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G11 Dec Axis Clutch Trouble? Or....?

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#1 Cotts

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Posted 04 April 2009 - 11:17 AM

First a question: when the scope is moved in declination should the ENTIRE polar axis shaft, including the counterweights, rotate?

Now the perceived problem. When I loosen the RA clamp all the way the mount 'freewheels' with very little friction. A tiny finger push will cause the mount to glide easily. This is decidedly not the case with the DEC axis. No matter how much I loosen the clutch the rotation remains stiff. It takes two hands to rotate it. Is my DEC clamp 'stuck'? And if so, is there a fix for the problem that I can do myself? Thanks for the help. d.c.

#2 Fordracer1

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Posted 04 April 2009 - 10:48 PM

David,

Yes, the entire dec shaft including counterweights and counterweight shaft should rotate when you move the mount in declination - at least mine does.

Something must be going on with your RA axis because both axes should move VERY easily with the clutches loosened. One question however - are you trying to rotate the mount in RA with a scope or scopes mounted and properly balanced? If you had a fairly heavy counterweight relatively far down the CW shaft but no scope mounted and tried to rotate in RA with the CW shaft straight down it would seem to be difficult to move, however if you were to rotate the RA axis just a little so the CW shaft was no longer straight down it should easily rotate back to the CW shaft down position. Be careful doing any of this without a mounted and properly balanced scope as the CW shaft will rotate down rather quickly if you have one or more counterweights mounted and the RA axis is working correctly.

The bottom line is that either axis should rotate easily with the clutch on that axis loosened if everything is balanced correctly and working correctly. Hope this helps!

#3 Cotts

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Posted 05 April 2009 - 08:00 AM

Hi, John. Thanks for the info. You are right about the balancing issue but fear not - I have the thing balanced nicely. It seems that the Dec clutch is stuck on. Now I have to find out how to 'unstick' it. I'll have a look in the Losmandy Yahoo forum as well as await anything here on CN. I need to clear this up before the Gemini system arrives later this month. Cheers, d.c.

#4 Kaizu

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Posted 05 April 2009 - 12:10 PM

I recommend to check the needle bearings between the shaft and the dec worm wheel. When the cluth is tight, it connects the shaft to the worm wheel and when it's loosen, the shaft rotates on the needle bearings.

Kaizu






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