Celestron c gem mount re greasing

[todd8137]

Hi all well I got this mount a while ago used it a couple a times due to bad wether ,mounted it on the pier .i noticed that the white grease as gone very cakes almost like chalk ,it came like this .so the bearing is dry and I need to grease it up when I take the weight bar of it exposes one of the bearings ,it's the other bearing I can not see and can not grease

As any one else greased these bearings ect on a cgem ? I do not fancy stripping the head down ,no knowledge of his sort of thing so if any one can point me in the right direction. All help would be great

Pat

[x6gas]

Are you talking about the taper bearings?

I'm guessing so. It seems that some of the CGEMs (mine and at least two other SGLers) have the retaining rings on the taper bearings way too tight. Some of the roller bearings making up the taper bearing on mine were seized because it was so tight.

It's a massively simple job so long as you have the right tools...

DEC:

1. Take off the counterweight bar
   
2. Remove the counterweight nut (the thing that the counterweight bar screws in to)
   
3. There is an aluminium retaining ring holding the taper bearing on the axis. It is secured against the axis with two grub screws 1.5mm allen key needed, loosen them off by a turn or so. Their is a hole in the housing and you need to rotate the DEC axis to align the gubs screw with the hole so that you can use the allen key to slacked off the grub screws... The retaining ring has two holes and you can use a good quality pair of circlip pliers to loosen the retaining ring by half a turn. Basically it only needs to be nipped up to hold the taper bearing up - I have no idea why they overtighten it! Hand tight is fine. Tighten up the grub screws and you are done on the DEC axis.
   
4. If the taper bearing is dry, then remove the retaining ring completely, drop the taper bearing off of the axis and regrease it by pushing your favourtite grease (I use a lithium based grease with WS2) into the bearing. Refit and screw the retaining ring hand tight as above...
   

RA:

1. Pretty much as above.
   
2. Remove the polar scope if you have one.
   
3. Remove the orange anodised facia - three cross head screws
   
4. Slacken off the four 2mm allen grub screws on the aluminium retaining ring
   
5. Back the retaining ring off by half a turn and retighten grub screws
   

If the RA bearing is dry, follow the process outlined for DEC.

Both the RA and DEC axis should be pretty free when the clutches are released. With the counterweight bar attached (but no actual weight) the RA axis should freely swing five or six times (like this:

). This has nothing to do with worm gear meshing or anything else. If it does not swing freely then it is either the worm mechanism binding on the mount body or - much more likely - an overly tight taper bearing.

HTH.

[ronaldo999]

you tend to find the grease on any mount does not take long to start going hard, maybe something to do with temps. if you can strip down just replace with a good quality grease that covers the temp range.

[todd8137]

you tend to find the grease on any mount does not take long to start going hard, maybe something to do with temps. if you can strip down just replace with a good quality grease that covers the temp range.

Thanks the old grease was like chalk very Carey regressed but not tried the above yet will give it ago later maybe

[ronaldo999]

there are some good guides online regarding stripping down the CG5 mount and this gives ideas of the best grease to use i believe

[x6gas]

there are some good guides online regarding stripping down the CG5 mount and this gives ideas of the best grease to use i believe

I can recommend http://reelschematic.com/isc/products/BadFish-Barracuda-Grease.html

[billhinge]

Can't go wrong with bad fish (not really grease but ws2 in oil - you can get pure powder as well)

[todd8137]

All sorted now old tnread