markse68 Posted January 26 Share Posted January 26 (edited) No point having a nice mount with smooth action if you have to put the brakes on to counter it's balance shift as you go from horizon to zenith- this has been bugging me for a while now so I cobbled together a balancing device for my rig. The trouble is it's easy to get horizontal balance just shifting the scope along its dovetail rail but heavy eyepieces and finders that stick out from one side put it really out of balance as you tilt up. My current finder assembly alone weighs ~1.8kg and its mounted to the top of the OTA. So I find myself having to tighten the brake or shift the balance depending what altitude I'm aiming at which is quite an annoyance! I started with this crude looking but compact weight I made from 1.2kg of roofing lead sheet laminated together with double sided tape and formed to fit the tube, and spaced off the tube by layers of foam. It worked fine with my old Skywatcher RACI but that was a lot lighter. I tried spacing it some more with the additional white foam but it never worked perfectly and I realised it really needed to be adjustable as changing eyepieces threw it out and again the brake was needed. I've been picking up useful looking bits over the past few months- a nice small 850g counterbalance weight in SS and a second hand ADM MDS accessory clamp. A length of aluminium bar keeps the overall weight down and allows adjustment of the weight in or out from the OTA. I looked for an MDS accessory rail in the classifieds for a while but I don't think I've ever seen one come up second hand and they are way too expensive new so I drew this bracket thing up and had it printed in nylon. I didn't really want to drill any holes so it's mounted with a webbing strap- I still have to sort that out as I don't want a bulky ratchet strap and the luggage strap I'm using here isn't really very secure. Rubber feet pads are glued into recesses to stop it sliding around on the OTA. I'm fairly confident that the nylon print is plenty strong enough and should survive repeated removal and refitting of the ADM clamp- it will be permanently mounted to the tube. I can now achieve perfect balance in any position and that will make me a much happier observer I'll just have to be careful not to keep knocking the weight bar as it sticks out 20cm- hopefully that won't be equally or more annoying... Mark Edited January 26 by markse68 photos 4 Link to comment Share on other sites More sharing options...
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