Stuck Gamma Clamp / Clamp Base - Need Advice

estabanj

New User
This week I picked up a Gamma Progression FC ES Electric.


The good news is it has the upgraded quick action base clamps. The bad news is both string clamp / base clamp sets are seized/stuck together. There was surface rust on the base clamp hosels so I assume they are rusted together.
I reached for advice and there was a babolat thread with stuck clamps but that was mostly focused on removing the rust when you get them apart. My challenge is getting them apart without damage.

For the last few days I have been soaking the top and bottom of the hosel with penetration oil (First wd40, then PB Blaster), I have lightly tapped then together and I have used a heat gun (but not too hot) all to no avail.

I have been thinking of ways to apply pulling pressure without damaging them and then I thought of putting them in a bench vice (with padding) and tapping the string clamp out through the bottom of the hosel (of the base clamp) using a metal rod.

My question is - Is this hosel hollow? ie Is the metal I see looking the bottom of the base clamp hosel actually the bottom of the string clamp(see photo below)? So I can tap it out with a metal rod. Or is there a better way?
Thank in advance for any help - Stephen
 

jim e

Legend
I have a different machine, but the base on mine is hollow, as when you take out clamp, you can see right through.
Most likely yours is the same, and it looks like it with the pictures you posted.
I would place a metal bolt a little smaller in diameter to fit on bottom and tap out the clamp.
You machine looks like it sat for a good long time.
You should clean up the rust especially on the rails so the bases slide smooth.
It must have been kept in a damp environment, so I hope the electronics are okay .
 

estabanj

New User
Hi jim e,

Thanks for the response. Yes that is what I suspected. Thanks for confirming.
I think the machine was well looked after until it was given to the person I bought it off. It looks like it sat in his backyard for a while, fortunately it doesn't rain that much in the Bay Area. Not ideal, but I checked that the tension head pulled and didn't stutter, then offered him $50, as I knew the stand was worth more that. I brought it home and it pulled perfectly on tension, didn't even need to calibrate, so I may be lucky.
Yes lots of cleaning, I have restored an Ektelon H and a Neos 1000, but this is my first Gamma.
Cheers
 
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jim e

Legend
Nice that it pulls tension. The remaining thing to do is just clean it up once you get the clamp free. Sounds like you got a great deal. Good for you!
 

Karma Tennis

Hall of Fame
An extreme approach would be to use serious heat - perhaps a portable propane torch - and alternate heating and cooling the clamp stem and the base clamp hosel. Try and set up a process where the expansion and contraction of the two metal surfaces cause them to become loose.

Then use Jim's suggestion to tap out the string clamp using a mallet and a bolt via the bottom of the hosel.
 

estabanj

New User
Hi Karma Tennis,

Thanks for the suggestions. I am a bit reluctant to use a blow torch because of the fiberglass string clamp head and a general approach of taking it slow and doing no harm.

I have been told (and also saw a post) that it required the use of a 12 ton hydraulic press to separate them!

Using Jim e’s method, after days of penetrating oil and using a heat gun I was able remove the clamp by a 1/4 inch but no more. Fortunately this isn’t my main machine so I can take my time but I agree I will eventually need to get more extreme as you say.

Thanks for the suggestions.
Cheers Stephen
 

esgee48

Legend
When you moved the clamp 1/4", did you then try rotating and pulling at same time? You might also try thermal shocking. Cool the metal with an ice cube. Then hit the metal with the heat gun. Then try twisting. If you can turn the clamp in that shaft, you will be 95% there.
 

estabanj

New User
Thanks esgee48

After I got them 1/4, I did try and rotate them, no luck. I did figure that now I had access to the 1/4 inch of string clamp stem then the penetrating oil may work better. So I sprayed them liberally and put them away for a couple of days.

Today I talked to John from Gamma about getting a few small parts and he reassured me that Jim e’s approach was the right way to do it. He did suggest I not use a bench vise, for fear damaging/scratching up the base clamp hosel. He suggested supporting the base clamp between hosel and the quick action lever which I did (see photo). A block of wood 1.5” wide works well. With renewed confidence, and maybe the time leaving the oil do its work, it was pretty easy to tap it them out.

thanks to everyone for their help!

cheers stephen

 
Thanks esgee48

After I got them 1/4, I did try and rotate them, no luck. I did figure that now I had access to the 1/4 inch of string clamp stem then the penetrating oil may work better. So I sprayed them liberally and put them away for a couple of days.

Today I talked to John from Gamma about getting a few small parts and he reassured me that Jim e’s approach was the right way to do it. He did suggest I not use a bench vise, for fear damaging/scratching up the base clamp hosel. He suggested supporting the base clamp between hosel and the quick action lever which I did (see photo). A block of wood 1.5” wide works well. With renewed confidence, and maybe the time leaving the oil do its work, it was pretty easy to tap it them out.

thanks to everyone for their help!

cheers stephen

Glad that you got sorted!

Is John M still with Gamma now do you know or is there a new Gamma Tech?
 
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