Which adhesive caulk for solar panel mounts??
My CW has Sikaflex in 221, 505 and 715. Which one is best to mount solar mounts to thin fiberglass roof along with screws?
Forum Discussion
Almot wrote:
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According to my friends who used 5200, it's hard to remove, much harder than 4200.
4200 not only cures soft-ish but also cures very slow. It has low density and flows out on sloped surfaces, don't expect it to behave like a usual caulk.
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I would definitely use 3M 5200 if that was the only thing holding the brackets down, especially as others have had success with this on fibreglass. And as also mentioned, 3M adhesive tapes may be strong enough.
But as my brackets used 3 screws each, 4200 has worked well so far with no apparent UV deterioration after 3 years. It did take a day or so to cure and is not rock hard. But I see the new brochure lists it as "4200FC" which must imply "fast-cure". Pretty sure the stuff I used did not have the FC.
If no adhesive properties are needed, just sealant, I've use both Dicor and Geocell, and other polyurethane sealants with good results.
