balance...BALANCE!! dammit..

[Whippy]

So I bought the dovetail, tube rings and power supply for my HEQ5 mount, and I thought I might just set it up just to get a rough idea of balancing and all that jazz. I've tried to balance the RA axis (got it all nice and level etc etc) and much to my surprise I'm finding it's heavily tipped in the 'scope's favour. No problem I thought, I'll just grab the counterweights from my TAL mount, that should do it. Oh no it doesn't!

Apparently my Skyliner 250PX tube weighs about 12.5 Kg and I've used the two weights that Daz gave me plus the two TAL weights and it still doesn't balance! I've got them all right at the end of the pole and it's still not right.

Am I doing something wrong or something?

[fmeireso]

You should get it balanced with about 16-16,5 kg of counterweights. I use an 10 skywatcher that weights about 12.5 kg(your OO should be lighter no?) and i can get it balanced with about 16,5 kg of counterweights. 2 weights that were included with the mount, a 5 kg weight i bought for body builders wich i clamp between the two 5 kg weights of the HEQ5 and a little 1.6 kg weight also clamped between the 2 x 5 heq5 weights....

The 5 and 1.6 kg 'body builder' weights are very cheap, i did not want to pay 80 € voor a additional HEQ5 counterweight...i bought the 5 kg for 5 €...

[fmeireso]

You don't have an OO tube do you, sorry i misread the post. Anyway you scopes is like mine, so like i proposed it should be fine.

[Whippy]

What's an OO tube?

[themos]

Orion Optics , at a guess!

[FLO]

Extra counterweights are available. Keep in mind that it needn't be balanced to perfection, motors like a slight resistence and tend to work better that way.

[Black Shuck]

Am I doing something wrong or something?

Just in case you are have a look at this link. Its for a Celestron C8 Newt (covers the C6, C8 and C11 Newts) but I can't imagine they can be that different?? (I am happy to be sternly corrected - if appropriate ).

It has a section on scope/mount balancing which might be useful for you?

http://www.celestron.com/c2/images/files/downloads/C8NGT_31062.pdf

Hope you get sorted and out observing soon

Bill£

[John]

One thing I noticed when I swtched from an EQ5 to an HEQ5 is that the latter's balance point is different to the extent that you either need to add significantly more counterweight to balance the same scope or, as some people have done, fit a longer counterweight bar.

It's just a design "feature" of the HEQ5 I guess.

John

[Whippy]

Hm, I'm guessing I'm haven't got enough counterweight to balance it (it's not even close!) and even with my basic grasp of physics as the TAL weights are shorter and stubbier rather than flat and wide, the one nearest the mount probably isn't doing much at all. So I'm off to Argos methinks. And if I still don't get any joy, I'll have to investigate a longer bar for it.

[fmeireso]

What's an OO tube?

Sorry, OO is Orion Optics UK. They are known for producing very lightweight tubes and very good optics.

A 12 inch OO newt F/4 weights about thesame as a 10" skywatcher tube.

[Macavity]

After quite a lot of tedious (experimental!) fiddling around, I was impressed just how well the use of a bathroom scales and tape measure proved as input for a CALCULATION of some scope balance points. That, once I had overcome the PAIN of revisiting those dreaded "applied maths" lessons...

Something for the astronomer:

http://curriculum.calstatela.edu/courses/builders/lessons/less/les1/binary_stars_1.html

[jcm]

After quite a lot of tedious (experimental!) fiddling around, I was impressed just how well the use of a bathroom scales and tape measure proved as input for a CALCULATION of some scope balance points. That, once I had overcome the PAIN of revisiting those dreaded "applied maths" lessons...

Something for the astronomer:

http://curriculum.calstatela.edu/courses/builders/lessons/less/les1/binary_stars_1.html

I suppose this is the reason why 2 scopes of the same weight , one with a diameter of 200mm say and the other of 120mm need different amounts of weights ( or position of weights) to get a balance because the centre of gravity of the 200mm scope is further from the fulcrum.

John

[orion f6.3]

my 10" OO f6.3 takes 20KG to balance (thats a full 44lbs in old money) Orion

[jarbi]

my 10" OO f6.3 takes 20KG to balance (thats a full 44lbs in old money) Orion

Orion f6.3, I can confirm that ! I have a Skywatcher 10" with a Bresser 90 guide scope mounted, and 20 kg is barely enough to balance it. It still feels very stable, but maybe already not far from the upper limit of EQ6...

cheers

Janos