Rant: My backyard concrete fire pit is refusing to smooth out

I decided to build a fire pit with a nice finished edge as a weekend thing (sounded simple, right?). But no matter how much I trowel, the surface keeps getting these little pits and lines (like it's fighting me). I mixed the batch by hand, and I think I added too much water too fast (my bad, I know). Now it's setting up weird, and I'm worried the finish will look amateur hour. I've done flatwork for years, but curved surfaces are a whole other beast (who knew?). Just needed to vent to folks who get the struggle.

3 comments

3 Comments

robertc441mo ago

Try a grinding stone instead, sanding won't work well on concrete.

roset341mo ago

Robertc44 is right that grinding works better for major concrete problems, but light sanding can fix small pits after the concrete dries all the way. On my last project, I smoothed driveway edges with 60-grit paper and it handled the roughness fine. A grinder is best for deep flaws, though. What sanding method did you try on your planter box, grant_price72?

grant_price721mo ago

Concrete has a mind of its own sometimes, especially on curves. That too much water too fast thing will get you every time, it makes the finish such a fight. Been there with a planter box, and the pitting drove me nuts. A light sanding once it's fully set might save it, don't stress yet.