Thread: My 3rd rebuild
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Old 26-08-2009, 08:58 PM
Jone5y (Steve)
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Jone5y is offline
 
Join Date: May 2008
Location: Albion Park, NSW
Posts: 49
Obviously a scope that stands near 6 foot tall has limitations, even if it is spit in 2 pieces, so I made the decision to convert to a truss style design.
Part of the original tube was retained as it was made to accommodate the Novak primary mirror cell and the rest of the scope was constructed around this.
The trusses are held in place via split blocks of tassie oak left over from a deck I built. Tension on these is controlled by a cam action bike axle clamp. The spider has been constructed from some Al angle but flexed a bit and lost collimation on elevation change and has been replaced with an astrosystems unit.
The connections to the UTA are a modification from the many variants I saw online. They too are tensioned via a cam action bolt.
Due to the lack of following any formal plan as such, the altitude bearings were required to be somewhat oversized (balance issue). They are covered in dimpled Al and ride on teflon from the original scope.
The whole shebang requires a little collimation upon re-assembly but it's nothing out of the ordinary.
If I was doing It again I would construct more of a plan in the beginning to fit the UTA inside the rocker box when dissassembled and make the altitude bearings of a lower profile.
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