impromptu counterweighing

[Andrew*]

So after little success with the 4.5" on the EQ5 without a counterweight the other night, I decided to take some time to balance the scope properly. First I put the scope central on the mount, so even with extra weight on the open end (SLR in the focusser) it doesn't tip forward when I loosen the declination axis lock. First part done.

Then I tried to use the EQ5's counterweight, but even right at the base of the bar, it pulled the whole scope round

Right. Obviously I can't use that. This is where my very limited practical skills are turned to. So I got a plastic bag and hung the jug on the very end of the counterweight bar (I want as light a counterweight as possible). I found mum's fine bone china teapot and filled it with water, and started to fill the bag. OOPS! It wasn't waterproof, so I got some old bank statements wet, thank god!

I replaced the bag with a plastic measuring jug hanging dangerously on a piece of string. It was a bit of an unsteady solution, but it did the trick. The idea was that the volume in ml of water needed to counterweigh the scope would be the same in grams. I filled the jug with water and carefully loosened the RA axis clamp, but it was still too light. So I emptied a little water and found the heaviest small objects around. I popped them in the water, one by one until the scope was generally stable, then weighed the total counterweight. It was only 1.6kg. Great, Second part done.

Now I need to find something weighing 1.6kg and find a weigh (!) of putting it on the counterweight bar. Any ideas?

Andrew

[magician]

Eureka!

[Kai]

How about a roll of lead flashing used on roofs etc,its easy to cut and weigh,I bet you can pick it up fairly cheap at a builders merchants.

Get yourself a large jubilee clip to secure it and bobs your uncle

[iancandler]

I take it that 1.6 kg was measured at the end of the arm? if so you should be able to get away with a 2kg counter weight and move it further up the arm towards the mount. teleskop service do some though im not sure of the price.

[SteelRat]

Weights are cheap, mums 'fine china teapot' is expensive, bags have holes in and lead is poisonous. Do the math.

[geppetto]

Nip down to the local sports shop and look in their rack of weight lifting weights.

All sizes and very cheap. You just need to find a way to clamp them on the mount bar.

Hole size will be too big (I drill and tap them to fit a secureing bolt)

[Kaptain Klevtsov]

Just make sure its on securely. If it drops off and the whole shebang tips over there will be tears.

Captain Chaos

[AndyM]

I found mum's fine bone china teapot and..........

Hope your mum doesn't read this forum otherwise there will be tears.