Filament-Wound Fiberglass airframes

[bobby_hamill]

I wish the manufactures of Filament-Wound Fiberglass airframes
would give the inside and outside diameters
as well as wall thickness to help in rocket scratch building !!

Bobby

[dixontj93060]

I use this reference document: http://www.performancerocketry.com/a...gapril2011.pdf

[jd2cylman]

I would like to believe that this document is correct, but unfortunately, material on hand begs to differ. I have in my possession one piece of PR G10 airframe and one piece of G12 airframe. ID's are the same, but OD of the G12 is slightly larger (my digital caliper stops at 6", so I can't give exact OD). I also have a G12 coupler and a G10 coupler with bulkheads. The bulkheads will not fit into the G12 coupler. So, although the chart says they are the same thickness, (at least on the 8" airframes), my on hand materials do not bear this out. Not tryin to start a fight, just sayin.......... Which also begs the question, what should I do with this rocket? The upper 48" is G12 and the lower 48" is G10. So there is a slight step down to the G10. The lazy builder in me will probably just sand the edge enough to make the difference less obvious. The super lazy builder in me will probably just build the thing as is; what step?

Adrian

[north boy]

The lazy builder in me will probably just sand the edge enough to make the difference less obvious. The super lazy builder in me will probably just build the thing as is; what step?

Adrian

you sound like me lol

[troj]

Part of the difference you're seeing is that the mandrels used are tapered, to facilitate removing the layup from the mandrel. After winding, the ground down, the accuracy of which can affect dimensions.

Keep in mind we're paying for hobby grade materials. While it's possible for high tolerance manufacturing, you likely wouldn't want to pay for it.

In the materials I've worked with that were made by Performance, I've noticed the greatest disparity in the 6" tube.

-Kevin

[bobby_hamill]

here is what I have found thus far

performance rocketry

6" = 6.040 inside diameter x 6.210 outside diameter x wall .085 = g12
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Hawk mountain

6" = 6.00 inside diameter x 6.148 outside diameter x wall .074 = g12 weight = .9 pounds per foot

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Giant leap

unknown

then you have g 12 and g 10 how can you tell the difference ?

weight per foot would be nice to

[CarVac]

You can tell by looking: G10 is made from cloth so you can see some circumferential fibers and some longitudinal fibers. G12 is made of diagonal fibers.

[bobby_hamill]

thanks on the difference details.