Might be a dumb ?

[kandsrockets]

I have a upscaled Der Red Max that was built for a 29mm hobby RMS but now I would like to use 29/240 case in it but the casing is longer than the motor tube. Will this be a problem? The motor case will be about 2" longer than the motor tube is.

Thanks
Scott

 

[rstaff3]

There is nothing generically that keeps you from doing this, and I have done so on other rockets (my NCR Big Brute is one example). A couple of inches shouldn't make a lot of difference, however, you should verify stability in case you are already on the edge and think through motor retention.

 

[DJDeadParrot]

The only other issue I can think of is if parts of your recovery system [shock cord, parachute lines, etc] come in direct contact with the hot motor casing. I'd say pile in enough wadding to bury the top of the motor.

 

[hokkyokusei]

No problem. I have several rockets that I fly like this.

 

[jj94]

If you're worried about the excess heat from the bare motor, you can make a small fitting to cover the end of the motor. Take an appropriately sized coupler and glue a proper centering ring onto the end of the coupler (in this case, a 3"-1.14" CR). Do the same to the other end, and then glue in a 29mm motor tube (the same length as the coupler) inside the CR's. Then take the fitting and slide it over the top of the motor once it's installed. If you want to, you can apply some tape right above the fitting to make a block so the fitting won't slide out. Just an idea.

 

[rstaff3]

It appears I totally slipped a bit on this one. My mind thought you meant hanging out the back end by 2"....because hanging out above has been soooo common for me. Either way - hanging out above or below can work. Same comment on stability applies. I've seen people build rockets with no motor tube - just properly sized rings.

 

[TeenRocketNerd]

Originally posted by DJDeadParrot
The only other issue I can think of is if parts of your recovery system [shock cord, parachute lines, etc] come in direct contact with the hot motor casing. I'd say pile in enough wadding to bury the top of the motor.

just use a nomex heat shield and you won't have to worry about this, krsconstruction.

 

[kandsrockets]

Thanks for the comments all. I am going to throw a hand full or two of dog barf in first then put my nomex blanket, chute and harness in.

Stability has already been checked before I even asked this question and is good to go.

Again thanks.

 

[jraice]

With some rockets it sticks out much more, 2"s is fine...

For example the competitor 4's motor mount is only 2', but people put 30-40 inch motors in there all the time...