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mental4astro
20-02-2015, 08:31 AM
Hi all,

I have an orange tube C8 on its original fork mount. Should the worst happen and the OTA is damaged, would it be worth the exercise to put a newer OTA onto this fork mount? The mount, while not a spring chicken, it has been very well looked after and a workhorse. It is a simple syncronos RA motor that just works. No fancy electronics to fail.

As I don't do photo, accuracy of the drive isn't a major consideration.

But this wedge mounted scope does get the shakes easily. I've managed to get this much more under control, though this is a time consuming task while setting up.

I do have a german eq mount that can take a C8, but I find the fork mount very easy and convenient to use with my sketching. I use my C8 principally for the Moon and planets, but occasionally for outreach nights.

Another question is, how do contemporary forks' stack up vibration wise? I realise that much of the root problem for the vibration I experience is the wedge itself.

:shrug:

Cheers,

Mental.

Camelopardalis
20-02-2015, 10:42 AM
Mental, apparently only the OTAs fitted to the fork mounts have the holes pre-drilled for the side mounts/clamps that attach to the fork. You're a resourceful chap, I'm sure you'd know what to do ;)

As for vibration, you know I use a Nexstar 8SE with my Edge HD 8" ota and it has the 1.5" steel legs, and avoiding the shakes - at least on turfed ground - just requires a little care when focussing. On the "other side" folk have upgraded their legs to some degree of success. In the case of the SE mount, the single arm is also responsible for some flexing no doubt.

Have you considered making some nice wood legs for your mount to see if that damps the vibration any?

GrampianStars
20-02-2015, 10:51 AM
Hey Alex
I added a fixed cross bracing & shoulder bearings to the standard Meade wedge
& it suddenly sobered up no more shakes :P

mental4astro
20-02-2015, 11:15 AM
Thanks lads.

Dunk, some SCR tubes are made with the fork mount holes and mounting screws fitted. I have noticed though that the 8SE doesn't have them. You are right in saying I'm not shy to persuade an 8SE develop these mounting holes... :rolleyes::lol:

Rob, your suggestion on bracing the wedge is an excellent one, and one I'll fit to my wedge this weekend.

Question remains though, is it a viable option to refork an OTA to this old fork mount? It is perfectly fine and seems such a waste not to reuse it with another C8 OTA.

Camelopardalis
20-02-2015, 11:30 AM
If you like the mount, then the question surely becomes why not?

One other thing to consider - is the mounting of the ota into the fork itself reversible? Given the simplicity of the older mounts, and in your hands, I'd be fairly certain ;) The reason I mention this is that reports of people deforking Celestron's CPC saying that it's a one-way, irreversible operation. That's what put me off those beasties (oh yeah and the price :D )

mental4astro
20-02-2015, 09:01 PM
You've answered the question for me. Thanks Dunk :)

Alex.

Camelopardalis
21-02-2015, 11:24 AM
:)