Balancing an 8" Newt

[prova]

Got my Bintel/GSO 8" reflector the other day and just wondering if there are any good, easy to read guides on doing a proper balance so I don't overload the gears on the HEQ5Pro..

Cheers

[Starkler (Geoff)]

Is there something more complex required than just loosening the clutches on the mount and ummm balancing?

[Garyh]

Try this link...
Its more for a side by side setup but its pretty much the same
cheers Gary

http://www.wilmslowastro.com/tips/g1....htm#balancing

[AlexN]

as has been mentioned, unlock the DEC axis rotate it 90° to the left, see if it sits there without you holding it.. now rotate it 180° back towards the right, see if it sits there... If yes to both, DEC is balanced, if the scope continues to fall downwards, the counterweights have to go down the shaft, if the counterweights pull the scope back upright, the counterweights have to be moved up the shaft.

Lock the dec clutch leaving the dec axis horizontal, unlock the RA axis and see if the scope sits level, if yes, its balanced, if no, you have two options.. slide the tube forwards or backwards (whichever is needed) in the rings to achieve balance, or move the dovetail bar in the mounts saddle.. obviously if the front of the tube falls towards the ground, move it backwards etc....

[prova]

Thanks guys

[leinad (Dan)]

One thing that annoyed me(not sure if it matters to much) is when everything is facing the pole and you unlock the RA axis the scope would fall to the left(eastward) due to the weight of the finder scope/telrad & focuser. I'm gonna raid the garage and see if I can find some speakers to use the magents wrapped in cloth to even that balance on either side of the tube at the focuser..

Does anyone know if this balancing is important ? I see some people using this method but no mention of any importance?

I noticed Iceman has a magnet and the rear of his tube. I gather this would have similar effect to being at the top of the tube; on opposite side of focuser?

[Lismore Bloke (Paul)]

I remember going through this on my 10". I ended up weighing all accessories individually - finder, telrad, focusser and making up some weights on the kitchen scales and attaching them directly opposite the item's position on the tube. otherwise it swung around all over the shop with the brakes off.

[Lismore Bloke (Paul)]

I also made up a couple of plywood disks the same diameter as the inside diameter of the tube. These has a couple of bolts drilled through the exact centre. Removed the mirror as the weight is pretty equal. Suspended the tube on these bolts in a couple of simple bearings (V shaped timber screwed together).

i was the able to rotate the tube around and add weight so that there was no imbalance. A bit fiddly, but I can move the 10 around the sky and there is no need for brakes on RA or Dec.

[Ian Robinson]

see attachment, shows how to work it out (pretty closely).

You will need to work out A , B and C for your GEM.

[prova]

Cheers Ian