Monday, February 8, 2016

Estes Quinstar #7241 Build, Part 9, Removeable 18mm Mount



The 24mm BT-50 tube and ring are glued into the center hole of the cage.
Glue was dripped down the side walls and the tube slipped into place with the centering ring (engine block) at the top.




Glue together the 18mm mount as shown in the instructions but the top 20/50 ring is left off. That ring is already inside the BT-50 now in the cage.

A rubber band was used to keep the split ring ends down and against the body tube wile the glue dried.


The open top of the BT-20 mount slides into the 10/50 centering ring at the top of the BT-50.
I had to rub down the burrs on the inside of the centering ring so the top of the BT-20 tube would slip in easier.




Here's the 18mm mount in the 24mm tube. It's not glued in, but slipped into the 20/50 ring already in the top of the BT-50 tube.
The rear notched ring is flush with the end of the BT-50 tube.

A small strip of tape would wrapped around the back end to keep it in place. The fit is pretty tight, it might not even need the tape.
The ejection charge would blow out the top, it might not kick out the engine mount.

2 comments:

  1. Just a stupid question -- what is keeping the 18mm motor mount from sliding up into the 24mm tube?

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    Replies
    1. Hi Naoto,
      The upper bend of the engine hook is butted up against the inside edge of the 20/50 ring at the top of the BT-50 tube.
      The thickness of the engine hook is enough to hold it in place. The fit is tight and with the engine hook wedged against the ring it won't go anywhere. With a C engine, the rocket will move up before the engine mount tube will.

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