Concrete Smoother tools

Wet Polishers for Concrete Countertops
Time: 06:01
See how wet polishers and pads are used on concrete countertops.

It’s often desirable to polish the surface and edges of a concrete countertop to create a smoother, more aesthetically pleasing finish. In addition to giving your countertops an attractive sheen and exposing some of the aggregate or decorative add-ins, polishing will also remove small blemishes and flaws resulting from the casting process.

Tools Required

• A variable-speed (500 to 3, 000 rpm) hand-held wet concrete polisher equipped with a built-in water feed and GFCI shutoff.
• A set of diamond grinding pads, with grit levels ranging from coarse to fine. Both Buddy Rhodes and Jeff Girard use diamond pads with grit numbers ranging from 50 to 3, 000. The more aggressive, coarser grits work best at exposing aggregates and removing blemishes. Youll use the finer grits for final polishing, progressing to higher grit levels until you achieve the desired surface sheen and smoothness.
• A large squeegee.
• Safety goggles and ear plugs.
• Hand-held diamond blocks or pads for polishing areas of the countertop that can’t be reached by the electric polisher.

Buying tips: A grinder/polisher with an attached water feed for wet grinding will help to reduce dust and extend the working life of the pads. Girard uses a grinder with an operating speed of 4, 000 rpm. Since youll be switching pads frequently, also ask if the mounting system on the grinder permits fast changeovers.

Using a small wet grinder. Countertop Institute in Raleigh, NC

Hand finishing pads. Concrete Countertop Institute in Raleigh, NC

And dont neglect the obvious: Be sure to buy diamond pads suitable for use with your grinder and specifically designed for grinding concrete, not granite. Concrete has rough, hard aggregate in a relatively soft matrix. Granite is uniformly hard. If you use pads designed for granite, they will not last as long or work as effectively, says Girard. Sources for concrete grinding and polishing tools and accessories include, , and .

Polishing Steps

Step 1: Clean the fully cured concrete countertop by running water over the surface and then going over it with a squeegee to remove any grit that could gouge the concrete as you grind it.

Step 2: If you notice minor flaws or tiny bugholes, be ready to fill these voids with a patching slurry prior to polishing. Slurries can be color-matched to the countertop or in a contrasting hue to create veining. You can mix up the slurry yourself using a combination of cement, fine sand, water, and pigment. But for greater convenience, consider buying a ready-to-use prepackaged slurry, which is often sold by the suppliers of countertop mixes. Be sure to get a product compatible with the mix you're using. Some are available in various pigments.

Step 3: Start by polishing with the coarsest pad (typically 50 grit), depending on the desired finish. Go over the entire surface, including the edges, making sure to supply a constant stream of water to the surface as you grind. Keep the polisher level as you go.