Orion Optics Crayford Help Needed !

[John]

Can anyone who is using the OC1 Orion Optics crayford focusser please give me some tips on getting it operating well ?. This is the one (picture courtesy of phillsail1):

http://ukastronomers.com/philsail1/image/7747_large.jpeg

I've tried all the adjustments that I can think of, I've sanded the "flat" bottom to the drawtube to make it flatter, and adjusted the 2 hex screws underneath. I've checked the smooth running of the 4 upper bearings as well.

I either get it smooth but with no tension to hold even a moderate size eyepiece or very tight indeed - so tight it's awkward to operate !.

All and any tips on how to get better performance from this focuser welcomed

It looks a nice focusser but is not really performing like one at the moment

Thanks.

[Rocketron]

I'm having the same problem with the OO crayford on my Dob,

Noticed it more since I've recently started using heavier 2" eyepieces.

I agree that it's a nice looking piece of kit

Been meaning to try and adjust it but really not sure how.

Ron

[John]

I've had another go at flattening the flat area of the drawtube with a sanding block. I re-installed the drawtube and carefully adjusted the two tension hex screws on the bottom of the focuser (between the 2 focus wheels) to endure that the axle was pressed firmly against the flat section of the drawtube. It seems better than it was but I'll find out when I try a heavy eyepiece in the drawtube !.

[harry page]

Hi

I have the 3" version

I have found you have to very careful when tightening the bar onto the tube i.e it is easy to twist it so it is not uniformly pushing on the flat area of the tube.

I tighten the screws slowly one at a time to even it up carefully

best of luck Harry

[John]

Hi

I have the 3" version

I have found you have to very careful when tightening the bar onto the tube i.e it is easy to twist it so it is not uniformly pushing on the flat area of the tube.

I tighten the screws slowly one at a time to even it up carefully

best of luck Harry

Thanks Harry

I took a lot more care over that part of the operation this time and it does seem better - I can play around now and see if I can "fine tune" it