Simon created a new topic ' Guide calibration fails' in the forum. 3 years ago

Some background. I've previously had trouble with my mount not guiding correctly but about a month ago after taking it apart I noticed the RA axis worm drive was tightened too much. I cleaned, re-greased and made sure everything was tightened correctly. Put it all together and removed any backlash in DEC but didn't bother much with RA as I've heard it's not as important. It worked great after that, I could get around 1"-1.3" RMS guiding pretty consistently. I would have trouble with the calibration failing from time to time as it couldn't move the RA enough but if I retried it would usually work and guiding would be great.

Last night the calibration wouldn't work at all, it would always fail on RA. So I figured the backlash has finally caught up with me and I need to tighten it, which I did. I can barely feel any backlash now, it sounds better and I figured the calibration would be no problem. But it's still causing me problems. I tried again tonight hoping it would be a fluke but it just doesn't work. I was  keeping an eye on the calibration graph tonight and it seemed to me like it would calibrate out but when it came time to calibrate in it would keep going out or perhaps jump around where it was turning around.

I'll give a log from the other night where I did several attempts. I'd love to understand how this is supposed to work, because I would expect that it's trying to move a certain distance out and then in but it'll keep doing moves even if it has seemingly gone far enough out. Keep in mind that sometimes I would touch the mount to see if I could force a movement and get further along in the process but then it could fail on DEC which I never had trouble with.

I would love some help. This feels very discouraging as I'm really looking forward to this season.
It's a Skywatcher NEQ6, rather old but I would say it appears to be in decent condition.
I'm using an Omegon 50/200 guidescope which produces some coma on the stars but I don't think this should be causing trouble.
Then I have the ZWO ASI 120MM-S.

 

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