I'm planning on building a rocket using a Rattworks I90 sometime in the near future. I'm designing every aspect prior to building anything, but here's where I've gotten stuck:
What exactly do you do with the vent hole? Looking at photos of the motor, it's just a small hole in the side of the forward closure, but how do you ensure that the escaped nitrous oxide shoots out the side of the rocket instead of freezing the inside of the rocket and causing condensation and water damage? Does it require a tube to go between the motor and the outside? Does it matter if the motor is allowed to rotate?
I'm planning on using it in a 38mm body tube and my self-imposed design constraints (No airframe breaks, potentially removing the entire 29mm motor mount in case I want to fly 38mm motors, the charge needs to be at the bottom of a footlong section of tube right above the motor, I don't want to put wires through shock cords, the wires are coming from the aft end of the rocket forward) are forcing me to design some clever mechanisms for installing charge holders, but without knowing what to do with the vent hole I can't finalize my designs.
In case anyone is wondering, this will be a clustered rocket with an I90 in a 4-foot 38mm tube, boosted by two airstarted 29mm solid motors in nonremovable pods on the sides, with a drogue chute in one pod, a Raven altimeter in the other pod doing the deployment and airstarts, the main parachute above the I90 in the central body tube, and a tracker in the nosecone.
2013 impulse burned: 5205.1 Ns
2013 impulse lined up to burn: ~56,445 Ns