I wasn’t able to use vinyl product in the confined space of the fire box.
Cement board, used Trim-Tex 3/4 arch to cast sheetrock 90 covered with saran wrap. Trim-Tex 3/4 bull, l bead, adapters, 3/4 radius j bull, double layer drywall.
Heavy coated whole surface for scribe, used 80 grit to purposely leave circular sanding marks on the surface.
Posted in Fireplaces, Trim-Tex