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Reversing the focusing axis L/R? (1 Viewer)

Tord

Well-known member
Hi,

Has anyone here managed to reverse their Crayford focusing axis L/R? (In order to get the dual speed knob on the left side). I am tempted to give it a try but would like to hear other opinions before attempting to do something that might be a bad idea, ending up with a broken scope.
 
Hi Tord,
I did on mine with no problem, but it depends a little on the design. I think some can't, but it is so easy to do I would just give it a try. On mine all I have to do is remove the single knob, pull out the stem and turn it around. Keep me posted. Which scope?
 
That one has a rack and pinion drive, right? Send me the exact model number of the focuser (or a picture) and I will ask my friend Tommy at the telescope shop.
 
I did it on my SW80ED which has a 2 speed focuser. Doing it is easy. The difficult part is adjusting the focuser afterwards so that it works smoothly. Since I was able to do it, it means it is quite easy...

I have posted detailed instructions on this board as well as other links to adjusting the focuser.

Reversing the knobs - see post #366
:http://www.birdforum.net/showthread.php?t=194800&page=15

Reference to adjusting the focuser - see post #6.
http://www.birdforum.net/showthread.php?t=300206

Have fun !
Jules
 
To be on the safe side, take a picture of the focuser from the bottom, unless the left side looks just like the right. (Green arrow. Flat surface.) If it is the same, go ahead and try to just remove the whole business and turn it around. The mounting screws should be symmetrical. The only problem could be the locking screw as it might not have a hole on the other side of the shaft. Mine did, so there was no problem, but some don't. If it doesn't you can either try to switch the knobs, (tap the shaft in so that it sticks out the right amount on the left side. No adjustment necessary afterwards!) or remove the single knob, pull the shaft through and stick it in from the other side. You might have to loosen the tension screws first.
photoline-80mm-apo-auszug.jpg
 
Thanks both.

Having split apart the focuser on my TS102 in the past (in order to put back a nylon cushion that got loose due to a locking screw untightening) and remembering the challenge aligning the focuser plate and roll I will start by trying to get the shaft out and switch the knobs.
 
I owe you an update on this.

The focuser screws are not symmetrically placed so rotating the focuser is not feasible.

Next I tried what was suggested, switching the knobs and if required the whole axis. The low gear knob was easy to remove but then I ran into issues. Loosening the hex screws turned very difficult with what seems more than enough torque, and I don't want to break the thing. Giving up for now.
 
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I owe you an update on this.

The focuser screws are not symmetrically placed so rotating the focuser is not feasible.

Next I tried what was suggested, switching the knobs and possible the whole axis. The low gear knob was easy to remove but then I ran into issues, loosening the hex screws turned very difficult. No way to loosen them with what seema more than reasonable torque, and I don't want to break the thing.


I don't know about yours but my focuser is a precision mecanism, even if very simple. It is wise to be extremely careful to keep it working smoothly and to avoid ruining it. Replacements are very expensive.
 
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