caulking material ?? Arthur Edmunds

Dont know about sheer clamps, but for joints that must be waterproof and not made permanent with adhesive , 3m strip caulk is used .

Its nice and clean to work with. Because of its density, only use it for joints were you can develope substantial clamping pressue.

I prefer the gray 3M strip caulk

http://3mcollision.com/3m-strip-calk-08578-black.html

 

3M-8578 (Strip Caulk) is butyl rubber. It doesn't have the elongation of the polyurethanes (not even close), but I've seen butyl seals, gaskets, etc. after 30 - 40 years of use, still pliable. If you don't have much movement it's a fine way of doing it.