Focus motor slipping?

[MacObservatory]

I have a remote setup 1500 miles from me, and don't have a way to check myself. Though there is someone on sight that can fix problems if I know what's going on.

I have a Takahashi TOA-130NFB (4" focuser) and FocusCube 2.

Just shortly after installing this setup and getting things to work. I had a backlash setting of around 220 to achieve a perfect V curve focus routine. On the second night of imaging, I showed a lot more backlash, and had to increase it to 640. By the time I got to the third night of imaging (last night) I've had to set over 1000 steps for backlash to achieve a good V curve, and even shortly after having that set, small amounts of backlash were introduced.

Despite the large backlash numbers, I reliably come to focus in all cases around the 50,000 mark, so despite introducing tons of backlash the focus point seems about the same. This makes me think the set screws that connect the motor to the focuser shaft are loose slightly. And that this is not the draw tube slipping.

Thoughts?

Thanks.

[Evans]

Please check if the motor coupler set screw got loose. This is always the case.