Clamps moving a lot

KaiserW

Hall of Fame
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.
Exactly very old and no way to adjust.
 

KaiserW

Hall of Fame
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?
If I start the mains this way do I still double pull and should I have first clamped string on left in beginning and then move to the right?
 

Karma Tennis

Hall of Fame
Thanks will try that. Tension was 54.


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.
Isopropyl Alcohol alone will not clean the metal parts effectively. You really should use detergent and hot water first.

Here's why ...

https://www.quora.com/Is-isopropyl-alcohol-good-for-cleaning-metal
 

10shoe

Professional
Machine is at 54 lbs in video.
It was Alu Power16L but my normal setup is gut/poly.
Can other people with drop weight tensioners please chime in here? Alu Power is a low elongation string and 54 is not an outrageous tension. Is all that ratcheting in the video normal?
 

mmk

Hall of Fame
Did you watch the whole video? The bases are turning on the track.
But as I noted, they aren't moving linearly. Their centers are staying put, which is why I asked if there was something missing, and why Irvin asked if he had added any washers.

OP: did you oil the bases?
 

KaiserW

Hall of Fame
Your clamps are not slipping they are twisting. The clamps and bases are holding but your clamp is twisting on top of the base. Did you ever get in touch with John (@Gamma Tech?)

EDIT: You have not placed any washers anywhere have you?
No washers anywhere, just the thrust bearing that has washer on either side and ball bearings in between.

So in your opinion what would cause that? I did get in touch with John to order replacement parts for inside of clamp base. Load bushing, thrust bearing, and the plastic piece that the bolt goes into secure the clamp bases. Did not make a difference. I have not shown him this video though.
 
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KaiserW

Hall of Fame
But as I noted, they aren't moving linearly. Their centers are staying put, which is why I asked if there was something missing, and why Irvin asked if he had added any washers.

OP: did you oil the bases?
No I didn't oil the bases. Yes it is strange the clamp base is not moving down the line it just seems to me it is swiveling causing my issue. This is driving me nuts.

Strange thing is this only happened recently. I have not done anything different than before.
 

Irvin

Talk Tennis Guru
No washers anywhere, just the thrust bearing that has washer on either side and ball bearings in between.

So in your opinion what would cause that? I did get in touch with John to order replacement parts for inside of clamp base. Load bushing, thrust bearing, and the plastic piece that the bolt goes into secure the clamp bases. Did not make a difference. I have not shown him this video though.
@Gamma Tech see if you can look at the video, the bases and clamps are not slipping, the portion of the base the clamp fits in is twist around the base. Not sure but it looks like the rails are a little lower than the surface of the turntable if that makes any difference or is even possible.
 

Irvin

Talk Tennis Guru
@KaiserW there has got to be something on the bottom of the base that hits the top of the turntable that keeps the bases from twisting. Whatever it is is flat worn out.
 

KaiserW

Hall of Fame
@Gamma Tech see if you can look at the video, the bases and clamps are not slipping, the portion of the base the clamp fits in is twist around the base. Not sure but it looks like the rails are a little lower than the surface of the turntable if that makes any difference or is even possible.
Thanks for your help!

I sent this video to John.
 

KaiserW

Hall of Fame
Back in business guys thanks for all the help everyone!

@mmk and @Irvin you both got me thinking that something was missing or setup wrong in the base. Well it turns out for some reason the thrust bearing was jammed into the knob to tighten the base clamp instead of sitting in it. I never have opened the base clamps before so not sure how it didn't cause me an issue until now.

@10shoe I tried your suggestion of tensioning 3 mains before moving to the other side. I think that also helped.

I still have a little slippage but nowhere near like in the video. I will do a more thorough cleaning soon.

Thanks again everyone! This forum is fantastic!
 

chrisb

Semi-Pro
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.
Try alcohol with tooth brush If no than consider floating clamps the best are the metal stringway clamps
 

Gamma Tech

Professional
In my previous response I mentioned tightening the 17mm lock nut to adjust the base clamp, however after seeing your video you have a very early model Progression machine. The base clamps on that machine have been out of production for several years and the base clamps are no longer available. However the locking mechanism parts for the clamp are still available and it can be rebuilt. Another option is that the turntable on your machine will accept the current model base clamps. The Gamma MQAC-11 base clamp will fit that machine.
 

KaiserW

Hall of Fame
In my previous response I mentioned tightening the 17mm lock nut to adjust the base clamp, however after seeing your video you have a very early model Progression machine. The base clamps on that machine have been out of production for several years and the base clamps are no longer available. However the locking mechanism parts for the clamp are still available and it can be rebuilt. Another option is that the turntable on your machine will accept the current model base clamps. The Gamma MQAC-11 base clamp will fit that machine.
How much are the Gamma MQAC-11 base clamps and does it come with the clamp itself?
 

dhnels

New User
With all respect to John, I'm not sure those clamps will fit your rails. Your rails look really thick in the video. I have a set of those MQAC-11 base clamps (maybe for sale) from an older turntable and the rails were 8.5-9mm thick with a 14mm wide slot. What are those measurements for your rails?
 

KaiserW

Hall of Fame
With all respect to John, I'm not sure those clamps will fit your rails. Your rails look really thick in the video. I have a set of those MQAC-11 base clamps (maybe for sale) from an older turntable and the rails were 8.5-9mm thick with a 14mm wide slot. What are those measurements for your rails?
The slot is 3/4" wide or 19mm.
 

KaiserW

Hall of Fame
Ugh so I am not out of the woods yet. When I said everything was good I was stringing poly. Last night I did gut/poly and I was seeing some pretty bad movement again on the mains. I guess gut is more prone to this.

I may just pick up some floating clamps for now until I decide if I want to invest in another machine.
 

Wes

Semi-Pro
I 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.
I just bought a starting clamp. I did try with starting clamp and slippage was not as bad but still pretty bad.
This is driving me nuts.
Back in business guys thanks for all the help everyone!

@mmk and @IrvinI tried your suggestion of tensioning 3 mains before moving to the other side. I think that also helped.

I still have a little slippage but nowhere near like in the video.
Ugh so I am not out of the woods yet. When I said everything was good I was stringing poly. Last night I did gut/poly and I was seeing some pretty bad movement again on the mains.

I may just pick up some floating clamps for now until I decide if I want to invest in another machine.
I'm having a hard time understanding exactly how you're still having the problem.
You claim that, despite utilizing the starting clamp (AND tensioning a couple of mains on one side, before tensioning any on the oppostie side) that you're still having things moving/twisting around.

Did you actually try the procedure (to the letter) that I suggested?
Again, I can't understand how the problem can persist when using the starting clamp in the manner I've outlined below.

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).
It should be physically impossible for the clamps to continue to move toward one another, because the string can no longer migrate through the grommet at the head end of the frame (that is... unless your starting clamp has string slipping through it TOO).

Post a video showing the slipping/twisting, using the method I've outlined.
I've got to see this with my own eyes.
 

KaiserW

Hall of Fame
I'm having a hard time understanding exactly how you're still having the problem.
You claim that, despite utilizing the starting clamp (AND tensioning a couple of mains on one side, before tensioning any on the oppostie side) that you're still having things moving/twisting around.

Did you actually try the procedure (to the letter) that I suggested?
Again, I can't understand how the problem can persist when using the starting clamp in the manner I've outlined below.



It should be physically impossible for the clamps to continue to move toward one another, because the string can no longer migrate through the grommet at the head end of the frame (that is... unless your starting clamp has string slipping through it TOO).

Post a video showing the slipping/twisting, using the method I've outlined.
I've got to see this with my own eyes.
I will post another video probably tomorrow.
 

Karma Tennis

Hall of Fame
@KaiserW, @Wes,

Are these possibilities? ...

1/ The turntable if warping under pressure. This is reducing the friction between the clamp bases and the tracks because they are no longer flush against each other. Reduced friction means reduced grip so the clamp bases slip more easily.

2/ The tracks themselves are not mounted securely enough to the turntable so they are lifting or moving enough to compromise the grip between the clamp base and the track.
 

KaiserW

Hall of Fame
@KaiserW, @Wes,

Are these possibilities? ...

1/ The turntable if warping under pressure. This is reducing the friction between the clamp bases and the tracks because they are no longer flush against each other. Reduced friction means reduced grip so the clamp bases slip more easily.

2/ The tracks themselves are not mounted securely enough to the turntable so they are lifting or moving enough to compromise the grip between the clamp base and the track.
Not sure about 1. The rails are mounted well I see no issue there.
 

10shoe

Professional
The reason I asked someone with a dropweight machine to weigh in here on the amount of tensioning you are doing (there's a lot of ratcheting in the video) is that from what I can see, the clamp base on the right side is holding fine. It is doing its job on the first tensioned string. But then you switch over to the other side and I hear all this ratcheting and now all of a sudden not only is the left clamp base not holding, but the right clamp base is turning. Given enough pressure, any clamp base will do this. So, the question I am having is: What is going on there with the drop weight? Are you leaning on it? You are tensioning a poly with very little elongation at a modest 54 lbs. Drop weight movement should be minimal and yet.......
 
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KaiserW

Hall of Fame
The reason I asked someone with a dropweight machine to weigh in here on the amount of tensioning you are doing (there's a lot of ratcheting in the video) is that from what I can see, the clamp base on the right side is holding fine. It is doing its job on the first tensioned string. But then you switch over to the other side and I hear all this ratcheting and now all of a sudden not only is the left clamp base not holding, but the right clamp base is turning. Given enough pressure, any clamp base will do this. So, the question I am having is: What is going on there with the drop weight? Are you leaning on it? You are tensioning a poly with very little elongation at a modest 54 lbs. Drop weight movement should be minimal and yet.......
Hmm not doing anything different than in the past with the drop weight. Pretty normal imo as all the string in the beginning needs to tighten around the drum. So the first several mains will have more racheting the than outer mains.
 
C

Chadillac

Guest
Here is a new video.

I think you should get a new stringer (if you have cash). Your machine makes you work alot more, should be like two drops (drop weight or one button on elec) if you got rid of the ratchet thing and those clamps must keep your forearms in shape :)

The swivel base thing on clamp to stringer is really fast. Can adjust easy, both sides, with an allen wrench.

You can also pull the slack out with your hand before putting in tensioner, was alot of cranking

The six mains (when measured) should only take like 1min. Your pull through is nice but so much extra time spent
 

NuBas

Legend
Have not read thread but is it normal for multifilament to slip, I have to clamp it much much harder than stringing poly.
 

Karma Tennis

Hall of Fame
Here is a new video.
@KaiserW,

It appears form your latest video that the clamp bases are not completely flush with the turntable. Look at your video at 2min 19sec. There appears to be a small gap between the clamp base and the turntable. Only a small area of the clamp base is making contact with with the turntable and that contact only appears to be with the silver rails. So there does not appear to be as much clamping friction force as their could be.

Also, the clamp bases are quite long. The distance between the actual clamp base bold and the clamp stalk is quite large. This distance creates quite a bit of leveraging force which will conspire to overcome the friction required to keep the clamp base in position.

Both of those things might be contributing to your problem.
 

KaiserW

Hall of Fame
I think you should get a new stringer (if you have cash). Your machine makes you work alot more, should be like two drops (drop weight or one button on elec) if you got rid of the ratchet thing and those clamps must keep your forearms in shape :)

The swivel base thing on clamp to stringer is really fast. Can adjust easy, both sides, with an allen wrench.

You can also pull the slack out with your hand before putting in tensioner, was alot of cranking

The six mains (when measured) should only take like 1min. Your pull through is nice but so much extra time spent
I am really considering buying a new machine. Have gotten my money's worth out of this one.
 

KaiserW

Hall of Fame
@KaiserW,

It appears form your latest video that the clamp bases are not completely flush with the turntable. Look at your video at 2min 19sec. There appears to be a small gap between the clamp base and the turntable. Only a small area of the clamp base is making contact with with the turntable and that contact only appears to be with the silver rails. So there does not appear to be as much clamping friction force as their could be.

Also, the clamp bases are quite long. The distance between the actual clamp base bold and the clamp stalk is quite large. This distance creates quite a bit of leveraging force which will conspire to overcome the friction required to keep the clamp base in position.

Both of those things might be contributing to your problem.
Yes there is some give in my clamps, when I tighten I try to make as flushas possible. I wonder if the thrust bearing is setup correctly in the base. Have been trying to find a diagram of this but no luck.

I will post a video of the bushing setup later today. Maybe I have the bushing in wrong.
 

Karma Tennis

Hall of Fame
Yes there is some give in my clamps, when I tighten I try to make as flushas possible. I wonder if the thrust bearing is setup correctly in the base. Have been trying to find a diagram of this but no luck.
Does the clamp base move when the string clamp is in a direct line with the tensioner and you pull tension? (IE Does the base slide along the rail towards the tensioner? If it does then either the clamp base is the problem or the track is too slippery. If it holds tight then I think it is likely to be something I suggested in my prev. post.

(Alternatively, rotate the turntable 90 Degrees, lock the clamp base down at right angles to the rail so that the clamp base is in line with tensioner and pull tension.)
 

Irvin

Talk Tennis Guru
Here is a new video.

Does not look good. If you sent it to Gamma / Tennis Machines to have it repaired shipping both ways will cost more than the machine is worth. I’d get a new machine. It looks to me like the clamps, bases, gripper, and racket are all worn out. Fixing everything would not be worth it.
 

KaiserW

Hall of Fame
Does not look good. If you sent it to Gamma / Tennis Machines to have it repaired shipping both ways will cost more than the machine is worth. I’d get a new machine. It looks to me like the clamps, bases, gripper, and racket are all worn out. Fixing everything would not be worth it.
I am leaning that way. My birthday is in July so would be an early present to myself!

Still would like to get my machine functioning better though so I could sell it. Current state I would not sell unless I am up front about the slippage issue to the buyer. I am not the most mechanical person as you guys can probably tell.
 

10shoe

Professional
These screw type clamp bases leave a lot to be desired and if you can't repair them or upgrade them then buying a new machine with better bases sounds good to me. But I am looking forward to your next video. I expect the design of these clamp bases is extremely simple and I am thinking we will see something that can be remedied with inexpensive and readily available materials.

That said, you keep doing surprising things in your videos. In your first video, stringing 1LM immediately after 1RM caught me by surprise. In this video, you released the starting clamp after releasing the tensioner instead of before. This is something I would not do and to a certain extent, the violence of it is causing the clamp base to move. Had you removed the starting clamp while holding tension, and gently released tension thereafter, I think the base would still have moved but I think considerably less.
 

KaiserW

Hall of Fame
These screw type clamp bases leave a lot to be desired and if you can't repair them or upgrade them then buying a new machine with better bases sounds good to me. But I am looking forward to your next video. I expect the design of these clamp bases is extremely simple and I am thinking we will see something that can be remedied with inexpensive and readily available materials.

That said, you keep doing surprising things in your videos. In your first video, stringing 1LM immediately after 1RM caught me by surprise. In this video, you released the starting clamp after releasing the tensioner instead of before. This is something I would not do and to a certain extent, the violence of it is causing the clamp base to move. Had you removed the starting clamp while holding tension, and gently released tension thereafter, I think the base would still have moved but I think considerably less.
Good point on the starting clamp. Just watched my video again and realized I did that, the base slid a decent amount after I released it.

Yes I will post a video on the insides of the base clamps.
 

10shoe

Professional
I don't think the bearing is an issue. It's just there to make turning the knob smoother.

What I was hoping to see was the underside of the clamp base. Is it metal? And is there any way to improve its grabbing power?
 

KaiserW

Hall of Fame
I don't think the bearing is an issue. It's just there to make turning the knob smoother.

What I was hoping to see was the underside of the clamp base. Is it metal? And is there any way to improve its grabbing power?
On the left in the video you can see the parts. The part the base handle screws into is metal but the guide and load bushing is plastic.

I don't see how to improve grabbing power, I pretty tighten the handle as tight as it will go.
 

KaiserW

Hall of Fame
Does the clamp base move when the string clamp is in a direct line with the tensioner and you pull tension? (IE Does the base slide along the rail towards the tensioner? If it does then either the clamp base is the problem or the track is too slippery. If it holds tight then I think it is likely to be something I suggested in my prev. post.

(Alternatively, rotate the turntable 90 Degrees, lock the clamp base down at right angles to the rail so that the clamp base is in line with tensioner and pull tension.)
The base clamps seem to slide away from tension head in most cases. Excessive drawback imo.
 

10shoe

Professional
On the left in the video you can see the parts. The part the base handle screws into is metal but the guide and load bushing is plastic.

I don't see how to improve grabbing power, I pretty tighten the handle as tight as it will go.
You're not reading me as intended. When I say grabbing power I'm referring to the surfaces of the track and the bottom of the clamp base and how well they grab each other. The bottoms of my clamp bases are metal. I clean them periodically with a solvent called "oops". I clean the tracks with the same solvent. This is usually sufficient to control any slippage problems.

But what are the bottoms of your clamp bases made of?
 
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KaiserW

Hall of Fame
You're not reading me as intended. When I say grabbing power I'm referring to the surfaces of the track and the bottom of the clamp base and how well they grab each other. The bottoms of my clamp bases are metal. I clean them periodically with a solvent called "oops". I clean the tracks with the same solvent. This is usually sufficient to control any slippage problems.

But what are the bottoms of your clamp bases made of?
The bottoms are metal. I will clean again maybe I didn't do a good enough job. Thanks
 

Karma Tennis

Hall of Fame
The base clamps seem to slide away from tension head in most cases. Excessive drawback imo.
If I understand you correctly, that doesn't make sense and actually defies the laws of Physics.

How can the clamp base slide AWAY from the tension-head if you are pulling tension? It must either slide towards the tension head (if it is slipping) or remain in the same place (if it is gripping properly).
 

KaiserW

Hall of Fame
If I understand you correctly, that doesn't make sense and actually defies the laws of Physics.

How can the clamp base slide AWAY from the tension-head if you are pulling tension? It must either slide towards the tension head (if it is slipping) or remain in the same place (if it is gripping properly).
Sorry meant to add when releasing tension. That is when I see the most movement.

When pulling tension movement is very minimal.
 

10shoe

Professional
The bottoms are metal. I will clean again maybe I didn't do a good enough job. Thanks
These clamp bases of yours are about as rudimentary as it can get. As long as the bottoms of the base and the track are clean, and you haven't stripped the threads of the bolt extending from the knobs, they should hold.

Now, if they don't, one drastic measure I suppose you could try would be to sandpaper the base bottoms (or perhaps the track). I have never done this. But I have done the equivalent with the glide bars on an Ektelon H. If you were going to do this, I think you would want to sand in a straight line, going the long way. I am sure Gamma would NOT approve, Ektelon definitely did not. I didn't let that stop me and in my case it helped.
 
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KaiserW

Hall of Fame
These clamp bases of yours are about as rudimentary as it can get. As long as the bottoms of the base and the track are clean, and you haven't stripped the threads of the bolt extending from the knobs, they should hold.

Now, if they don't, one drastic measure I suppose you could try would be to sandpaper the base bottoms. I have never done this. But I have done the equivalent with the glide bars on an Ektelon H. If you were going to do this, I think you would want to sand in a straight line, going the long way. I am sure Gamma would NOT approve, Ektelon definitely did not. I didn't let that stop me and in my case it helped.
After I do another cleaning, if I still get slippage I might as well try it. Thanks
 
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