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Update
Just a quick update, I have been waiting on iStar to get back to me on the replacement objective. I received the tracking number so it is on its way now. Maybe by the end of next week if I am lucky.
In the meantime, I received the flocking material from the supplier (DC Fix black velour felt). I also have the 2mm neoprene sheet that I am planning to use for any needed baffling. Once the tube frame is finished (clear coated with spray polyurethane, I will apply the flocking material to the inside of the stuts to stop side stray light reflection into to the focuser or objective. After seeing the original objective in person, I realised I will have to fabricate a collar to mount it to the front plate; I had thought it would slip inside the front plate but it won't and I don't want to machine it (the front plate) any thinner and a collar will add strength and allow the use of the collimation screws (which for some reason iStar do not supply with the objective (guess you have to buy their front plate). I have two options for the objective collar, a solid aluminium collar cut from plate or laminate four 2.5mm sheets of MDF into a plate (this would be epoxy bonded and sealed and could be painted prior to coating to mimic the ply frame rings).
I have a 10mm plate of aluminium but its going to be much easier to cutout the mdf laminate. If I could machine the aluminium I'd probably go that way. Anyone have a recommendation on cutting 10mm aluminium plate in circles? I have seen the many drill holes technique, which is alot of work.
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