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How to Make a Model Rocket Motor Mount

When the Soviet Union launched its first Sputnik satellite in 1957, Americans were awed, and a little afraid. The race into space was on. Almost immediately, kids began building their own model rockets in the backyard, oftentimes with disastrous results. The need for safer rockets gave birth to the model rocket hobby, which still thrives today. These models are constructed with cardboard, balsa wood and plastic and powered by pre-manufactured black-powder engines, which can take them hundreds, even thousands, of feet into the air. These engines, about the size of flashlight batteries, are mounted in the rear of the model with motor mount--a small tube with centering rings. They sometimes utilize an engine hook, a small strip of metal that helps hold the engine in place. Today, model rocket tubes and engine mounts come in industry-standard sizes.

Things You'll Need

Engine tube
Engine hook
Centering rings, 2
Engine block
Kevlar shock cord
Ruler
Exacto knife
Pencil
Rocket engine
White glue
Paper towels

Instructions

- 1
  Mark the body tube with you pencil. You should mark it about 1 inch from one end, but this number will depend upon your rocket engine and mount size. Cut a small hole at the mark with your Exacto knife so you can place the end of the engine hook through the small hole. Make a second line on the bottom of the rocket, equal distance from the opposite end as the first mark was. Slightly bend your engine hook, to make it malleable. The other end of engine hook should go beyond the end of the engine tube by about a half-inch.
- 2
  Slide one centering ring down over the engine mount so it holds down the engine hook. Cut a small notch in the other centering ring so you can place the shock cord through the notch on the inside of the centering ring. This allows the centering ring to lie flat against the engine tube while the shock cord is within it. Slide second centering ring on engine tube. (Note: The shock cord will later be pulled up through the rocket's body tube and attached to the nose cone to assist with parachute deployment.)
- 3
  Tie the shock cord onto center of engine tube. Pull cord tight against centering ring and engine tube. Place glue around the outside edge of the engine tube and slide the centering ring (with shock cord) over the glue so the ring is glued firmly down to the edge of engine tube. Glue down the excess shock cord on the outside of engine tube (you don't need much glue for this). Wipe-off excess glue. On the second line you made with your pencil, place a dab of glue and slide the other centering ring over that dab of glue so it will be held firmly in place.
- 4
  Rub glue on the inside of the engine tube (all the way around) just above where the engine hook protrudes into the engine tube. Place the engine mount on top of the glue so it is resting against the engine hook. You can use a rocket engine to slightly push up against the engine block to make sure it is even within the engine tube.
- 5
  Pull the shock cord through the interior of the engine tube and out the other side so it is alongside the free-hanging engine hook. This allows you to glue the finished engine tube inside the rocket tube.
- 6
  Place glue a few inches inside the rocket tube so the front of the engine tube will be glued into the rocket tube; glue the lower section of the engine tube (where the shock cord and hook are) so the rear section of the engine mount is glued down-this ensures both the front and back of the engine mount are properly glued into the main tube. The engine tube should hang out about 1/4 inch outside the base of the rocket. Engine mount is complete.

Aviation