Originally Posted by
serious power
Hi,
Just a little on method for applying the skins.
- Using the veil on the inside eliminates the need for additional structure ; spars, carbon straps etc.
- I dispense the PU with a syringe and a lab,, calibrated sampling nozzle. This measures that used and I cut the tip back on the nozzle to give the desired bead size.
- I roll a 'damp' emulsion roller across the core before applying the glue bead. I then roll it over the skin/carbon veil just before positioning it. I do not wet anything - just leave a residue.
- Using PU on pre-sealed surfaces means that one skin can be applied at a time as there is no wetting of the wood. This makes accurate alignment easier as it is critical for the application of the 2nd skin only.
Brian
Hi Brian,
I saw the beautiful job you are doing here and was struggling with myself if I should tell you what I am going to tell you now:
About 20 years ago I built a plane named Vortex with wings structure about the same as you are building here.
That plane crashed in it fourthly flight!!!
The wing had broken in the air about were the aileron servo was.
As I analyzed what happened: in positive G force the lower skin is pushing against the foam and the upper skin is try to disconnect from the foam.
As a result of the lake of foam area the foam itself could not held the tension forces.
Just a sad story.
Good luck,
Isaac Najary