38mm Motor Retention (Friction Fitting) techniques?

Hello guys! Though I've been reading a lot of your post's and have been around this forum for a few months now, I've finally taken the initiative to make an account and post a new thread of my own. So here's whats going on;

I'm competing in a MAX altitude hybrid rocket competition here next month and I'm currently considering friction fitting my hybrid motor. Our rocket will be putting out just under 160NS of impulse, so a G-class motor. I've heard a lot of people say they've had great success with friction fitting their motor! Here's my issue; I've never friction fit a motor before (so i have no idea how besides reading examples from apogee's newsletter). I've considered a slimline motor retainer but it protrudes from the air frame thus affecting its aerodynamics. So, do you guys know of any special techniques that would insure my motor isn't ejected during flight/takeoff? shall i use aluminum and masking tape? And of course, it needs to come out of the air-frame as well (i've heard story's of adding too much masking tape and its effects). If you guys have any pictures or know of any videos/guides that are available that would help tremendously!

-Gligur

I think a simple wrap of aluminum tape over the airframe and motor should do it.

markkoelsch said:

I think a simple wrap of aluminum tape over the airframe and motor should do it.

Click to expand...

This.

The tape on the outside of the motor tube is more important than the all the tape crammed inside the motor tube

In addition to the technique (as mentioned above), there is verification. Take a fish weighing scale and attach a clamp or some other means of affixing it to the end of motor. Then pull apart from the NC. This will tell you the minimum force to pop open your rocket. Then while holding onto the booster frame, pull until the motor starts to slide out. I prefer 2-3 times the force that it takes to pop open the airframe. This way, if you have an RSO who has doubts, you can..... "BAM!!!!", pull out the numbers and prove your motor will not spit out the end.