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Lognic04
22-10-2017, 01:35 PM
Hi all :hi:,
I have noticed that my CGEM's DEC axis is very hard to move - you need to apply about 2 kg of force to get it to move. It definitely isn't binding, i adjusted the gears so that it wouldn't, but the strange thing is, in PHD to move dec it needs about 10-15 pulses, it seems like there is still backlash? :shrug:
I'm thinking that this is stiction caused by the awful grease and/or the ring gear needing to be polished. :question:
:thanx:

Atmos
22-10-2017, 02:24 PM
Is it hard to move while the mount clutches are disengaged?

Lognic04
22-10-2017, 02:40 PM
yes.

multiweb
22-10-2017, 02:45 PM
Sounds like bearings might be binding?

glend
22-10-2017, 03:06 PM
Back off rhe lock nut on the bearing until you can detect play then just snug it ip.

Lognic04
22-10-2017, 03:31 PM
How would i check that?

multiweb
22-10-2017, 07:36 PM
Remove the RA and DEC shafts and check them for scaring. Then make sure the bearings are free and clean and regrease them. I do that to my mount every year.

casstony
22-10-2017, 08:04 PM
Try this for a start, it may be all that's needed.

ChrisV
22-10-2017, 08:59 PM
Even take the lock bolt off.
Also, it could be clagged inside - mine was fairly tight when I got it new at the end of last year. I pulled it apart and re-greased, and it was a lot better.
Another possibility. Could also be that the shaft is bolted on too tightly. Take off the counter-weight-shaft and check down there?

Lognic04
22-10-2017, 09:15 PM
Yeah, I think my mount needs a good regrease. Is it a good idea to get new bearings too or are they not really needed?

ChrisV
22-10-2017, 11:21 PM
I wouldn't bother about things like that yet. Just slowly pull apart and have a look/see. Photograph everything as you go, and watch where each washer was. You need a big bench. You should see pretty quickly what's causing it to be so stuck - if lucky its just the clutch bolt. Try not to force anything. If you get stuck put up photos.

I was lucky I had a CG5 to practice on before I attacked my CGEM

ChrisV
22-10-2017, 11:23 PM
I'm starting to think that might be a good idea - a yearly grease etc

Lognic04
23-10-2017, 06:42 AM
Which lock nut/bearing are you referring to Glen and Chris?

ChrisV
24-10-2017, 01:23 PM
I meant to loosen this clutch knob first and see if it moves OK. If that's tight then its something to do with the shaft and bearings. The whole shaft comes off fairly easily so you can have a looksee. If its out of warranty and you don't mind having a go I can PM how I did it.

If its not that then its probably the worm gear and ring gear (I think that's hat its called) - you said you had loosened the worm gear so there's backlash so its not binding as you say.

Shiraz
24-10-2017, 07:35 PM
Hi Logan - suggest that you try Glen's idea first. I backed off the bearing preload on my (similar) NEQ6 when the dec got too hard to move freely and it worked fine thereafter.

I don't have the mount in question, but think that the nut shown in the very first part of this video is the one to loosen a little bit (after backing off the locking screws as shown) and then gently tighten it back up to the point where side play is gone, but the axis still rotates freely. https://www.youtube.com/watch?v=Cp3Vq_6G5bg The video doesn't show how to get the end cap off to get at the nut, but hopefully that shouldn't be too difficult.