Building the
Atom Minor Mk III

by Jan Huning

7. Propellor Hub

The propdriver collet was machined at one setting, as described in ETW's book. I used 1/8" BSP for the thread. This is only 8 thou bigger diameter than 3/8", has a fine pitch (28 TPI), and more to the point, I had a suitable tap. I think it was machined from EN16M.

The cam surface on the back of the propdriver was machined by holding it in a 3-jaw mounted off-centre on the rotary table.

 

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