13mm fiberglass tube

The Rocketry Forum

Help Support The Rocketry Forum:

David Schwantz

Well-Known Member
Joined
Jul 23, 2018
Messages
1,418
Reaction score
522
Location
MN
Does anyone have them available? Checked, Wildman. Madcow, Mach 1.
 

heada

Well-Known Member
Joined
Jan 18, 2009
Messages
3,200
Reaction score
559
Location
Indianapolis, Indiana
13mm is just a hair over 1/2" (0.512 vs 0.500) so 5/8" is the next size up (0.625) so you'd have to add tape to the 13mm motor to build it up to 5/8" thickness. https://www.mcmaster.com/2197k11 that'll get ya 5/8" ID with 1/16" wall thickness. Less than $9 for 3 ft.
 

SDramstad

Well-Known Member
Joined
Jun 26, 2014
Messages
585
Reaction score
428
Dont know if a 13mm motor would lift that....
 

heada

Well-Known Member
Joined
Jan 18, 2009
Messages
3,200
Reaction score
559
Location
Indianapolis, Indiana
I doubt it would lift the entire 3ft but it *might* lift 6in of it. I think CF might be a better option at this size due to the weight. Closest I can find in CF is 3/4" ID at $25/ft that would work for 18mm. Or you know.....cardboard tubes.
 

cerving

Owner, Eggtimer Rocketry
TRF Sponsor
TRF Supporter
Joined
Feb 3, 2012
Messages
3,653
Reaction score
889
The FG tubes that are used in FAI competitions are hand-rolled over a mandrel. Not a commercial item AFAIK.
 

David Schwantz

Well-Known Member
Joined
Jul 23, 2018
Messages
1,418
Reaction score
522
Location
MN
Thanks for the replies, I am doing a 13mm MD project. I made it in cardboard already, but would like glass instead.
 

georgegassaway

Lifetime Supporter
TRF Lifetime Supporter
Joined
Jan 18, 2009
Messages
4,543
Reaction score
376
"MD project"?

If you need more strength/stiffness but increasing the diameter and mass a bit would be OK, you could consider wrapping 3/4 oz glass cloth around a paper 13mm tube, using a good quality epoxy resin. Just I can't tell from your posts what the specific need is for a fiberglass tube.

Worst-case, 13mm drill rod could be used as a mandrel for making an all fiberglass tube. After a good coating with spray on mold release before layup, the ID of the resulting tube should work for holding a 13mm engine.
 

caveduck

semi old rocketeer
Joined
Jun 6, 2011
Messages
1,403
Reaction score
131
Having personally made all-glass competition tubes, I can vouch that it's a certain amount of work. Usually you do it to *reduce* mass - 3 wraps of 0.7 oz cloth will end up at around 1/2 the mass of a paper tube but it's pretty fragile and bendy. You can use more wraps or heavier cloth to get a sturdier tube, or just glass over a paper tube like George said. You'll get a stronger tube doing that if you peel off the glassine layer first (if there is one).
 

prfesser

Lifetime Supporter
TRF Lifetime Supporter
Joined
May 7, 2017
Messages
1,172
Reaction score
1,005
Location
Murray, KY
FWIW check swj3-90 on eBay, has 13 mm i.d., 0.5 mm wall carbon fiber tubing, $18 for 1 m.

Best -- Terry
 
Top