Introduction to Diamond Grinding

Diamond Grinding

Diamond grinding is defined as the removal of adhesives, coatings, underlayments or rough concrete through the use of metal bond diamond segments.

Grinding Grits

There are four metal bond diamond grits that are considered ‘grinding’ segments. The four types are 6/12 (very aggressive), 16/20 (somewhat aggressive), 30/40 (aggressive) and 50/60 (least aggressive).

The 6/12 diamond is the most aggressive grit. These segments work well for the removal if some coatings, most adhesives and are very productive on uneven or rough concrete. The profile that is left by a 6/12 diamond is rough. This grid is good for preparation for underlayments, some carpets, thick-mil epoxies and any other finish that will not allow the scratches to telegraph through the finish. The grit is not a suitable size for VCT, thin-mil epoxies and some carpeting. In suitable applications the 6/12 grit is the most productive grit for removal.

The 16/20 diamond is the next finest grit size after the 6/12. These segments work well for the removal of most coatings, adhesives and are somewhat productive on uneven or rough concrete. The profile that is left by a 16/20 diamond is somewhat rough. This grit is good for preparation for underlayments, all carpeting, VCT*, some thin-mil epoxies and most medium to high build epoxies.

The most commonly used grit is 30/40 because it is the most versatile diamond size and can be best described as a ‘general purpose’ diamond. 30/40 grit diamonds are used for the removal of adhesives coating, but do not leave a scratch so deep that will telegraph through the flooring finish (i.e. VCT or thin-mil epoxies). They provide a deep enough scratch so the mechanical bond of epoxies, underlayments or adhesives is sufficient to hold the product(s) to the substrate. The production level of 30/40 may not equal a 6/12 grit, but regardless of the new flooring, the substrate is ready to receive it.

The 50/60 grit diamond is the finest of the grinding stones. It is useful in removing small amounts of sealers, adhesives or generally dirty concrete. The scratches are deep enough to receive and flooring installations, but they will not telegraph through any coatings or flooring.

Metal Bond Polishing Pads

The 80/100 metal bond diamonds are used for smoothing out previous grinding steps, and making the substrate more consistent than a grinding grit. This segment rarely works for removal, and is usually used to start the polishing process. On concrete that has been ground with a 30/40 grit or a 50/60 grit diamond, the 80/100 must be the next step is a polished surface is desired. The 80/100 nay also be useful on new concrete is there are minor surface imperfections such as chatter marks from finishing or very minor unevenness at joint lines.