The 80-mesh screen I use keeps the sand fine and consistent. That control really helps prevent a piece from feeling too gritty or sharp. Just watch your furnace temp, as the extra material can cause thermal shock if you're not careful.
Yeah, @tessap73, that control over consistency reminds me of sifting flour for baking. You get a smoother batter, just like your fine sand prevents gritty glass. It's funny how many hobbies boil down to watching the tiny details to avoid big messes. Your furnace temp warning is key because skipping it ruins everything.
Wow, that whole sand grit talk just made me remember sanding wood projects. You get obsessed with the tiny scratches left by each grit level, and it ends up deciding the whole feel of the finished piece. Guess it's the same kind of fussy detail work.