neither "50", nor "55" are numbers printed on the scale (nor have a hash mark on the scale), those tensions/values should not have the knob at "0".
Only numbers that are printed on the scale (and the "in between" hash mark values) should have the knob at "0". Every other value/tension should have the knob at "1" or "2".

Therefore, when your tensioner is set at #60, then the knob should actually be at "0".
@Wes, I switched my Gamma LO to a Wise2086 TH about 2 years ago. Sorry you are right. 55 and 50 lbs aren't probably tick marks on the knob.

I meant basically to illustrate that my LO which I keep as a spare is right on the money. Meaning What the knob should read, the calibrator shows.
 

Wes

Professional
@Wes, I switched my Gamma LO to a Wise2086 TH about 2 years ago. Sorry you are right. 55 and 50 lbs aren't probably tick marks on the knob.

I meant basically to illustrate that my LO which I keep as a spare is right on the money. Meaning What the knob should read, the calibrator shows.
Alrighty. Fair enough.
I just think your previous statement has the potential to lead others, who are attempting to troubleshoot, to incorrect/false conclusions.
Hopefully, I've cleared that up.
 

First Serve

Rookie
I agree, the way the Gamma knob works, that if the tick mark reads 48 lbs for instance , then 49 lbs is 48 +1 tick mark turn, 50 is 2 and then 51 is a tick mark. Sorry if I caused confusion.
 

alexmcnab

Rookie
Thanks Wes, interesting. I did know how to calibrate.
However, the "0,1,2 collar" on my machine does not rotate independently to the knob when the set screw is loosened (or even removed). I'm reluctant to grab it with pliers and see if it moves.
 

struggle

Legend
Thanks Wes, interesting. I did know how to calibrate.
However, the "0,1,2 collar" on my machine does not rotate independently to the knob when the set screw is loosened (or even removed). I'm reluctant to grab it with pliers and see if it moves.
perhaps turn it all the way "Loose"/zero and see if the stopped position will free the knob (set screw loose, without pliers etc).

I had assumed there would be a flat spot or hole on the rod where the set screw goes (so knob doesn't twist loose) and that all calibration would be done
via the normal calibration methods and so from there the knob should "jive" as it would have been calibrate at a known number corresponding to 0,1 or 2 on the knob. BUT......I've had two LO machines but never had to calibrate either of them, barely even checked them as they were always "spot on" (in lockout terms...)
 

Irvin

Talk Tennis Guru
Thanks Wes, interesting. I did know how to calibrate.
However, the "0,1,2 collar" on my machine does not rotate independently to the knob when the set screw is loosened (or even removed). I'm reluctant to grab it with pliers and see if it moves.
Why not call JC at Tennis Machines and ask?
 

Irvin

Talk Tennis Guru
£3 a minute from uk

Sent from my HD1903 using Tapatalk
Email them it may take longer to get a response but any response is good news. I doubt your issue is anything to worry about anyway so it doesn’t matter how long it takes.

Also since I’m not in the UK and have never tried don’t know if this works or not but it this may work.

 
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Irvin

Talk Tennis Guru
£3 a minute from uk

Sent from my HD1903 using Tapatalk
Just messaged a friend that lives in Liverpool. He said he uses Messenger app to make free audio and video calls. There is a phone and camera icon in the upper right corner of the app and it free.
 

Wes

Professional
However, the "0,1,2 collar" on my machine does not rotate independently to the knob when the set screw is loosened (or even removed). I'm reluctant to grab it with pliers and see if it moves.
@alexmcnab,
Yeah, I'd be reluctant to be grabbing it with pliers, or anything like that, too.
So, before you go resorting to anything harsh, maybe try this... completely remove the set screw from the "0-1-2 collar" and set it aside.

Next, spray some WD-40 (using that tiny straw that is included) along each side of the collar, as well as spraying some down into the hole where the set screw had been.
Wait a several hours (or, if need be, overnight) for the WD-40 to penetrate. Then go back and fiddle with the collar to see if it has "broken free".

FWIW... upon reading that your collar will not rotate freely (despite the set screw being removed) I began to wonder if, for some crazy reason, some of Gamma's lockout tensioners could possibly be made a little differently from each other (i.e. say, a unit manufactured 2 years ago vs. a unit manufactured 10+ years ago). :unsure:

So, I went and pulled out yet another Gamma LO tensioner (that belongs to a fairly new Gamma X-ST) to see if it's "0-1-2 collar" would spin freely or not.
I wanted to check and see if that one, perhaps, was going to be "locked up" like yours.

Nope. Once the set screw is loosened, it spins just like the collar in my video does.
The LO tensioner in my video is the one that came on my 6004. Obviously, it's collar spins freely.

If you try the WD-40, let us know how things go.

Cheers,
Wes
 

alexmcnab

Rookie
Update- I tried wd40, didn't help. Emailed John at Gamma, he replied but didn't answer my query. I tried explaining the situation more clearly and await his response. I will report here when I get something.

In the meantime, I've come up with a temporary (maybe permanent) solution. I put a sticky label around the "0,1,2 collar" and matched it up so 0 now matches 54lb, 57lb etc. so everything now aligns perfectly. Not sure why I didn't think of it earlier.

By coincidence, the 0 lines up with middle of the set screw, so I'm using the set screw as 0 and written the 1 and 2 on the label.
 

uk_skippy

Hall of Fame
I'll try emailing, I've already tried gamma europe but no luck
Only just seen this post, but within UK the offiicial Gamma distributor, and machine service agent is Apollo Leisure (01202 812000) Give them a call. They have the best service engineers in the UK, while Ray is know wordlwide; good friends with Albert Lee too.
 

Wes

Professional
Update- I tried wd40, didn't help. Emailed John at Gamma, he replied but didn't answer my query. I tried explaining the situation more clearly and await his response. I will report here when I get something.

By coincidence, the 0 lines up with middle of the set screw, so I'm using the set screw as 0 and written the 1 and 2 on the label.
Sorry to hear that the WD-40 didn't do anything. :(

After reading that your set screw lines up with the "0", I now have a suspicious feeling that, perhaps, your tensioner may not actually be made by Gamma.
I'm thinking you may have some other brand tensioner on your machine (or, at least, that the knob/collar portion was robbed from some other machine).

The reason that I'm now suspicious is because that is not where the set screw is located on a Gamma crank/tensioner.
On BOTH of my Gamma cranks, the set screw on the "0-1-2 collar" is exactly half way between the "0" and the "2" (where it's out of the way).
Think about it for just a moment. It wouldn't make sense to put the set screw RIGHT where the "0" is, since the "0", "1", and "2" all have a little white (indicator) line RIGHT where the number is. Having the set screw there would leave little room for that white line/number.

By any chance, did you buy this machine used?
Or, did you buy the machine brand new (from a reputable dealer)?

That set screw, being in the same spot as where the "0" is located, just doesn't add up. :unsure:
 

alexmcnab

Rookie
I bought it new from Gamma Europe.
The original collar was "0,1,2" with "0" aligned to 54lbs.
I put a sticky label around the collar covering the numbers.
With the machine set to 54 I wrote "0,1,2" on the label where "0" aligned to 54
I realised that the set screw was right under where I'd written the "0" so I put a new label on that goes almost all the way round so I'm now using "set screw as 0, 1,2" .
 

Irvin

Talk Tennis Guru
The quickest way to determine if it’s a Gamma LO is to look for the string guide / string roller. Some may think it is a diablo but it only looks like a diablo.
 

alexmcnab

Rookie
The quickest way to determine if it’s a Gamma LO is to look for the string guide / string roller. Some may think it is a diablo but it only looks like a diablo.
Is that a question or a statement? Either way I don't understand what you are saying.
 

Irvin

Talk Tennis Guru
Is that a question or a statement? Either way I don't understand what you are saying.
I doubt there’s a chance you do not have a Gamma tensioner but there’s a quick way to identify them. The Gamma LOs have a string guide you wrap the string around before it go into the gripper. Does your tensioner have the string guide?
 

First Serve

Rookie
@Irvin
The quickest way to determine if it’s a Gamma LO is to look for the string guide / string roller. Some may think it is a diablo but it only looks like a diablo.
I am curious, why dont you think the Diablo looking feature on the Gamma LO is NOT a Diablo? Because it rotates?
 

jim e

Legend
A Diablo will not rotate. It not only guides the string on the proper position on each grab of the linnear grip plates , but also takes a lot of the strings tension away from the gripper plates as well. The ones that rotate will give a higher tension at the plates of the gripper, but it does guide the string in the proper angle to the plates.
 

First Serve

Rookie
A Diablo will not rotate. It not only guides the string on the proper position on each grab of the linnear grip plates , but also takes a lot of the strings tension away from the gripper plates as well. The ones that rotate will give a higher tension at the plates of the gripper, but it does guide the string in the proper angle to the plates.
Thanks for explaining that to me. I guess I need to dig out my statics book to understand this for myself. Pulleys rotate too but there is a mechanical advantage to be gained by them. I am sorry I need to look into this further.

I have changed my LO to a Wise, but I do recall that once I wrapped the string around the "roller", the what I thought was a Diablo didnt rotate anymore and therefore acted like a Diablo, i..e a pulley. thereby reducing the force at the gripper. But thanks again for the explanation.
 
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Irvin

Talk Tennis Guru
@Irvin


I am curious, why dont you think the Diablo looking feature on the Gamma LO is NOT a Diablo? Because it rotates?
Correct a Diablo does not rotate a string guide does. Another term Gamma uses is a string roller. If the guide didn't roll there would not be the same tension on both sides.
 

Irvin

Talk Tennis Guru
I have changed my LO to a Wise, but I do recall that once I wrapped the string around the "roller", the what I thought was a Diablo didnt rotate anymore and therefore acted like a Diablo, i..e a pulley. thereby reducing the force at the gripper. But thanks again for the explanation.
If the roller stops rotating on a Gamma LO there will be more friction and tension on the gripper will be reduced. If tension on the gripper if reduced it takes more tension on the racket side of the roller to lift the gripper assembly and lock out. So a properly adjusted tension head will pull at an increased tension.
 

alexmcnab

Rookie
I doubt there’s a chance you do not have a Gamma tensioner but there’s a quick way to identify them. The Gamma LOs have a string guide you wrap the string around before it go into the gripper. Does your tensioner have the string guide?
Yes it does
 

Wes

Professional
Thanks for making this video! I brought home a used Toalson about a month ago. There wasn't a manual with it. I appreciate the time you took to make the video. Thanks again!
(y)
You're very welcome.

The whole point was to help others, just like you, out - since the manuals that come with most machines are notoriously lacking in proper instruction.

The goal was to make a complete and thorough A to Z video (especially for those who might not have a single clue how to start the process), walking you through the entire process step by step - including calibrator usage (for constant pull and lockout machines), how to properly orient the machine/clamps for the purposes of calibration, as well as the actual adjustments themselves.

Hopefully, the Toalson is similar enough to the Gamma unit that it still helps out.

Thanks again for the acknowledgment. :)

If you enjoyed this sort of "deep dive" instructional, I'll also have something in the near future regarding different methods for starting mains (with fixed clamps).
It will cover the advantages/disadvantages of 8 possible methods for starting your mains.
 

LocNetMonster

Professional
Hopefully, the Toalson is similar enough to the Gamma unit that it still helps out.
Minus the diablo, the tensioner unit itself is identical to yours. I just need a find or make a diablo and I'll be a happy camper. Thanks again for your effort!
 

Irvin

Talk Tennis Guru
Wes’s tensioner does not have a diablo but his Wise does. His Gamma Lockout has a string guide. A diablo will not be useful on a lockout machine. I doubt you will find it easy to mount a string guide on just any lockout.
 
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