"Stop Drilling In Composit Material"

[Smilin_Ed]

"Stop drilling" can sometimes be used as a temporary fix to stop the progression of cracks in metallic structures. Does anyone here know if stop drilling is effective in composite material?

[WillDAQ]

Drilling any hole into a laminar composite structure is a Very Bad Idea™. In all likelihood, worse than the crack.

[Genghis the Engineer]

I agree with Will.

The crack formation and propogation mechanism in composites is totally different to that in metals. All drilling will do is create new problems.

Properly authorised composite repairs will be needed, and quite possibly simply replacement of the component.

FAA's AC43-13 should contain some useful guidance on the topic. Try chapter 3 (http://rgl.faa.gov/REGULATORY_AND_GUIDANCE_LIBRARY/RGADVISORYCIRCULAR.NSF/0/99c827db9baac81b86256b4500596c4e/$FILE/Chapter%2003.pdf); this gives guidance on stop drilling acrylics (perspex for example) but shows quite different approaches for laid up composites.

G

[Smilin_Ed]

Thanks to both of you. You have answered my question.

Ed :)