This is quite the lengthy tale, so please hang in there!
For years I've been wanting to upgrade my 5" refractor's stock focuser with a
GSO 1:10 fine focus rotatable Crayford focuser, but was reluctant to spend the money needed: current price is $223 USD: for focuser ($155, AgenaAstro) and 5.125 inch adapter ring ($68, Scopestuff). Of course this upgrade is cheaper than most when compared to more deluxe focusers such as Moonlite, Baader, etc! But I have always operated on a shoestring budget whenever possible.
Last week, on another forum's classified section, I found and bought a used
GSO focuser complete with Antares adapter ring to fit my scope for $110 delivered! I couldn't resist. It arrived this weekend and I removed the stock focuser, noticing the oddly long drawtube.
I read where the factory focuser may require an extension when replaced with an upgraded focuser according to Scopestuff and a thread on another forum. IDK if I have one stashed somewhere? Guess I'll have to wait and see....
I removed the factory focuser and noticed tape around the end of the tube, apparently needed to fit the focuser flange tightly. The Antares adapter ring wouldn't fit onto the taped tube, so I removed the tape and cleaned off the residue with alcohol. Now the adapter ring fits perfectly but there are no threads on the adapter ring or the tube! The original focuser had threads for the screws in a one-piece casting made to fit behind the tube, so great idea there!
I'm thinking my best choice is to buy the correct size nuts to fit the screws to attach the adapter on the tube. Will it be okay to do that? Also, will I need washers?