Foolproof?  Stress it to 8 g’s and fly it below 4 g’s.

Not so foolproof….Quarter drop test.  Take a quarter and hold it between your thumb and forefinger from about 3-4 inches above your target.  Drop it on the composite surface.  If it bounces the bond joint is OK. If it doesn’t bounce as well, there is a  poor bond or delamination.  Once you get the hang of it you can drop and catch the quarter repeatedly and quickly.  You will be able to identify where ribs are using this technique. Follow a rib looking for a  poor bond.

Craig Berland

N7VG

Does anyone know of foolproof tests to determine whether a composite has suffered impact or thermal damage?

Mikell Becker