Celestron COAG helical focuser stuck

[rodrigol]

 

I'm afraid I may have done to damage to my COAG helical focuser. While refocusing my guide camera, I turned the focuser all the way out and it got stuck. I don't want to try to force it as I do feel mechanical resistance and don't want to break it completely. I would appreciate some advice.

Kind regards,

R.

 

Edited February 14, 2023 by rodrigol

[AstroKeith]

Sounds like it might have got cross threaded. Did it come right out, go loose, and you started to wind it back in?

if so, then you must wind it all the way out first. Then try to re engage the threads absolutely square. 

[Peter Drew]

Also, if the helix has a multi-start thread it is slightly more difficult to re-engage and they sometimes have a preferred radial position to restart the engagement.     🙂

[rodrigol]

Thanks for your replies. I will go the obsy and bring in the whole optical train to check your suggestion and answer. 

 

R. 

[rodrigol]

OK. Problem solved. It turns out there are 3 screws holding the focusing ring, which can go loose. You cannot tight them too much or the ring will not turn but rather lock the focuser in place. I have never heard of this issue before with the COAG, but there you go. This OAG is very good but not perfect. 

 

Cheers!