Heq5 Dec backlash

[cuivenion]

Hi, I've recently performed a overhaul of my heq5 mount, regreased the worm mechanism shafts etc. Both the RA and Dec axis were performing fine after the overhaul, no noticeable backlash or other problems. On the the first night out testing it backlash starting creeping in on the Dec axis over the course of the night. It started out with none or very little backlash and ended with a noticeable delay when slewing at 4-8x sidereal. Does anyone have any idea why this would happen?

[Tomatobro]

I found that I had to have several goes at adjusting the backlash before I felt I had it right. Using a dial test indicator I would try to set it at the optimum level for the tightest gear position i could find. Without a DTI its a matter of trial and error to find the sweet spot.

If you did all this during the rebuild then the only thing I can suggest is that something has worked loose.

[cuivenion]

I'll give it another go after I've readjusted then. Just seems strange it would work loose.

[cuivenion]

I think I have an idea on this. I'm using a teflon washer thats a little thicker than the original clear nylon washer so the worm may be slightly misaligned with the worm gear. Obviously I'll need to try different washer thicknesses to see what gets the best results, but is there a good starting point? Say 0.1mm thickness and then go up by 0.1mm a time from there?