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Losmandy G 8 clutch system

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#1 jnewton

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Posted 04 December 2012 - 06:21 AM

I am looking for a good mount for a TV102. I keep coming back to the Losmandy G8 because of the clutch system which lets you move the scope by hand without losing the go to alignment. Are there any other mounts that have this feature? :question:

#2 orlyandico

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Posted 04 December 2012 - 06:23 AM

well finding a G8 with the encoders needed for that "no goto alignment loss" is going to be a challenge.. Losmandy has discontinued the encoders for the G8 and G11.

also the Gemini 2 currently does not support the encoders (although the port is there).

#3 jnewton

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Posted 04 December 2012 - 06:30 AM

Thank you for the info. Even without the go to, do other mounts have a slip clutch system, or do you have to loosen the axes and retighten each time you move the scope by hand?

#4 Startraffic

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Posted 04 December 2012 - 08:17 AM

jnewton,
You can try to get a set of encoders from JMI.
As Orlyandico said, the original Losmandy encoders haven't been made in years & are becoming harder to find. There have been a number of requests to Losmandy to put them back into production but so far they haven't. It would be nice, & they do work very well.
If you get encoders, the older Gemini-1 system does support those, & more of them are coming on the market as the owners change over to Gemini-2. The new Gemini-2 will support encoders eventually, but Rene' Goerlich hasn't written the code yet. He has been adding features (PEC, PAA, PAS, etc.) and debugging them as the firmware gets developed. External encoders is on the list of features that G2 will support.
I have an older HGM-200 & G11, both with the external encoders. The G11 has G1 & directly reads the encoders fine. The HGM I've put my old Sky-Commander back in service for the external encoder interface. I do outreach with the BSA & the Cubscouts invariably put their hands on the OTA & push it off target. Not having Encoders is not really an option. Good luck.

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#5 orlyandico

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Posted 04 December 2012 - 09:43 AM

i don't think the slip clutches are available on other mounts except the G8 and G11.

that said, i have read so many instances that the slip clutches get finicky, you have to replace the cork every so often, etc.

IMHO the old AP mounts have the nicest encoder interfaces, they look integrated with the mount. Pricey (for a 20-year old mount) though and quite rare.

the Argo Navis seems to be the best bet in DSC's. I'm beginning to think I should have bought one instead of converting my AP600E to GoTo...

#6 RAKing

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Posted 04 December 2012 - 12:21 PM

A-P also uses slip clutches, but the same caveat applies with them. You will have to re-synch.

I have a GM-8 with encoders and it's a great little system. I like it for public outreach because if someone grabs the scope, I can easily get it back on target. BTW - there is no cork in my Losmandy mount.

Cheers,

Ron

#7 hottr6

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Posted 04 December 2012 - 12:59 PM

Slip clutches are used on the Byers 812, and maybe others of Ed's mounts. He uses teflon, not cork. My mount received heavy use by a college for nearly 30 years and the clutches work perfectly.

Any encoder can be made to work.

#8 mistyridge

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Posted 04 December 2012 - 07:54 PM

My G11 clutches have no cork in them. :shrug:

#9 Skyshooter

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Posted 04 December 2012 - 09:08 PM

Nope, My G8 clutches have no cork either... no problems with the clutches and even if there were it's an easy mount to replace the pads on. But... like has been said above, if you want a GOTO mount with clutches so you can use it as push to as well you can use the GM8 but it will lose it's synch for goto if pushed. The encoders are needed for that. Nobody, even JMI has a solution for that anymore. Bummer, but as was stated above, It's in the works and the new encoders will have a higher resolution when introduced (from what I've heard).

CLS
Ed

#10 orlyandico

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Posted 05 December 2012 - 12:45 AM

I think the Gemini G53f (no relation to Dr Goerlich) has this feature... it uses a friction roller that can slip when pushed, and has internal 72K tic encoders on both axes.

Doesn't use a worm wheel and large payload. Not cheap though. I was looking at this mount instead of a Mach1 but at the end of the day, old but proven technology wins over promising new but not quite mature technology. Particularly when you're forking out that much moolah...






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