[gasman1 (Gary A Sitton)]

I just recently finished swapping my 1.25" (cheap) rack & pinion for a nice 2" Crayford focuser ($150 US) on my 130mm f/5 Newtonian. All I did was to drill 4 1/4" carefully placed holes in my steel tube and fastened the new focuser with the help of some washers to shim the new focuser properly. You should not have to move the primary or get a larger secondary if you get a low profile focuser. My new Crayford is made by Antares and has a nice 2" extension tube built into the focuser. I did not even have to cut a larger hole in my tube to allow the focuser to extend a bit into the tube. The fully racked in distance, from the tube to the eyepiece hole, was actually a bit less than the old focuser without opening the hole for the 2" focuser tube. The Antares, as most 2" focusers do, came with a flush mounted 1.25" adapter which aided in the low profile. I installed the 2" focuser because I wanted to do some photographic work and the 1.25" rig was too flimsy and typically had backlash and side shift issues. The Antares has a second stage 10:1 fine focus knob which is very nice for critical high power work. All my EPs are 1.25", but I just purchased a very nice GSO 2" 2X & 1.5X Barlow and an Orion 2" moon filter all for less than $100 US.