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Is there anyone who can Improve the Old C8 Fork?

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#1 Muffin Research

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Posted 15 June 2009 - 07:28 AM

Is there somebody or are there aftermarket solutions I can get for improving my '81 Orange tube C8 fork mount??
The thing is I love that scope the way it is, I don't want to mount it on something else like an EQ.
But I know the weak point is a bit the fork mount.
I'd like to keep the package as is, it's in very good condition, and the optics are great, nice startest when collimated and other scopeowners say wow when they look through it as if they don't expect it from a SCT. ha!

I'm mainly referring to Clutch & DEC gear upgrades, maybe the RA to if It can be improved. without messing up the original look too much.
Might be a bit silly but a lot of us also buy with our eyes and the thing resides in the livingroom when clouded so, you want something nice to look at when not looking through it :p

#2 tim53

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Posted 15 June 2009 - 09:15 AM

I do believe there were aftermarket RA slow motion controls from Tuthill that were finer than the stock slow mo in RA, and perhaps a JMI Motodec could be added to minimize shake from manually adjusting the dec.

Short of replacing the fork with something like an Ultima 8 fork, I don't know of any mods to the original fork mount that wouldn't alter the lines drastically.

I have a ~1980 C-8. I tested the PE of the drive, and found it surprisingly good, considering it's a spur gear drive - around 20 arc seconds.

-Tim.

#3 Muffin Research

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Posted 15 June 2009 - 09:26 AM

Thanx, Tuthill and JMI, i'll search a bit for those.
My mount has motorized DEC with a little rubber band attached to the DEC knob. It works but you know it's not that great.

or some very handy guy that can improve the workings of the mount within the existing format of the frame.

I'm probably reaching but it's just an idea that came to mind.

#4 Muffin Research

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Posted 15 June 2009 - 09:29 AM

Or maybe the Beyers Celestron fork mount? like this? mount

are those better than the standard ones? the clutches look a lot sturdier to begin with... maybe if I can find one of those..

#5 Muffin Research

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Posted 15 June 2009 - 09:37 AM

mine is like this...

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#6 tim53

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Posted 15 June 2009 - 09:50 AM

The fork with the Byers drive would be a good choice as well. Not as beefy as the Ultima (which has the Byers gear also), but should have the low PE of the Byers gear.

You're fortunate to have one of the original Celestron drive correctors. I've been looking for one of those offhand for a while now. They're pretty scarce.

-Tim.

#7 Muffin Research

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Posted 16 June 2009 - 07:55 AM

Yeah the Dual Axis Corrector drive it works, and it could easily be one of my guitar effect pedals :grin:

Actually the Setup in the link of my third post would be my ideal for the C8 if motorised dec was installed controllable with the Celestron DAC
the 90° Finderscope, the Beyers drive, the clutches look a lot better than on my fork, and the Wedge and tripod also look a lot better, a wedge like that I want, where I can adjust to polar align with turnable knobs for more smooth action and precision instead of the allen keys cursing i have to endure now I also don't have a latitude adjust like in the picture so there's nothing holding the weight yes, there is a very small one with a puny screw positioned to the side of the mount, it's just *BLEEP*... to much cursing involved.

#8 Jimmy2K63

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Posted 19 June 2009 - 09:25 PM

The Byers drive (worm gear and worm) has been mentioned several times and it is a great upgrade. Can you still buy it?

I'm not sure what you are after, but I have seen some great photos taken with the standard drive in the C8. I adapted the little DEC motor that comes with the Celestron dual axis drive corrector to run the tangent arm dec adjustment on my Cave the same way as one the C8, with the rubber geared belt - pretty torquey little motor for being so small. I still have it if you think you might need one. It's just a (think 12 volt) well geared DC motor though.

I just don't know if you can still find parts to do this nowadays. Isn't Tuthill out of business?

#9 Muffin Research

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Posted 20 June 2009 - 10:53 AM

Prolly most of it has to be searched secondhand, however JMI still make the DEC motor that can be used on the old C8's.

What i'm after?
hmm the same mount with better clutches and gears? :grin:
even to the point maybe just somebody modifying or custom building.

but yes you are right the supplied RA Drive works actually pretty great, and if you Polar align to oblivion it also tracks pretty well.
I have the little rubber belted Dec motor, and use it.

it's just the Beyers version of the Celestron mount looks pretty okay so that might be a cheap option if I can find a used one, the clutches seem sturdier than the standard ones as well, though I don't know if that counts for the mechanism behind them as well.

#10 tim53

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Posted 20 June 2009 - 12:11 PM

Keep watching the classifieds for a fork/base combo. They do crop up semi-regularly for not much money.

-Tim.






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