On Sep 27, 7:57 pm, Eric in North TX wrote:
I'm planing on applying 12" X 12" granite tiles to the front surfaces
of a steel fireplace insert.
It has bee suggested I use mesh attached to the sheet metal with
screws and use mastic. The person who suggested this said the trick
wasn't getting them to stick, the trick was getting them to stick for
20 years, and I agree. I'd prefer not to have to deal with the added
thickness of the mesh. I had a thought; perf the sheet metal with a
drill to give the the mastic something to grip. Any thoughts on this

it won't stick well, or at all. if it does, then the flexing of the
steel (either pushing against it) or from heat expansion, the tiles
will pop off or the grout will crack anyway.

attach cement board in front of it, then thinset the tiles to that.