Improved dovetail for AT RC8 on Celestron CGEM?
Posted 17 February 2010 - 11:24 AM
I would like to mount my AT RC8 on my Celstron CGEM.
The RC8 has a Losmandy-style dovetail, which is not really right for the CGEM. The proper dovetail for the CGEM would be slightly narrower, and have much deeper dovetails so that the dovetail would engage over the entire height of the clamp -- the Losmandy only engages over the upper 30-40% of the clamp, and does not inspire confidence. IOW, the Losmandy dovetail is nowhere near as "deep" or "tall" as the dovetail that the CGEM is expecting.
Are there any plans to offer an alternate dovetail for this configuration?
Also, is there a name / standard that the CGEM dovetail adheres to? It looks to me from pictures that Celestron uses an extrusion (as opposed to a machined plate) as their dovetail -- an interesting approach to the problem. I suppose a compatible dovetail plate could be attached to the Losmandy plate on the RC-8, although I would prefer a complete replacement as the cleanest solution.
Posted 17 February 2010 - 12:04 PM
But if you like the "Vixen" one I'm sure someone would be happy to swap with you.
Posted 17 February 2010 - 12:35 PM
The Losmanday Dovetail actually doesn't fit on the CGE as it is adjusted right out of the box. There is a screw that limits how much the clamping jaw can open on the CGE. IT is a very simple matter to either back out the screw a few turns to allow the jaw to open wider, or alternatly (and the approach I personally choose) replace the screw that limits the amount the clamp can open with a longer one so that the clamping jaw can open a bit wider but still have enough threads in it to engage into the hole in the saddle. It is likely that the CGEM has a similar setup.
I have a Losmandy saddle on my Meade LXD 750 and I use my $4000 refractor with a Losmandy dovetail on both the Meade mount and the CGE mount and never felt for a moment that there was anything to be concerned about. The fact that the dovetail sides and thicknesses are different really doesn't matter in practical use.
Posted 17 February 2010 - 11:34 PM
Posted 18 February 2010 - 04:31 PM
Posted 18 February 2010 - 06:42 PM
Posted 18 February 2010 - 09:04 PM
Hmm ... I need to decide whether I want to do that saddle with the stock Losmandy plate under the RC8, or make a custom, much longer plate that can support a DSLR or FLI ML-series given the long extension of the RC8 ...
Thanks for the tip to the ADM website!
Posted 19 February 2010 - 01:37 AM
Posted 19 February 2010 - 11:16 AM
Am ordering the saddle today.