Other CGX adjustments that I have noted/collected here and on youtube can be found as noted:
Hope this helps.
Here is where I discuss the alignment of the motor drive belt system.
Some Suggestions/information I have received from Celestron over time:
Give up trying to guide Declination in both directions until you have mastered guiding Declination in just one direction. A tiny bit of Polar alignment error will create enough Dec drift that you should never need to guide in both directions. There are some very special circumstances where perfect polar alignment is crucial. But in general, if you are getting between 1 and 2 arc seconds of drift in declination per minute, the improvement to your guiding will be worth the penalty paid in field rotation. Unless you have actually observed field rotation in your sub frames, you probably don't need to worry about it.
Remember that no matter what you do with the gear backlash on the worm wheel, a Celestron mount will always show about 60 arcseconds of backlash from the gearbox. This is going to require special handling from your guide software. A properly adjusted CGX-L mount will have between 60 and 150 arc seconds of gear backlash (total). Which means you will need to have 60 to 90 arc seconds of gear backlash from the worm block. Reducing the total amount of gear backlash from 150 arc seconds to just 60 will not eliminate the eliminate the special handling requirement. So don't risk screwing it up just to make this smaller. Always remember, that while your mount is trolling through the gear backlash, a process that will take between 15 and 150 seconds depending on how your guide software handles it, your mount can not guide in Declination in Either directions. If you stop half way through that processes, it will take a comparably long time to exit the gear backlash on either side before guiding can resume. You definitely shouldn't be trying to change directions any more frequently than once per minute. If you find yourself changing back and forth constantly you are probably not guiding at all, just tooling around in the gear backlash.
Do not make RA too tight. Gear backlash does NOT affect RA guiding. Even huge amounts (10 arc minutes) wouldn't matter because the RA tracking motor never stops turning - regardless of the direction you are guiding the mount. Making the RA gear mesh too tight, can cause microbinding which will be hard to see in visually, but will show up as stretched stars in RA.
-------------- Also from Celestron
(with reference to the CGX-L manual 91531_CGX-L_EQ-Mount-and-Tripod_Manual_5lang_Web.pdf)
The mount's behavior could be the cause of the worm gear binding. However, the spring loaded worm block should accommodate this. So it may simply be too tight to where the spring is not recoiling properly.
1. Using a Phillips head screwdriver, remove the gear cover for the axis you intend to adjust (Figure 13).
2. Test the mesh by grabbing hold of the motor and worm block with your hand and pulling it away from the worm wheel. The worm block should recoil slightly, causing the worm gear to back away from the worm wheel slightly.
3. Using a 2mm and 3mm Allen wrench, make very slight adjustments as needed to optimize the gear mesh (Figure 14).
• If the worm block does not recoil, the mesh is too tight, or the limit screw is pushing the block against the worm wheel.
- Turn the Range Limit Screw clockwise and check for recoil.
- Turn the Distance Adjustment Screw clockwise and check for recoil.
• If the worm block recoils but there is noticeable backlash when the axis is locked.
- Turn the Distance Adjustment Screw counterclockwise very slightly, only 1/16th of a turn or less and retest.
- Tighten the Range Limit Screw slightly if the recoil exceeds approximately 1mm.
It’s OK to err on the side of having a little amount of backlash. After the adjustments are made above, try this test before recovering R.A. motor:
Lock down the R.A. axis and gently push against the counterweight shaft in R.A. If they feel a slight “click” in the mount, that is OK, and generally ensures that you will not bind. If you do not feel any movement at all, that should still be OK since they adjusted the mount so that the spring will give, but it still runs a slight risk of binding. Again, side on having a tad of backlash and from that point the spring should accommodate a wide temperature range, eliminating the need to constantly fine-tune the mount.
Daniel, above has a nice collections site of youtube videos .