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CGE Pro counter weight shaft extension?

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#1 George P Dunham

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Posted 31 January 2013 - 09:57 AM

I am looking for a CGE Pro counter weight shaft extension. I know they used to be available through Celestron but I cannot find them via Google. Or is there a DIY alternative?

#2 123456

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Posted 31 January 2013 - 04:32 PM

i made one for my sirius mount , i went from 11" to 20" and was able to
remove 22lbs of CW. big difference

#3 Whichwayisnorth

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Posted 31 January 2013 - 08:58 PM

I may be wrong, and I usually am, but wouldn't a longer CWB drastically increase the momentum when the mount stops and resulting oscillation?

#4 LouHalikman

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Posted 01 February 2013 - 08:05 AM

Yes -- the closer the weight is to the center of motion, the more stable the system will be. IMO, a longer CWB should only be used if balance cannot be achieved with weights on the standard CWB length.

I balance my C 14 HD and an 80 MM carbon fiber APO, focal reducer, diagonals, and camera with 4 22# weights on the standard CWB length. The system is stable. Lou

#5 George P Dunham

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Posted 01 February 2013 - 09:41 AM

I currently have things well balanced with 4x22# weights, but I will be adding a heavy celestron reducer and I am afraid I will run out of room. I would only need a few more inches at most. I guess the answer to my question is that the part is no longer available. I understand the possible problems associated with added inertia with an extension and the slew up and down problems. Thanks

#6 LouHalikman

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Posted 01 February 2013 - 02:27 PM

Mine balances fine with 4 22 # weights including the heavy Celestron reducer AND an 80 MM CF APO on top. You should be fine. You can save a pound or two by substituting a Telrad for the optical finder.

#7 wolfman_4_ever

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Posted 01 February 2013 - 05:58 PM

I stuck a ADM CW bar in the end of my shaft. I had to retap the end for the proper threading. Celestron is metric while the ADM bar is imperial. It's the same diameter. I just had to stick the proper imperial threaded tab up there. Anthony, at ADM, might be able to make you one in metric.

I then screw 1.75 or 3.5lb ADM weights on the end. Currently using a 1.75lb'er. Makes a great bar stopper too. This length allows for 2-3.5lb weights and 1 1.75lb weight max. I never go that much though. I did this mod after I received my HD11 focal reducer.

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#8 123456

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Posted 03 February 2013 - 12:23 AM

hello guys


>>I may be wrong, and I usually am, but wouldn't a longer CWB drastically increase the momentum when the mount stops and resulting oscillation?

The center line of the mount cant tell if you have 33 lbs at 6" or 11 lbs at 15"
hanging on the CWB so there is no increase of momentum
When slewing at speed then stop there is a little oscillation but by the time i get in place
it is stopped when tracking i don't see any oscillation and a thump to the eyepiece is as good as when i had the 33 lbs


>>Yes -- the closer the weight is to the center of motion, the more stable the system will be. IMO, a longer CWB should only be used if balance cannot be achieved with weights on the standard CWB length


I cant say it may be more stable i checked both ways and pulling on the OTA it didn't try to fall over any easier .it really done a lot better then i first thought !

But the sirius bar is really short and 33 lbs was a lot to move .with just 11 lbs i can carry the mount out with the weight on

I had the OTA "AR6" on a LXD55 mount for a while and used just 22 lbs at the very end of the CW bar and still could have used 2 lbs more but it worked .

Switching to the sirius mount and the AR6 OTA does mounts off center line that much more to cause the added weight ..... the AR6 plus the add ons is close to 30 lbs

I made the bar out of aluminum as a test . since it looks to cure my problem what
I will do now is make one from brass .. less flex and should end up a little shorter
then the 20" aluminum bar

my goal was to lighten the load as much as i could ..this did cut 22 lbs off

.......... YMMV

Joe

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