Clamps moving a lot

KaiserW

Hall of Fame
#1
I have a Gamma Progression 2, the new model is 602 FC. Last few times I strung my clamps are moving a ridiculous amount when I do first 6 mains or so. I am talking like moving 3". So I decided to take apart and clean bases and rails still no luck. Machine is probably 20 years old.

Any thoughts on what else I can try? Think it might be time to bite the bullet and but a new machine. I also looked at Gamma website to price new base clamps and don't even see any.
 

Dags

Professional
#3
Is the string slipping in the clamp? Or are you saying that the base clamp isn't locking properly, and the clamp itself is moving whilst the string stays secure in the jaws?
 

Dags

Professional
#5
If it's the base clamp that's moving, then backing it up with a starting clamp isn't going to help in this scenario. That you've taken it apart suggests you've got a good understanding of how it all sits together; the only thing I'll mention is that my base clamps get tightened with an Allen key without the need to disassemble anything. Is there a chance you've overlooked something like that?
 

KaiserW

Hall of Fame
#6
No I don't have an Allen wrench or screw to tighten. One thing I noticed in the knob assembly (old school knob tightens the clamp) was there is a roller bearing assembly where the ring of the assembly was bent. Not sure if this would have anything to do with it.
 
#7
...
I was going to tell you how to cheaply rebuild a worn or damaged base clamp, but it sounds like you just need to read the manual and do a simple adjustment.
 
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#9
It sounds like the base clamp probably just need adjusted. Never, never, never, remove the base clamp lever and try to adjust the clamp from the top, teh sadjustment should be made from underneath. Leave the base clamp on the turntable and look under your turntable and you will see holes about the size of a silver dollar. Slide the base clamp over the hole and you will see a 17mm lock nut. Your machine would have come with a 17mm socket. It is silver hex shaped, about 2" long and looks like a bent sheet metal spark plug socket. If it went missing...any 17mm socket is fine. Turn the lock nut clockwise, slowly. While turning use your free hand to thumb the clamp lever and you will feel it tighten up. Every once in a while the clamp may feel like it is binding when moving it back and forth. If that happens just turn the lock nut in the opposite direction. If you continue to have problems, message me.
 
#10
Thanks I will check out. I bought the machine used and didn't come with the socket.

I don't recall seeing this lock nut but maybe I missed it. Would all machines have this? My model is over 20 years old Progression II.
 
#11
Thanks I will check out. I bought the machine used and didn't come with the socket.

I don't recall seeing this lock nut but maybe I missed it. Would all machines have this? My model is over 20 years old Progression II.
If it is 20 years old I would replace the locknut.
 
#16
It sounds like the base clamp probably just need adjusted. Never, never, never, remove the base clamp lever and try to adjust the clamp from the top, teh sadjustment should be made from underneath. Leave the base clamp on the turntable and look under your turntable and you will see holes about the size of a silver dollar. Slide the base clamp over the hole and you will see a 17mm lock nut. Your machine would have come with a 17mm socket. It is silver hex shaped, about 2" long and looks like a bent sheet metal spark plug socket. If it went missing...any 17mm socket is fine. Turn the lock nut clockwise, slowly. While turning use your free hand to thumb the clamp lever and you will feel it tighten up. Every once in a while the clamp may feel like it is binding when moving it back and forth. If that happens just turn the lock nut in the opposite direction. If you continue to have problems, message me.
Hi tried to message you but it would allow me to. I called Gamma and they are sending a message to have John call me.
Not sure if that is you but I look forward to resolving this issue.
 
#22
The diameter has been posted here in the past. 12 mm diameter shafts unless they changed it recently [which I doubt.] You need to talk to @Gamma Tech about replacements. Or contact them directly via their web site, Gammasports.com.The other manufacturers may have clamps that would fit if they are the right diameter and height. Since these are double action, shouldn't be an issue. Good Luck.
 

KaiserW

Hall of Fame
#24
Is it your clamps or your clamp bases that are shot?
At first I thought bases but now I think the clamps. The base does not move in position on the rail, the clamp is slipping/sliding towards the tension head when releasing tension. Considering clamps aren't cheap maybe I am better off buying a new machine. It is almost 20 years old.
 

KaiserW

Hall of Fame
#25
The diameter has been posted here in the past. 12 mm diameter shafts unless they changed it recently [which I doubt.] You need to talk to @Gamma Tech about replacements. Or contact them directly via their web site, Gammasports.com.The other manufacturers may have clamps that would fit if they are the right diameter and height. Since these are double action, shouldn't be an issue. Good Luck.
Thanks
 

KaiserW

Hall of Fame
#26
At first I thought bases but now I think the clamps. The base does not move in position on the rail, the clamp is slipping/sliding towards the tension head when releasing tension. Considering clamps aren't cheap maybe I am better off buying a new machine. It is almost 20 years old.
Given this explanation looking for opinions if others think it is the clamps and not the bases. Clamp base does not move further down the rails, it just swivels about 2" towards the tension head.

I would hate to buy new clamps and it not fix the issue.

Thanks everyone for the help so far this is very frustrating not knowing the exact issue.
 
C

Chadillac

Guest
#27
There should be a nut locking down the clamp on the bottom under base (maybe needs a washer). Clamps are simple, they attach to the machine. As long as your tension is fine just get new base clamps (both parts). Attach and you got a new machine
 

KaiserW

Hall of Fame
#28
There should be a nut locking down the clamp on the bottom under base (maybe needs a washer). Clamps are simple, they attach to the machine. As long as your tension is fine just get new base clamps (both parts). Attach and you got a new machine
My machine doesn't have that please see above pics I posted. I think Gamma Tech said no bases are available for mine it is the original 602 FC.
 
#29
The base does not move in position on the rail, the clamp is slipping/sliding towards the tension head when releasing tension.
Does not sound possible. Defies the laws of physics. Only direction it could possible slip would be away from the tension head. Please post video.
 

KaiserW

Hall of Fame
#30
Does not sound possible. Defies the laws of physics. Only direction it could possible slip would be away from the tension head. Please post video.
Maybe I should clarify I had one main clamped and tensioned the other main. When I released tension on the main closest to the tension head it did move away from the tension head while the other clamped main already tensioned moved towards the tension head. So both clamps are moving towards each.
 
#31
It seems to me your clamp bases are slipping. And yet, as recently as post #26, you (OP) are speculating that the clamps may be the problem. There should not be any question. You really should post a video.
 

mmk

Hall of Fame
#36
That almost looks like there is something missing in the base clamps. The actual base doesn't move linearly, so it is locked in place, but the way it rotates around the central bolt just looks like something is the wrong size or is missing in the body of the base clamp.
 
#38
A couple observations:

1. I have never attempted to begin stringing a racquet in this manner. After tensioning the first main on the right side I expected to see you install and tension the second right side main. After this, I would expect you to move over to the left side and install 3 strings in a row. What you are doing puts considerably more strain on the clamp base which has minimal contact with the track at this point in the string job because it is angled across the track. You might even want to consider installing 3 or 4 right side mains before transferring if that is what it takes to get the right side clamp base in maximum contact with the track.

2. I don't have a drop weight machine but listening to all the cranking you are doing is making me wonder how many pounds of tension are you applying?
 
#39
I have a Gamma Progression 2, the new model is 602 FC. Last few times I strung my clamps are moving a ridiculous amount when I do first 6 mains or so. I am talking like moving 3". So I decided to take apart and clean bases and rails still no luck. Machine is probably 20 years old.

Any thoughts on what else I can try? Think it might be time to bite the bullet and but a new machine. I also looked at Gamma website to price new base clamps and don't even see any.
@KaiserW,

How did you clean the clamp bases and the rails?

I had a similar issue with a very old machine. Clamp bases would slip at medium to higher tensions (above 50lbs).

I removed clamp bases and rails. Soaked the bases and rails in boiling hot water and strong dishwashing detergent for at least 30 mins. I then scrubbed them using a stiff nylon brush and steel wool. Then heavy wipe with white paper towels. Kept at it with boiling hot water and detergent until no more dark coloured residue on the paper towels.

After this, a proper clean of all components and wipe with Isopropyl alchohol.

Reinstalled everything and no more slippages even up to 65lbs of tension.

I repeat this cleaning process after every 50 restrings.

Also, I start stringing Mains using a Yusuki method with the help of a Starting Clamp and that seems to help a lot.
 
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am1899

Hall of Fame
#40
Yup, it appears your bases are slipping. I agree that the starting method may be exacerbating this problem.

Beyond that, the first thing I’d be looking at is cleaning the rails and bases. Next, I’d see about what adjustment can be made to have the bases grip the rails tighter when you lock them. If all that fails, I’d be looking into a new set of bases, and maybe a new set of rails, too.
 
#41
When I clean the rails and bases on my machine I clean the mating surfaces with a product I found in a hardware store called "oops" (a fairly strong solvent) and remove the residue of the solvent with isopropyl alchohol. I am very skeptical about using water to clean but I have to admit, the alcohol contains water, so my skepticism may be unwarranted. I'd just be cautious about getting ferrous materials wet.
 
#42
When I clean the rails and bases on my machine I clean the mating surfaces with a product I found in a hardware store called "oops" (a fairly strong solvent) and remove the residue of the solvent with isopropyl alchohol. I am very skeptical about using water to clean but I have to admit, the alcohol contains water, so my skepticism may be unwarranted. I'd just be cautious about getting ferrous materials wet.
The problem with solvents is that they can alter the surfaces in ways that might be undesirable.

The issue with water isn't the water per se. It is making sure that everything cleaned is dried properly prior to re-installation and re-use. Just have to be fastidious.
 

am1899

Hall of Fame
#43
In going back and looking at the manual that another member posted, and the pictures you posted, it doesn’t appear there is a way to adjust your bases to fix this issue. I wonder if the bases could be rebuilt with new parts - instead of replacing them outright. But definitely do a thorough cleaning first, if you haven’t already.
 
#44
Edit: this was written immediately following post #39 (by Karma Tennis), but wasn't submitted until ~90 minutes later. Other posts were submitted during this time period.

@KaiserW,

I was just about to ask if you had already tried thoroughly cleaning the rails and the bottoms of both base clamps with 91% isopropyl alcohol?
However, @Karma Tennis has already beaten me to that train of thought.

Since the upper side of the rails directly contact the bottoms of the base clamps, you need to be sure that both surfaces are well cleaned. I mention this because a lot of people will only wipe down the rails, not really thinking that the bottoms of the base clamps would have much of anything on them - but they do.
If you're lucky, this thorough cleaning may just solve your problem (after all, you didn't have this slipping problem 6 weeks ago... or 2-3 months ago, right?)

Also, @10shoe pointed out some key factors... you are putting additional strain on the bases (and actual string clamps too, for that matter) by starting your mains with that method in your video. As @10shoe advised, try tensioning at least 2 mains on one side before beginning to tension a main on the opposite side. By doing this, the clamps/bases have much less strain put on them to maintain things - because the multiple "u-turns", that the string makes through the frame, creates additional friction points that would actually help you out (when you go to apply tension on the other side).
The method you're employing is only giving you one "u-turn" (at the bridge/throat), and that really isn't enough friction points to help counter whatever tension is being applied at the gripper/tensioner.

1. Exactly what tension do you have your machine set at?
2. What kind of string on you using (i.e. is it a very slippery string to begin with)?
3. What gauge is that string (the thinner it is, the easier it is for it to slide around those "u-turns")?
4. Do you have a starting clamp?

If you have a starting clamp, you could use it to help prevent the two clamps from moving toward one another (that is, if you're going to choose to continue using the method in the video).
Here's how...
After tensioning, and clamping, that first string (1MR) you would place the starting clamp on that same string (at the head of the racquet, outside the frame) before you release the string from the gripper/tensioner. Then, when you pulled tension on that second string (1ML) nothing would move.
The two clamps moving towards one another (at 0:54 in the video) is only made possible because the first string (1MR) is able to slide freely through it's grommet at the head of the frame. Placing a starting clamp on that string, outside the frame, would prevent the string from moving through the grommet - and therefore the clamps (and bases) would no longer be able to migrate towards each other (when you then applied tension to 1ML).

Nonetheless, I still think you should adopt a better method of starting your mains, that doesn't create as much undo strain in the first place.

Keep us updated as you work through the various suggestions.
Good luck.
 
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KaiserW

Hall of Fame
#46
That almost looks like there is something missing in the base clamps. The actual base doesn't move linearly, so it is locked in place, but the way it rotates around the central bolt just looks like something is the wrong size or is missing in the body of the base clamp.
I was missing a load bearing in one of the clamps but I got one a put in. Other than that I didn't see anything missing.
 

KaiserW

Hall of Fame
#48
A couple observations:

1. I have never attempted to begin stringing a racquet in this manner. After tensioning the first main on the right side I expected to see you install and tension the second right side main. After this, I would expect you to move over to the left side and install 3 strings in a row. What you are doing puts considerably more strain on the clamp base which has minimal contact with the track at this point in the string job because it is angled across the track. You might even want to consider installing 3 or 4 right side mains before transferring if that is what it takes to get the right side clamp base in maximum contact with the track.

2. I don't have a drop weight machine but listening to all the cranking you are doing is making me wonder how many pounds of tension are you applying?
Thanks will try that. Tension was 54.
 

KaiserW

Hall of Fame
#49
A couple observations:

1. I have never attempted to begin stringing a racquet in this manner. After tensioning the first main on the right side I expected to see you install and tension the second right side main. After this, I would expect you to move over to the left side and install 3 strings in a row. What you are doing puts considerably more strain on the clamp base which has minimal contact with the track at this point in the string job because it is angled across the track. You might even want to consider installing 3 or 4 right side mains before transferring if that is what it takes to get the right side clamp base in maximum contact with the track.

2. I don't have a drop weight machine but listening to all the cranking you are doing is making me wonder how many pounds of tension are you applying?
Thanks will try that. Tension was 54.
@KaiserW,

How did you clean the clamp bases and the rails?

I had a similar issue with a very old machine. Clamp bases would slip at medium to higher tensions (above 50lbs).

I removed clamp bases and rails. Soaked the bases and rails in boiling hot water and strong dishwashing detergent for at least 30 mins. I then scrubbed them using a stiff nylon brush and steel wool. Then heavy wipe with white paper towels. Kept at it with boiling hot water and detergent until no more dark coloured residue on the paper towels.

After this, a proper clean of all components and wipe with Isopropyl alchohol.

Reinstalled everything and no more slippages even up to 65lbs of tension.

I repeat this cleaning process after every 50 restrings.

Also, I start stringing Mains using a Yusuki method with the help of a Starting Clamp and that seems to help a lot.
I cleaned the rails with Isopropyl Alchohol but didn't clean bases. They looked okay but will do them also. I have been starting mains this way for 4 years with no issue but did recently pick up a starting clamp to help with the drawback. I should have used it in the video but it wasn't much better with it.

Hopefully a more thorough cleaning works thanks.
 

KaiserW

Hall of Fame
#50
Edit: this was written immediately following post #39 (by Karma Tennis), but wasn't submitted until ~90 minutes later. Other posts were submitted during this time period.

@KaiserW,

I was just about to ask if you had already tried thoroughly cleaning the rails and the bottoms of both base clamps with 91% isopropyl alcohol?
However, @Karma Tennis has already beaten me to that train of thought.

Since the upper side of the rails directly contact the bottoms of the base clamps, you need to be sure that both surfaces are well cleaned. I mention this because a lot of people will only wipe down the rails, not really thinking that the bottoms of the base clamps would have much of anything on them - but they do.
If you're lucky, this thorough cleaning may just solve your problem (after all, you didn't have this slipping problem 6 weeks ago... or 2-3 months ago, right?)

Also, @10shoe pointed out some key factors... you are putting additional strain on the bases (and actual string clamps too, for that matter) by starting your mains with that method in your video. As @10shoe advised, try tensioning at least 2 mains on one side before beginning to tension a main on the opposite side. By doing this, the clamps/bases have much less strain put on them to maintain things - because the multiple "u-turns", that the string makes through the frame, creates additional friction points that would actually help you out (when you go to apply tension on the other side).
The method you're employing is only giving you one "u-turn" (at the bridge/throat), and that really isn't enough friction points to help counter whatever tension is being applied at the gripper/tensioner.

1. Exactly what tension do you have your machine set at?
2. What kind of string on you using (i.e. is it a very slippery string to begin with)?
3. What gauge is that string (the thinner it is, the easier it is for it to slide around those "u-turns")?
4. Do you have a starting clamp?

If you have a starting clamp, you could use it to help prevent the two clamps from moving toward one another (that is, if you're going to choose to continue using the method in the video).
Here's how...
After tensioning, and clamping, that first string (1MR) you would place the starting clamp on that same string (at the head of the racquet, outside the frame) before you release the string from the gripper/tensioner. Then, when you pulled tension on that second string (1ML) nothing would move.
The two clamps moving towards one another (at 0:54 in the video) is only made possible because the first string (1MR) is able to slide freely through it's grommet at the head of the frame. Placing a starting clamp on that string, outside the frame, would prevent the string from moving through the grommet - and therefore the clamps (and bases) would no longer be able to migrate towards each other (when you then applied tension to 1ML).

Nonetheless, I still think you should adopt a better method of starting your mains, that doesn't create as much undo strain in the first place.

Keep us updated as you work through the various suggestions.
Good luck.
You are exactly right I cleaned the rails but thought the clamp bases were fine. Will clean them this weekend. Yes the slippage only started recently.

I will try starting the mains that way.

Machine is at 54 lbs in video.
It was Alu Power16L but my normal setup is gut/poly.
I just bought a starting clamp. I did try with starting clamp and slippage was not as bad but still pretty bad.
 
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