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OK Who's Happy With Their CGEM

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#51 airydisc


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Posted 13 June 2009 - 02:23 PM

Just got it last night. I have to admit that it looks very impressive, but I was immediately troubled by the amount of slop (or play) in both RA and DEC axes. I haven't measured it (clouded over last night) but I'm guessing it's at least an arcminute. Is this normal? How do you adjust the worm gear mesh? I don't see anything about it in the manual.


#52 waassaabee


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Posted 14 June 2009 - 08:51 AM

Greg, That doesn't sound right... My CGEM has no slop at all, but I believe there are backlash settings you can adjust in the hand controller. But if it bothers you (and it would me), I'd be on the horn to Celestron.

#53 Doug6952



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Posted 14 June 2009 - 09:58 AM

To adjust the worm mesh:

Loosen the 4 bolts that hold that axis down.
there are 2 set screws that need to be adjusted on each axis. The one closest to the motors/worm (there are round black covers on the outside) if you turn this in it loosens the gear mesh and turning it out will tighten. The other set screw (180° from the first) has the reverse effect (DO NOT over tighten this set screw)

After adjustment is done. tighten the 4 bolts.

#54 airydisc


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Posted 14 June 2009 - 10:26 AM

Thanks, guys. I've e-mailed Celestron and will try to contact them Monday. I'm comfortable with making the adjustment, but want to make sure it doesn't void the warranty, since the manual doesn't say anything about it. My Losmandy mount describes the procedure in detail, understanding that it is essential to proper operation of the mount.


#55 chollman


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Posted 14 June 2009 - 02:48 PM

I love the CGEM. Have had it for a few weeks now. It takes a few times out to learn but I am happy to say it gets better every time out. The polar alignment is excellent. This mount tracks perfectly. Also "trained" the mount for the tube to not hit the legs, as I use an 8" f/8 newt. This also works perfectly. I also switched out the tubing legs for shorter, heavier ones from the local hardware store. Celestron has made this easy to do with 4 set screws. Kudos to Celestron for making such a good mount affordable...Charlie

#56 PhilCo126



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Posted 22 June 2009 - 04:46 AM

Looks like most of us are happy with the CGEM, but who replaced some "plastic" parts with ADMaccessoires and are these worth the "little" investment?

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