- Jul 21, 2014
- Reaction score
Seems like a contiguous G12 tube is overkill and could be a good location to shed some weight particularly in rockets where motor ejection was not used.
Certainly, holes are just easy.On something like G10 or other composites, you can machine something other than a circle into them, and a square or trapezoid eats up more area, thus removing more weight, so don't waste too much time with drilling lots of tiny holes.
Just go flying case at that point. Or glue the fins directly to the motor case.Hmmm, joker amongst us :wink: Then how about this Anyone drill holes in their G12 motor tubes or minimum diameter body tubes to reduce the mass of their fin cans?
This isn't a joke. Size the centering rings to fit the motor, and you don't need a motor mount tube.
This sounds perfectly reasonable if you decide up front to use a certain length case and spacers when you need to use a shorter reload.I have said it before- skip the motor mount tube. Have centering rings I.D. sized to match the motor. Have fun tabs longer to reach motor. Pretty sure this will work.
My school did the "no mmt tube" last year for a project rocket we flew. The only issue was figuring out the thrust ring at the aft end; we ended up with 2 extra centering rings, one of which we mounted the retainer structure to. The other was put in place 2" shorter than the smallest motor we planned to use. Worked well for us, but there is a drawback. If you use adhesives to mount fins, it is possible to compromise that joint when the motor heats up during flight. If using that method, I'd recommend building a fin box for each TTW and mounting them to the CR's. If you're bolting everything together, shouldn't be a problem (that's what we did).I have said it before- skip the motor mount tube. Have centering rings I.D. sized to match the motor. Have fun tabs longer to reach motor. Pretty sure this will work.