Here's a video of my mount post surgery. I've replaced the gearboxes by McLennan equivalents. They have a steel front and backing rigidly fastened by four rods that go through the casing. Only the side casing is covered in plastic but it's not structural. The shaft is a little smaller in diameter, they rotate the other way around also so you need to set the mount to custom in the Gemini settings. The motor pinion also has more teeth and is a little wider but the gear ratio ends up being the same.
The main advantage is that the motors mounting is solid and much stiffer. There's also close to zero backlash compared to my old gearboxes but that might well be wear on the old plastic ones.
In RA I've obviously put the smoothest worm assembly and quietest motor. The DEC motor is a little noisier than the RA. But that's the motor only, nothing to do with the transmission. You can hear the difference in noise level between RA and DEC in the video.
Sometime it sounds a little louder but it's the camera auto noise level that ramps up the sound level when it's too quiet. Anyway it sounds pretty good so far. There's no vibration transmitted to the worm. I think the oldham coupler helps here but these gearboxes run smoother as well.
There's a couple of things I'm still working on. New thrust bearings for RA and DEC, new high precision bearings fro RA worm, new pinions for the DEC motor and also some new bushes for the couplings. This is all to minimize axial offset in the transmission train.
When the clouds are gone I'll get out and do some PE see how that pans out as is and get some measurements.
