Using a scope that is polar mounted required that both axis be balanced. I set out to do this by adding a 2D counter weight system to the underside of the scope. I quickly learned that this was no good. I then modified the 2D system into a 3D system. This was better but not perfect. On a polar mounted scope with the cwt system mounted on the OTA the balance points change with which parts of the sky the scope is pointed and depending on what accessories are attached. I realized that the best way to balance the scope was to balanc
e the scope before adding the accessories. The Meade fork mounted scopes have a motor and gear system in the right fork and nothing in the left fork. So I figured the best way to balance the scope is to add weight to the left fork. I have read of accounts where folks Velcro ankle weight to the left fork but I wanted something more permanent, something that would not require assembly on each use of the scope, something not too obtrusive looking. So I decided to add the weight inside the left fork arm.
Adding the weight required removing the Dec circle and seven Allen head screws that hold the cover on, four on the inside of the fork and three behind the Dec circle. There are two Phillips screw on the bottom but they only hold a sliding cover.
I fashioned the weight for the fork out of 1/8” sheet lead. They were cut to fit inside of the fork arm leaving room for the tangs of the cover to slide by. The fit over the 4 mounting screw pillars and I added a piece of foam to keep them from shifting or rattling. My scope took about 4 of these pieces of lead. I balanced the scope with the stock finder and Telrad attached as I always use these items.
I next set out to balance the scope with the ST80 attached. This was easily achieved with the 3D cwt system. A little fine-tuning and my LX90 is now balanced. I can easily rotate the scope to any position and have it stay there without any clutched engaged. The motors rotate and pivot the OTA little noticeable change in motor in pitch
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