Duncan,
I'm using the 10:1 fine focus Guan Sheng made Crayford,
http://www.andrewscom.com.au/images/...gs_focuser.jpg
Around a $120 it's a great piece of kit.
You can buy Crayford focusers from Moonlite in the U.S.A, but you're paying approx 3X the price.
I've found the G.S model to be smooth and works very well.
John
