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O-Ring

Started by Larry J, 08/14/2009 03:31PM
Posted 08/14/2009 03:31PM Opening Post
Does anyone know where to find (or the size of) the o-ring that is used on the ubiquitous 6x30 finders in the dovetail style mount stalk?
I did some cursory checking without luck thus far and thought someone here might be able to speed up my process in finding a replacement.
Thanks.
Posted 08/14/2009 05:27PM #1
Larry:

I have several O-rings I picked out at a machine shop that has a complete selection. Based on the measurements, I believe they are 2-023's, they are a nice fit. I suspect 2-024's would also work.

For the larger 50mm Synta Finders, something in the range of a 2-031 to 2-033 would probably work, I think the ones I selected were 2-031's which require some stretching and will stay in place nicely. These are probably supposed to be metric sized O-rings but these inch unit rings work quite well.

After I graduated and began my first job as a mechanical engineer/crackpot, my boss gave me a copy of the Parker O-Ring design handbook and I have used it ever since as a bible...

http://www.parker.com/literature/ORD%205700%20Parker_O-Ring_Handbook.pdf

Jon
Posted 08/15/2009 12:49AM #2
Larry Janowicz said:

Does anyone know where to find (or the size of) the o-ring that is used on the ubiquitous 6x30 finders in the dovetail style mount stalk?
I did some cursory checking without luck thus far and thought someone here might be able to speed up my process in finding a replacement.
Thanks.

In years past, I've received replacements from both Celestron and Orion. Simply pick up the phone and call the parts department...they'll usually cooperate with you. Now, I purchase them at the hardware store. Almost any store has them in the plumbing department. Often they come in multiple packs or variety packs. And yes...they're dirt cheap.