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CGEM - Play in the RA Axis

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4 replies to this topic

#1 drksky

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Posted 22 February 2013 - 11:53 AM

I recently purchased a used, hyper-tuned CGEM that while tracks well and is very smooth, has a lot of play in the RA axis. What can I do to eliminate this play? Does the worm need adjusted? Any guides for doing that on a CGEM?

#2 DaveJ

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Posted 22 February 2013 - 12:14 PM

...What can I do to eliminate this play? Does the worm need adjusted? Any guides for doing that on a CGEM?


Here you go - worm/wormgear adjustments. These instructions are specifically for an Atlas/EQ6, but the method for the CGEM is identical.

#3 Raginar

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Posted 22 February 2013 - 03:34 PM

Tony, go to the CGEM yahoo group. There is specific instructions on adjusting the CGEM worm on there. It is similar, but I like seeing the CGEM info :).

I can't remember how much play my CGEM had... did you try just balancing it heavy to the meridian you're imaging in?

#4 drksky

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Posted 22 February 2013 - 03:54 PM

I wasn't really doing any imaging. I had my LS80 on it and the image was jumping out of the FOV while I was trying to adjust the tuning. I can grab the CW shaft and wiggle it more than I think I should.

#5 John O'Grady

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Posted 22 February 2013 - 10:04 PM

I had similar play in the RA on my CGEM that I resolved by adjusting the worm gear. Mount has performed much better since making the adjustment.

Fortunately your mounts already been hypertuned. For those reading this that have a CGEM and want to adjust the worm gear, read this warning caution from Ed Thomas (happened to me):
http://tech.groups.y...EM/message/7756

Unfortunately I found Ed's post after performing the worm gear adjustment. Live and learn.


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