Focus motor kit excessive backlash

[Mnorman]

I just purchased and installed a Focus motor kit which I’m using an Ultimate Powerbox V2 to control. The installation was fine and hardware and software work, but the backlash seems excessive, so much so that this is not a usable autofocus solution.

By simple visual inspection, the backlash exceeds 400 steps. No pinion shaft movement is evident on a direction change after twice selecting a 200 step move in the focus tab of the app. Once the backlash is cleared (on a third 200 step move), movement is immediately evident.

I have been unable to get an autofocus routine to work in NINA whether I use backlash compensation in the UPBV2 controller or not and whether I use backlash compensation in either absolute or overshoot modes in NINA, with settings ranging from 400-600 steps.

I can manually focus by approaching the focus point from one direction, but this is not a workable solution for imaging.

It would seem to me that trying to achieve a reliable optimal focus within 15-25 steps when there are 400+ steps of backlash is more than can be expected from any backlash compensation algorithm.

Is my Focus Motor Kit out of spec, in which case, could I please get a warranty replacement?

Please let me know what to do.

I use Pegasus products extensively and am impressed by their functionality and build quality. I’m hoping the Focus Motor Kit will live up to my experience with your other products.

Thanks,

Michael Norman

[Mnorman]

Ok Evan politely pointed out that it was likely that I hadn’t tightened the coupling set screws enough. Turns out that despite my checking this (more than once, I thought), it appears he was right.

Think everything is in order now.