View Single Post
  #4  
Old October 29th 07, 01:34 AM posted to rec.aviation.homebuilt
[email protected]
external usenet poster
 
Posts: 28
Default Something to measure physical pressure.

For the fuselage, I'd stick with either aircraft or marine grade ply
for glue strength between plies.
If it's all flat areas, then 90 deg. layups are going to be the least
expensive and should work fine. If there are curves
then you are probably going to be limited to using aircraft grade with
45 deg layups. Do the
prints give you any guidence on thicknesses to use for the various
areas? If so, then there are
tables out there that give the various strength data vs the number of
plies vs the ply materials. They
also give the testing method used to generate the data. For fabric,
the Maule tester is the accepted
method. Ply is done by tension and twist test if I remember correctly,
coupled with steam testing of
the bonding agent. Composite is done by tension, compression and
impact tests. Tension and
compression tests are reasonable easy to duplicate, impact can be done
too, but is most likely
going to be a bit more subjective without a decent lab setup.

When in doubt, talk with the designer is the best advice. Unless there
is a complete egineering
workup with the design, that's about the only way to know why the
particular material selections.

Food for thought...

Craig C.