1) *SOLD/BOB* This massive 4" Crayford was used on APM's refractors before the anodized CNC TMB rack and pinions arrived. It has a 5.940" diameter OD that slips into the mating tube or adaptor, with a V-groove that would allow rotation at the next assembly. The knobs are massive 1.5" diameter, an adjustable-tension knob can lockup the movement. Condition is quite good, the finish is black and aluminum, includes a 4" to 2" compression ring adapter with brass hardware. Several standard tapped holes in the body allow for various finderbracket configurations. The roller works against a replaceable synthetic flat, unusual in a crayford in that the actual machined-flat compression surface will never develop wear grooves from the roller, and the feel can be adjusted by replacing the replaceable element if desired. I can include spare bearings, although it would be difficult to overload this beast. It is not as smooth as the other top-notch machinery above, but at 1/3 the cost and no waiting, I think my price is reasonable at $350 shipped in CONUS, paypal encouraged, no photo available.
2) SOLD:DAVID Unused 2" William Optics compression ring Crayford, Rotatable, with adaptor for Schmidt Cassegrains, never used, includes the 1.25" low profile adaptor. $135 shipped in CONUS, paypal encouraged, no photo.
3) *AVAILABLE* Vintage CRITERION RV-6 newtonian focuser, double brass drawtube, in quite good condition considering its age. The cast base says Criterion on one side and U7 on the other. Added value: Includes a removable ring with brass thumbscrew that slips over the inner drawtube to squeeze the compression fit so your oculars don't fall out; I am not sure if this was a Criterion option. $80 shipped CONUS, paypal encouraged, no photo.
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