Reversing the Focuser on a Skywatcher 130PDS

[Spaced Out]

Just wondering....... Can I simply reverse my Skywatcher 130PDS focuser ? I mean just by undoing the 4 screws holding the whole focuser unit to the tube, rotating it 180 degrees then screwing it back on to the tube again. Is it that simple or would I need to do focuser collimation of some sort afterwards ?

Thanks.

[Ruud]

Why don't  you just turn the whole scope in its mounting rings?

[Spaced Out]

9 minutes ago, Ruud said:

Why don't  you just turn the whole scope in its mounting rings?

I've fitted an autofocuser and it sticks out the front of the tube. I'd rather it was facing the other way, it would help with routing the wiring.

[Louis D]

You'd probably have to realign/recollimate the focuser (it appears to have collimation screws), but that would be about it.  It appears to have a symmetric base.  Just double check that the focus tube is dead center between the mounting screws in both the X and Y directions.

[Adam J]

33 minutes ago, Spaced Out said:

I've fitted an autofocuser and it sticks out the front of the tube. I'd rather it was facing the other way, it would help with routing the wiring.

You can just remove the pinion and turn it around. Focuser alignment will be maintained. But I would be shocked if the tube rings did not get in the way. I just used mine with the autofocuser focuser out front, did not look great but it worked and that is what matters. 

Edited February 3, 2020 by Adam J

[Spaced Out]

1 minute ago, Adam J said:

You can just remove the pinion and turn it around. Focuser alignment will be maintained. 

Thanks Adam, I tried this but the skywatcher autofocuser seems extremely fickle with tensioning. When I did that I couldn't get it to carry the weight of my camera & filter wheel so I had to put it back again. 😕

I thought this should work too tbh, am I missing something ?

[Spaced Out]

6 hours ago, Adam J said:

You can just remove the pinion and turn it around. Focuser alignment will be maintained. But I would be shocked if the tube rings did not get in the way. I just used mine with the autofocuser focuser out front, did not look great but it worked and that is what matters. 

OK, I've just had another go at reversing the spindle tonight and success !

I mucked about for a while with the tensioning of the focuser. For me there seemed to be a fine line between too loose and too tight when using this skywatcher autofocuser with a heavy camera. Too loose = focuser tube slippage and too tight = autofocuser slippage/clutch.

As you mentioned the tube rings may well get in the way now when I come to balance it, I'll take a look at that tomorrow.

Thanks 👍