The Centuri / Semroc Point is a tricky rocket to prep. At ejection the engine is pushed out the back and stays attached to the conical body with a length of elastic.
The engine sits far forward inside the cone body at ignition and boost.
The engine is retained at ejection by a small ring of body tube with a short length of elastic shock cord tied on. Slide it over the low end of the engine. A wrap of tape goes over the low end of the engine and ring.
That elastic tether has to stay out of the engine flame during boost. It is held to the side of the interior wall with a small piece of masking tape.
Before sticking the tape to the cardstock wall, stick it to your pant leg a few times to reduce the adhesion. This will prevent the tape from tearing the interior cardstock when the ejection charge fires.
The engine is far up inside the body and it is difficult to conect the micro clips. The old Centuri instructions suggest using some thin extension wire wrapped around the igniter.
I still have a stash of Quest Q2G2 igniters that are perfect for use in the Point. They have 3" long igniter wire leads.
Quest suggests using the protective plastic sleeve to hold the igniter in the engine nozzle. It helps with the friction fit is you crease the sleeve tip with a fingernail so it fits around the igniter wires.
Here's the back end, the rocket is prepped for flight.
The elastic is out of the engine flame and the Q2G2 is long enough to make the micro clip connection easier.
My Semroc Point has six launches. The rigid chute recovery has worked every time. The rocket is getting a bit banged up, I may have to build another!
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