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Weights for refractors


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I've been fussing with a balance issue on my frac. Fixed it with some washers but its still not quite right. I've seen some pictures of fracs with side mounted weights along a threaded shaft. Free to move up and down the tube. I've been trying to find something like that and have had no luck. I can put together the threaded rod right angles and all but don't know where to get the weights. My rings have m5 threaded spots to mount it. Just seems like it would be much easier to move that weight up and down to get perfect balance instead of adding washers to the two rings. I can't get it exactly balanced that way. So if anyone knows where I can get the weights or a whole setup I'd appreciate a link.

Griz

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No place to attach another dovetail it has to be on the side  of the scope. There are two M5 threaded holes on the sides of the rings I'm assuming are for weights but just using washers its very difficult to get the right number of washers on each ring so the effect falls somewhere between the rings. I'm using an external battery for the DSLR so the weight is different. The battery plug for the external battery doesn't weigh anything compared to the real battery. But even putting a regular battery back in doesn't fully fix the problem. The camera is just heavy on one side. I can rotate the focuser assembly and almost get it to balance.  I wish the holes were larger. I can't find any angle fittings that size I was thinking I'd get a threaded rod and make one. Then just find some weights and drill and tap them to fit. M5 is pretty small. Hopefully when I'm able to get the ccd it will be balanced better than the DSLR and the problem will go away. Its only a problem when the scope is almost straight up. It has a big moment at that point and if you turn loose of it the thing will accelerate and almost go full circle. When its parallel to the ground or almost anyplace in between its fine. I'm starting to wonder if the axis isn't sticking making me think its balanced when its actually not. Another month of clouds and gloom here according to the forecast. Seriously thinking about taking a road trip for some clear sky soon. Big Bend area is awesome for imaging and its been clear. Last set of images had a huge doughnut in them I couldn't get out. Looks like it was me not putting the cover on the viewfinder. That night the moon was behind the scope and I was shooting low away from it. I played with a led here in the house with it and was able to recreate a very similar pattern. And I know better I just was in heat to try out my new toy :) 

Griz

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Thanks thats close to what I want. However I think I have it solved by offsetting the guidescope just a bit to the light side of the tube. Instead of mounting the clamps on the scope rings I put them on the WO rings. The clamps have 2 holes and the WO rings have 5 threaded holes spread across the top. So by moving the clamps around till I was able to get the right offset all is well. Wasn't much but when I put the dual saddle on and it balanced I noticed it wasn't much of an offset. So the weight of the Borg camera and rings was enough. And putting the clamps on the WO clamps allowed me to mount a dovetail to the guidescope so it fits in the main saddle of the scope in case I go to that method of polar align. I have a call into Losmandy to see if the AltAz adjuster block for the GM-8 will bolt up to what I have. If so I'll just go that way with the mount. Use the Meade adapter either on the pier or pick up a meade field tripod. I think moving to a G-11 is just too much weight for me and it would end up in the garage gathering dust. I weighed everything and its 22.5lbs. Well within the capacity of the SL. Hoping the mods I made to the wedge will solve my problems and I can pick up the STF-8300 this month instead of spending more money on my mount.

Griz

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