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View Full Version here: : Info needed on my new crayford style focuser


bytor666
09-07-2005, 08:10 AM
I was just checking out my new crayford style focuser and when I tried a couple of eyepieces in it, I noticed something.
When I tighten the tension screw, it shifts the focuser tube ever so slightly "off-axis" leaving a "space" in between the lip of the 2" part of the focusing tube and the part underneath where it rests.(see pic).
there is also 2 screws that can be tightened or loosened in the pic where I pointed this out with a big question mark.
I tried loosening and tightening these screws but I am still getting the off axis shift in the tube leaving that space again.
If anybody knows how I can fix this, or get a full manual for this focuser, I would be all set.
I'm sure it won't degrade the image that bad, but being fully "on axis " when focusing in and out wouldn't hurt either!!!...If anybody knows what I can do...please feel free to drop a line or two on this post....Thanks!!! :2thumbs:
---------------
Mark
12" Gso Scope

Dave47tuc
09-07-2005, 11:30 AM
I have the same problem and not sure why :confuse3:

But I don't see that it makes a difference in the views. :D

ballaratdragons
09-07-2005, 02:46 PM
Mark, I have the Crayford that come with the Deluxe12" GS Dobbie.

I don't have the problem of the off axis shift as my EP's are almost a perfect fit in the focuser tube. I'm sure there must be a fraction of shift on mine but it is so small it is un-noticable.

The 2 small screws are for the Crayford design rollers. Underneath those screws are the rollers that stop wobble and help to make the focuser tube glide smoothly. Apparently, they are either tensioners or oil holes. By tightening them, the tension on the rollers increases, or simply to allow you to oil the rollers. I am trying to find out myself as it is not something I am prepared to touch.