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:
3M 4200 is a sealant, it cures somewhat soft. Adhesion, particularly to FG, is a different matter, not everything adheres well to cured polyester resin but this is not crucial when sealant is used to seal rather than to hold.
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Yes, 3M 5200 is a stronger adhesive, but both 4200 and 5200 are
referred to as "adhesive sealants" in 3M's brochures. 4200 in particular is described as an "excellent adhesive sealant".
multimedia.3m.com/mws/media/811831O/3mtm-adhesive-sealant-brochure.pdf
The brochure has a comparison of their adhesive properties.
3M also markets 540 polyurethane and 730-755 hybrid products that they only refer to as "sealants", not "adhesive sealants". I suspect these are more similar to Geocell and Dicor sealants.
As both 3M 5200 and 4200 are marketed for the marine market, I'm sure they adhere well to fibreglass.
