Brian's House Building Blog

Tips for Polishing Concrete With a Floor Grinder

by Peyton Sanders

If you have concrete floors that have been looking a bit dull, it might be time to polish them. Concrete grinders allow you to remove the top layer of the concrete slab in order to be smoothed and polished. Here are some tips for polishing your concrete floor with the help of a concrete grinder.

Use Sand for Abrasion

Concrete grinders work great on their own to polish your concrete floor, but if it needs a little more help removing the top layer and polishing it smooth, you may want to add a little more abrasion in the form of sand. If your kids have a sandbox in the backyard, or you have leftover sand from a previous home project, that's really all you need. All you need to do is lay down some sand on the concrete floor, then use the grinder right on top of it. It works the same way as when you are smoothing your skin with an abrasive cleanser.

Pre-Soak the Concrete Slab

Another tip that can help your concrete grinding process go more smoothly is by pre-soaking the concrete. This is especially important with concrete that is outside, such as if you are polishing a concrete driveway or a patio in your backyard. This concrete reaches very high temperatures in the hot months, which makes it more difficult for the diamond tools of the concrete grinder to work effectively. A better option is to pre-soak the concrete with water, which is going to bring down the temperature and allow the grinder to work much better.

Use the Right Rotation Direction

Some floor grinders are made for a lot of different uses, with grinding concrete being just one use. In this case, you might have a multi-directional grinder. If you are using this type of grinding machine to polish concrete, you need to adjust it so that the spinning direction changes periodically, instead of just using it in the same direction for the entire polishing job. If you notice that even with the sand, you get to a point on the concrete where it isn't working as well, turn off the machine, reverse the spinning direction, and try it again. This should fix the problem.

Make sure you are using the grinding machine from side to side, and not in a circle. It is already spinning with the help of the diamond heads, so you don't need to also move it in a circular motion.