Using 80 grit sandpaper will penetrate the surface enough to open the pours on the wood so it will absorb more glue.
Best way to glue granite to wood.
Wipe the bottom side of the stones with a damp cloth to remove any dust or dirt.
Use an etching primer on bare metal or a bonding primer on previously painted metal.
A two component epoxy glue was really the only option available to stick granite but this was far from perfect.
Step 2 scuff the wood gently with a piece of fine grit sandpaper on the area to which you intend to glue.
And enable the primer to dry out for the manufacturer s prescribed period of time.
They all agree that the best choice would be a polyurethane construction adhesive such as.
Epoxy glue is the most common type of glue used in granite installations as it is one of the few types of adhesives that can provide a bond that is as strong as the stone itself.
Keep the spray gun about 1 foot from the surface and use quick spreading movements to spray a primer coat.
They have to be manually mixed and if the correct mix is not achieved the bond will fail.
Some reliable polyurethane adhesives are gorilla glue and titebond which both host the ability to join these two materials.
Wipe them dry with a paper towel and allow the stones to air dry completely.
These type of adhesives are very dated in their technology.