zero backlash neq6 worm

[Mike M]

6 hours ago, mbalkham said:

You've got to change your scale to 4" or even 2"! Looks super smooth though. I think the weight on mine is pushing me to look at a mount upgrade. Better start saving the $$$!

Yeah I think because my F5 is so long and heavy, it's still floating the worm spring a bit even with the zero backlash worm mod.. I'm definitely not meant to be carrying a 10" that's for sure.  I'll make it slightly east heavy tonight and try 2-4 seconds again - with it 2-4 seconds before the guide star was leaving trails sometimes still.  With 1 second it was counteracting the oscillations. 1.9 Arcseconds of seeing tonight should help too compared to 4 last night. 

Cheers

[Merlin66]

Not sure about the “spring” reference. I haven’t seen one on an NEQ6PRO mount.

 

[mbalkham]

35 minutes ago, Merlin66 said:

Not sure about the “spring” reference. I haven’t seen one on an NEQ6PRO mount.

 

This zero backlash mod mounts the worm gear on a 'spring' to keep contact without east heavy balance. 

[Merlin66]

Ahhhh, sorry.

I should have read the thread from the beginning.

 

[Mike M]

So I had still been fighting with the mount since the upgrade so tonight pulled it apart again and found that 14 of the 16 screws that secure the 4 tension Springs were completely loose. I didn't even think to check them from the factory and there was nothing in the instructions about checking them.. here's a pic showing one spring undone about 3 threads. Guiding now is great and the Ra is Rock solid.

Cheers, Mike

Edited June 24, 2020 by Mike M

[Mike M]

Here's a preview so far of my current target, this is 58x300s luminance at gain 0, -10c.. we had a decent breeze last night and the mount performed perfectly! 100% crop with no darks or flats at all, just a quick stretch with curves and levels.  

 

[Mike M]

Hi all, finally finished the image - here's the results of the upgrade, everything looks good and the mount is behaving perfectly.  Can't complain with how it's all looking now  - https://www.astrobin.com/full/2ttqs5/0/?real=&mod=

[mbalkham]

10 minutes ago, Mike M said:

Hi all, finally finished the image - here's the results of the upgrade, everything looks good and the mount is behaving perfectly.  Can't complain with how it's all looking now  - https://www.astrobin.com/full/2ttqs5/0/?real=&mod=

Nice work Mike. Clouds for 2 weeks here so haven't been able to test my latest tweeks, maybe this weekend. My Goldfocus has turned up to help tripple check my colimation (also use glatter and catseye!).   

[mbalkham]

Struggling tonight on RA. Still think this is a setup issue. RA is normally half this error. Any ideas?

[bottletopburly]

My guiding usually a bit like yours shown , thinking maybe it was the mount , then last session on the eagle nebula I guided at 0.30RMS ,Graphs was near flat  exposure I had down to something like 1sec usually I was using 2-3sec maybe it was a combination of things being right seeing on the night was very good , maybe on the night conditions weren’t favourable for you , I use the predictive Pec algorithm on my Eq6 belt mod mount .

[david_taurus83]

23 minutes ago, mbalkham said:

Struggling tonight on RA. Still think this is a setup issue. RA is normally half this error. Any ideas?

What guide setup are you using?

[mbalkham]

Think I might have sorted it. RA belt needed a bit of tension. I also rebalanced. Guiding back to 0.8-0.9 RMS.

[mbalkham]

Finally got everything working how it should. Re-tweeked gear meshing, re-distributed weight on OTA and improved balance. Now running the NEQ6 at 0.3-0.5" RMS with over 20kg OTA and 20kg counterweight. ZWO OAG also helping i think.