Estes Great Goblin, #9724 Build, Part 24, Engine Retainer

I used 220 grit to roughen up the inside are of the engine retainer ring.

I'm always tempted to apply epoxy to the inside of the plastic ring - but - 

If you apply the glue to the outside of the motor mount tube you won't see or have to deal with epoxy squeezing out when the ring is pressed in place.

Push on the ring and turn it to spread out and even the epoxy glue.

I was curious before the ring was glued on -

The rocket rests on the trailing fin tips. There is some clearance under the retainer ring.

Here's my three Goblins - 

The original BT-55, D engine model is on the right.

On the left is a new Great Goblin almost ready for the decals.