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Old 16-01-2014, 11:13 PM
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barx1963 (Malcolm)
Bright the hawk's flight

barx1963 is offline
 
Join Date: Nov 2008
Location: Mt Duneed Vic
Posts: 3,982
A collimation cap has one purpose only, to allow the eye to be centred in the focuser. No matter how hard you try it is nearly impossible to accuratey centre the eye over the focuser tube.
Easy way to make one is find somewhere local than sells camera film (remember that stuff!!) and take the film and throw it away (unless you can use it of course) then remove the lid from the canister, throw that away and then use a drill to put a small hole in the base of the canister. There is your collimation cap.
With regard to the angle of the support for the secondary, that is completely irrelevant to the ability to collimate the secondary. The secondary holder should rotate so you can adjust the secondary and the only important thing with the secondary stalk is that the centre of the holder is in the middle of the tube. simply measure the distance from the centre of the holder (there should be a screw head there) to the edge of the tube and if it is the same in say three different directions, that is fine. If it is out, there is not much that can be done with a simple stalk structure, personally I wouldn't fuss about it too much unless it is out inches!
I am not sure why you cannot see the secondary screws? They are clearly visible in the pic post 5 on the SGL thread you inked to. Does your scope look anything like that?

Malcolm
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