ED80 and 450D Dec Balance on an EQ6

Benno85 (Ben) · #1 08-01-2010, 08:35 AM

Morning All,

I seem to be having a bit of a problem achieving balance on the Dec axis using the SWED80 with Canon 450D attached. The problem is once the extension tube and camera are on the rig becomes very "back-heavy" (due to the weight of the camera), and I have no more room to slide either the OTA forward in the rings OR the dovetail forward on the mount.

Any and all responses welcome, the cheaper the better

Marke (Mark) · #2 08-01-2010, 08:42 AM

You will most likely need to add a small counter weight to the dovetail
up the front to allow you to keep balance. Losmandy and ADM make
these along with several other companies.

Benno85 (Ben) · #3 08-01-2010, 09:01 AM

Thanks Mark, am I right in saying that the dovetail counterweights are simply smaller versions of the standard counterweights and are attached to the unused mounting holes on the front of the rail?

Perhaps I could knock up something instead of paying for them (I keep getting letters from someone named Bill!!!)

Omaroo (Chris Malikoff) · #4 08-01-2010, 09:24 AM

One of the things that I used to do Ben, was to buy a slab of small (1" sq.) lead weights with the sticky backing - ala what they use in car tyre places for wheel weights. Then, get some sticky (i.e. stick-on) Velcro and stick appropriately-sized squares of the hairy side onto the back to the lead weights.

Then - Wrap a strip of non-sticky hook Velcro around your OTA near the end or your dew shield. Simply apply as few weights under the OTA as required for balance.

Marke (Mark) · #5 08-01-2010, 09:35 AM

Quote:

Originally Posted by Benno85

Thanks Mark, am I right in saying that the dovetail counterweights are simply smaller versions of the standard counterweights and are attached to the unused mounting holes on the front of the rail?

Perhaps I could knock up something instead of paying for them (I keep getting letters from someone named Bill!!!)

Yep they are much smaller usually have a little clamp on them, but
easy to knock up something yourself. Try sports store for some small
ankle weight or similar and try attaching those.

iceman (Mike) · #6 08-01-2010, 09:39 AM

Quote:

Originally Posted by Omaroo

One of the things that I used to do Ben, was to buy a slab of small (1" sq.) lead weights with the sticky backing - ala what they use in car tyre places for wheel weights. Then, get some sticky (i.e. stick-on) Velcro and stick appropriately-sized squares of the hairy side onto the back to the lead weights.

Then - Wrap a strip of non-sticky hook Velcro around your OTA near the end or your dew shield. Simply apply as few weights under the OTA as required for balance.

I like this idea.
I imagine it would work better than my strip of velcro which tentatively holds a 1.25kg dumbbell weight in place

troypiggo (Troy) · #7 08-01-2010, 10:00 AM

I had the same problem and almost the same gear as you. I bought a dovetail mount from Bintel and use this to connect the guidescope to the imaging scope. That way I can slide the guidescope up and down to get the correct balance.

Benno85 (Ben) · #8 08-01-2010, 10:25 AM

Thanks a million Chris, I'll be walking next door to Mitre 10 on my lunch break today!!

Troy, cheers for that link for the mount, do you bolt that mount to another dovetail in place of adjustable guidescope rings?

troypiggo (Troy) · #9 08-01-2010, 09:09 PM

Quote:

Originally Posted by Benno85

Troy, cheers for that link for the mount, do you bolt that mount to another dovetail in place of adjustable guidescope rings?

I have a bar that the guide rings are connected to. The mount plate is bolted to that, facing down. On top of the imaging scope is a dovetail bar as well, and that's what the plate clamps onto. Does that make sense?