Corian, granite and cambria are strong countertop substances that lend themselves well to work with with undermount sinks. Fasteners held with epoxy adhesive protected this type of sink — which is often stainless steel — to the bottom of the countertop. The counter material has to be dry and dust-free for the adhesive to hold.
Prior to gluing each fastener, you have to prepare the countertop stuff by roughing a patch for it using a handheld grinder along with a diamond-cup wheel attachment or even with medium-grit sandpaper. This removes naturally occurring oils that interfere with adhesive adhesion. You should also heat porous substances, such as granite, with a propane torch or heat gun to melt and evaporate internal moisture. Finally, wipe the stain with a rag moistened with denatured alcohol or acetone to remove dust.
Gluing the Fastener
Glue each fastener with a two-part epoxy product — even when the sink manufacturer recommends a specific product, use it. Mix the epoxy in line with the instructions, or load it at a dispensing gun, and implement enough to the stain to cover it entirely. Immediately put the fastener gently at the adhesive and push until adhesive begins to ooze out of the holes in the base plate. After smoothing out the adhesive with a plastic putty knife, let it set for the recommended period before applying force to the fastener.