Binding aluminum to fiberglass

K1ngN0thing

I've mounted some aluminum angle to my roof with 3M VHB tape to keep my panel in place, but I'm not confident in the long-term adhesion and would like to make doubly sure it doesn't land me in a lawsuit down the road. Not looking to drill any more holes than I need to, so that leaves me with epoxy or some adhesive. What's best for bonding these two materials?

BB.

Some suggestions:

http://forum.solar-electric.com/forum/solar-electric-power-wind-power-balance-of-system/pv-installers-forum-nec-wiring-installation/336029-bonding-aluminum-angle-to-fiberglass-roof

-Bill

mike95490

RTV may also work, not real strong, but a large enough patch would work. Never used the tapes before, but auto mfgs are now swearing by it.

Surface Prep is the major issue. Fiberglass gets a sunburned burned layer on it, which has to be sanded off. But you need to de-glaze it anyway with 400 grit emery cloth. Rinse liberally with rubbing alcohol to get all debris and contaminants off. Let dry in sun for half hr.
The Aluminum also needs prep. Depending on if it's raw mill aluminum, polished, anodized, coated, whatever. It's got to be clean too, and de-glazed.
Cleaning and deglaze prep is the way that stuff gets bonded. In my bond certification classes, (NASA structural bonding) people fail the prep all the time, we have to make test coupons of all the materials, and when looking at the failed parts, proper prep shows the substrate material failing and sticking to the epoxy. If prep is poor, the bond fails with shiny patches where it did not stick to the substrate.