I maybe should state that I’m gluing this up with epoxy and internal fillets because I feel like it, not because it’ll necessarily need it. I doubt I’ll go higher than a G in it. Then again, I’ve never flown the Ventris on more than a G and I’m repairing its second popped fin… maybe it will need it.
So here’s the motor mount with the front ring epoxied on and another ring dry fit. There’s a Kevlar shock cord leader tied around the motor mount (through a hole I drilled a little late in the game) and another piece of Kevlar tied in front of the loose ring. I put epoxy inside the body tube near the front of the fin slots and stuck the motor mount in. (Note: The slot lengths shown on the template are a little longer than the fin tabs. I positioned the motor mount so the front centering ring was visible through the slots, leaving a gap just big enough for the fin tabs.) The shock cord leader was fed through the motor mount to keep it out of the epoxy, and the other piece of Kevlar was caught between the loose centering ring and the airframe. Dry fit of the stack before gluing the motor mount.
Once the epoxy was cured I pulled off the loose ring using the Kevlar, and fed the shock cord leader back up into the body tube, then started gluing fins.