I've had widgets installed by PO using VHB tape that fell off. They were all on raw
fiberglass or
paint (which failed). But I have found a few good uses.
Cleaning the surface prefectly and waiting for warm
weather are key.
Test mount. I secure the pad for a tiller pilot for a test sail, just to confirm the location. I just used a little and it removed easily.
Hold during cure. I then secure the above pad with Sika 291. But I used one of the VHB dots in the center (hidden) to keep it from sliding off the slope while it cured. Worked fine.
Line Hangers (United Yacht Manufacturing). Holding great, 3 years now.
Winch handle holder. Rigid PVC pipe. I would not use it on soft vinyl (plasticizers).
SNADs. basically stick-on snaps. They seem to hold well, and better than drilling a lot of holes for something low tension, like window covers.
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The bond is about 20 psi forever, 500 psi for shocks, and best if the design does not apply a pealing force (sheer or tension are OK).
Ideas?