Orion Atlas eq-g fine tuning shim issue

[Ali Alhawas]

Hello,

I already did a successful Rowan belt modification myself and it works well, smoother sound and way better autoguiding in PH2.

It worked for almost 5 months without any issue.

Last imaging session the Ra stop moving while slewing to a target, and gives a grounding sound, I stopped every thing and power reset the Mount and the PC , start again and slewing via EQMOD , The Dec. is working well

bur the Ra is giving the same issue.

Back to home and I stripping the Ra axis to check..

I found no issue.. every thing is in place and tight.. So I doubt that the belt or the worm engagement have to readjust again and it seems easy to me as I already done that before.

My only problem is when I calculate the shim to determine what thickness do I need it gives 0.35mm and I assumed this is NO SHIM IS NEEDED, but then I couldn't perform the worm engagement correctly I tried thousands times and It was painful.

I ignored the calculations and add only one 0.5mm shim.. same result..

I decided to add 2 shims 0.5mm each.. then I tried to do the worm engagement! It works !!

Notes :

1- I used ASTRO BABY tutorial for mounts maintenance. 

2- Calculations were repeated many times .. no math errors.

THE QUESTION IS : better to ignore calculations and stick with what works with you.. BUT I am afraid it fails again after a while   

Any recommendations or hints are highly appreciated .

Thanks

Ali.  

Edited December 16, 2021 by Ali Alhawas

[Ali Alhawas]

Update..

Solved !

I found the worm gear wheel was touching the mount case , It made a mark on it all around due to friction ..

I file almost 2mm from the case to make more room for the wheel.. put every thing back together and BANG! It works straight and easy..

That friction didn't make any sound nor feeling stiffness to be observed. Also It was very hard to see it by eyes . My only evidence of the friction is to wipe and clean the wheel and see the friction marks on it .

Hope this help others who struggled like me

CS!