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Can't get proper balance on DEC axis - Help!

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#1 Johnny5

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Posted 15 June 2009 - 10:33 PM

Ok, so I have an Orion Atlas mount and an 80mm refractor mounted to it and can't get it to balance properly on the DEC axis. I have at the back, filter wheel, ext tube and a QHY8, so it's very back heavy. I've slide the the scope as far to the front/objective lens as possible to try to balance the weight, but to no avail.

What can I do? Is there some weight system I can put in front of the scope to balance things out?

#2 Bees

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Posted 16 June 2009 - 12:05 AM

You could try to get a longer dovetail or I've even seen some guys use ankle weights (like the 5 pound ones) put around the front part of the scope.

It will increase the weight of your system but if it helps balance and your weight requirements are still in check, it will be worth it.

#3 DanB

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Posted 16 June 2009 - 01:05 AM

Try it with a side by side lol! I have an 80mm next to a 10 inch newtonian and just went through all of this on the EQ6.
Good news, its doable. Like the last poster said, get a longer dovetail if you cant slide it further forward. I think you may have that same short dovetail I started with.

Before I put the side by side together I had exactly what you have, AT80ED, extension tube, Q453/Q8, 2 counterweights stock with the /EQ mount but I had to use the longer dovetail from my newt to get balance. I didnt try any other weights other than what were on the mount but that would work too.
Good luck, you're close.. Seems like everything astronomy is like this.. just one more 40 dollar part lol. Dan

#4 Charlie Hein

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Posted 16 June 2009 - 06:36 AM

I use a longer dovetail - the balance point is way back of center with the 80mm refractor.

#5 DeanS

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Posted 16 June 2009 - 11:09 AM

I use a couple small dumbell weights like shown. I put a wood dowel in the large central hole as a bushing, then attach it with a short sction of all thread, fneder washers, and wing nuts.

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#6 DanB

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Posted 16 June 2009 - 10:49 PM

Wow, mine doesnt seem to be as back end heavy. I was able to get it without going past the edge of the saddle with my dovetail.. with a Q8 imager and extensions. That camera is pretty heavy heh!!

I liked the ankle weights idea, seems pretty handy and you can get all kinds of different weights.
Hope you get it!! GL, Dan

#7 Charlie Hein

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Posted 17 June 2009 - 07:43 AM

Wow, mine doesnt seem to be as back end heavy. I was able to get it without going past the edge of the saddle with my dovetail.. with a Q8 imager and extensions. That camera is pretty heavy heh!!

I liked the ankle weights idea, seems pretty handy and you can get all kinds of different weights.
Hope you get it!! GL, Dan


I have an SBIG ST2000 hanging off the back which isn't a light camera. Older DSLR's will be comparatively heavy too.

If you're using a short guide scope then you can also run it forward to help balance the load.

#8 mewmartigan

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Posted 18 June 2009 - 08:21 AM

Hi, I don't know how many counterweights you are using but On my Atlas I could initially balance in RA with one counterweight but then couldn't balance the DEC.
Once I added the second counterweight and rebalanced in RA, I was able to balance the DEC. And this is with a DSI on the guidescope and a Rebel XSi on the main. So I am relatively back-heavy also.

In short, if you aren't using both couterweights, try that :)

#9 DanB

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Posted 18 June 2009 - 11:18 PM

Yea I guess that is a bit heavier than mine. I almost bought that ST2000 but price won.

So the bulk of the imager wont allow you to push the full assembly any further forward, hmmm!?

The only thing I would try if it were me is asking Anthony Davoli (ADM) or similar. He haas been a wonderful problem solver on a couple of occasions for me.

GL, hope you get it before clear skies!! Dan

#10 Charlie Hein

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Posted 19 June 2009 - 06:29 AM

I'll see if I have any pictures of the rig and post them so that you can see how I solved this, but I'm out of town at the moment and may not be able to find something until Monday or so.






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