Do you want to polish your concrete countertops, table tops, or other concrete surface to a high sheen? The free 2-hour seminar below explains in depth everything you need to know to grind and polish concrete countertops successfully, including what diamond pads to use, how to use a polisher and what densifiers actually do.
BUT… before you embark on polishing concrete countertops, be sure to understand what your plan is for protecting those countertops from staining and acid etching.
Polishing does NOT provide protection from staining and etching. It merely makes the surface shiny and very smooth, so much so that liquids bead up. However, those liquids are still physically touching bare concrete, so they WILL stain/etch.
If you want to protect the concrete from staining/etching, you need to seal it with a coating, such as a high performance urethane such as Omega Concrete Countertop Sealer. Coating sealers will not stick to polished concrete. In fact, we recommend that you stop processing at 200 grit before applying any coating sealer.
When you are using a coating sealer, the sealer is what determines the sheen of the finished piece. There is no need to do a lot of work polishing the concrete itself to the desired sheen.
If You Still Want to Polish to a High Sheen
If you do want to create a polished concrete surface to which you will apply only a penetrating treatment or densifer, here are some tips from the video:
You will start with either a turbo cup if you want to expose aggregate, then grout as appropriate to fill pinholes. Then you will start the grit progression from 50 grit all the way to 3000.
If you are using a densifer, it is often applied after honing, at grit 200. The densifier makes the cement paste hard so that it can be polished. Once the densifier takes effect, polishing proceeds from the 400 grit onwards. The length of time for the densifier to take effect depends on the type of densifier. Some lithium densifiers start to work right away.
Do not skip grits. Each grit in the progression is designed to smooth out scratches from the previous grit. A 3000 grit pad is incapable of smoothing out scratches from a 200 grit pad, no matter how long you grind.