Secondary mirror cage
Also in March, I got Baltic Birch plywood through a local cabinet maker. Router was used to cut rings which were then assembled with sections of 1.25 inch tubing and focuser board to form the structure shown below. It was later reinforced with black plastic (Silly Carpet) sheet.
Still in March, I have built Crayford focuser using hacksaw, router and drill press.
Same tools were utilized to construct secondary mirror holder (shown below in pieces) and spider assembly made out of saw blades:
Once secondary holder was assembled in early April and the secondary mirror was glued to it with three blobs of silicon adhesive:
In June Doug cast aluminum pole seats and they were attached to the bottom of the secondary cage. Spider, secondary holder assembly, focuser and large handle were attached as well. I have modified pin-wedge design so they can be stored attached to the bottom ring. This eliminated the need for tiny Coulter pins, too.
Dust covers were made out of thin plywood to close both ends of the secondary cage. The whole assembly can be stored on top of the primary mirror box (with its own dust cover in place as well) - pole seats fit over four protrusions made of hockey pucks cut in half!
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© Jan Wisniewski