More Body Tube Sizes?

[pcotcher]

I'm working on scaling dimensions for a few different scale projects and find myself wanting for more tube sizes. Particularly in the larger range - can anyone recommend other tube manufacturers that do larger sized tubes (3" +) that aren't the standard LOC or PML sizes? Something in the 5.25" range would be PERFECT. I know there's the LOC 5.540" tube, but that's a bit large.

The smaller tubes (with all the sizes that SEMROC offers) fill just about every gap, but then, once you clear 3", the sizes drop off significantly.

A couple more in the 4" range would be good as well!

Ah, the plight of larger scale rockets!

Thanks!

 

[powderburner]

To entice any of the body tube manufacturers to make your new size you are going to have to order quite a few. That's the usual barrier to starting up a new body tube diameter.

You could make your own. Find some mandrel material (PVC pipes, tubes manufactured for other uses, or have a wooden cylinder custom lathed and soak it with epoxy, etc) and use some kraft paper to spiral roll and glue. Hey, it's been done before.

 

[Stymye]

you can always take the LOC tube and cut a slit from it to get the right diameter, glue the sliced off piece inside and slightly notch the centering rings to clear.

not a hard operation on that size tube

 

[TheAviator]

To entice any of the body tube manufacturers to make your new size you are going to have to order quite a few. That's the usual barrier to starting up a new body tube diameter.

You could make your own. Find some mandrel material (PVC pipes, tubes manufactured for other uses, or have a wooden cylinder custom lathed and soak it with epoxy, etc) and use some kraft paper to spiral roll and glue. Hey, it's been done before.

Could you expound upon this technique, PB? I'm interested in this for making scale tubes.

 

[luke strawwalker]

John Pursley has had EXCELLENT results rolling his own tubes from 1/64 light plywood. I've seen these tubes and they are AMAZING-- strong yet EXTREMELY light! He rolls them in whatever custom size he needs, all the way down to about a BT-80-- below that the curvature gets so tight you have to take special precautions to prevent the plywood from splitting.

He makes "stiffener rings" for the interal part of the tubes by overlapping "biscuits" of plywood (small 'lemon wedge' shaped pieces overlapping and glued to each other to form a ring with a "hexagonal" internal hole) The "hexagonal" (ok shape despends on how many "biscuits" you use) hole is not much smaller than the interior diameter of the tube itself-- meaning the ring is very thin with a large hole in the center, so they add very little weight. Traditional centering rings can be cut from plywood sheet similar to any other centering rings.

For more info, check his website at accur8.com or contact him over there.

Later! OL JR