How To Sand Concrete Smooth. Allow the surface to thoroughly dry (remember, concrete is porous, so give it a day or two for the best results) and apply a concrete sealer. It had the appearance of old weathered concrete, where mother nature and time had eroded the top to create a light sand finish.
Sand the surface and wash the concrete; Apply a new layer of concrete; The grinder is fitted with sanding papers ranging from 60 grit, which is used to even out concrete floor corners and countertops, to 120 grit, which is used to smooth the concrete into a polished finish.
This is actually how to sand a concrete floor around the house.
You will need to create or purchase a float that will be used to produce the smooth finish. Do not let the slurry dry on the concrete because it will harden in place. While using a screed and darby gives you a roughly smooth surface, floating helps smooth out further imperfections, compact the concrete, and prepare for additional finishing steps. Step 8 vacuum the concrete dust with the shop vacuum.