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Smokedaddy
02-29-2008, 10:51 PM
Well, here is a new one...

Below is a link to a rare 6" Goto telescope counterweight shaft and the weights. The fellow screwed on the counterweight, then another, they mated up snuggly but neither will move, they have locked together. He can't get them apart. He tried to turn them up the shaft, down, nothing. He and a friend have tried to turn them separately in different directions...nothing. He bought a strap wrench to move them...nothing.

http://www.pbase.com/smokedaddy/image/93587468

Any suggetions,
-SD:

mochinist
02-29-2008, 10:58 PM
So I guess he cant unscrew them totally off the screw?


Try heat

Smokedaddy
02-29-2008, 11:03 PM
That's the way I understand it. Personally, I wonder what caused this in the first place?

-SD:

mochinist
02-29-2008, 11:07 PM
That's the way I understand it. Personally, I wonder what caused this in the first place?

-SD:kinda like a lock nut if you are familiar with that

dp
02-29-2008, 11:14 PM
Someone probably spilled a softdrink on it and they're sugared together. I think I'd try a boiling hot dip and soak.

mechanicalmagic
02-29-2008, 11:34 PM
Using soft aluminum or copper sheet to soften the jaws, grab the first disk in a four jaw chuck, (either end doesn't matter, I assume the counter weight shaft can be removed).

Try the strap wrench.

If that doesn't work, again using Al or Cu, grab the far counterweight with another four jaw chuck, (if you have one), or a three jaw.
Twist.

Next level is destructive.
Dave

Smokedaddy
02-29-2008, 11:35 PM
Yea, I understand the lock nut concept, I figured it had something to do with the way the threads were cut and how flat the faces were machined on the counterweights themselves.

-SD:

lenord
02-29-2008, 11:38 PM
SD

I had a similar problem on a Tak mount. Here is what worked quickly for me.

Drill a shallow, ~1" deep x 1/4" diam. hole, in the sides of each of the CW, in a straight line, parallel to the CW shaft. Plug the holes with a 2" long x 1/4" diam. pieces of drill rod. Put a piece of something between 2 of the posts and twist them apart.
Should take 5 minutes with a good sharp 1/4" drill bit.

Lenord

wierdscience
02-29-2008, 11:59 PM
Stick them in the freezer.I am guessing he might have screwed the whole mess together when they were cold(like on a clear winter night perfect for start gazing)and when they warmed up they stuck.

juergenwt
03-01-2008, 01:52 AM
Drill a shallow hole in each dick and use a punch.Hold the part in a chuck or vise and just tap it to unscrew.

Your Old Dog
03-01-2008, 07:42 AM
Check out my post on similar thread.

http://bbs.homeshopmachinist.net/showthread.php?t=27854&highlight=lead

You might also try boring an aluminum plate the thickness of one of those disk, clamp it on the disk and then slap it with a BFH.

Could also drill a small hole for a spanner wrench in side of each weight to aide in getting them off in the future.