I used a router and trammel to cut a piece of MDF the size of the spinner back plate. Then I used 1/2" ID nylon spacers from the hardware store to locate the disk at the correct distance from the prop flange.
Does the same thing as the jig that they rent. The problem with the jig, when I was doing this, was that it was for Van's 13" spinner...the Showplanes cowl requires a 15" spinner. (I used an MT prop and the spinner blueprint says the actual spinner is slightly less that 15". I called Showplanes to verify)
Aerospace Engineer '88
Structure - 90% Done
Cabin Top - Aaarrghhh...
EFII System 32 - Done
290 HP Barrett Hung
ShowPlanes Cowl with Skybolts Fitted - Beautiful
Dues Paid 2018,...Thanks DR+