How to Use a Concrete Grinder to Cut Concrete

Mason blocks.

Concrete is generally cut by masons and tradesmen who have learned the proper technique and use an aptly-equipped angle grinder. With the right cutting blade and a few masonry tools, cutting concrete can be as simple as sawing wood, and just as safe.

Things You'll Need

• Pencil
• T-square
• Eye protection
• Gloves
• Cold chisel
• Hammer
• Angle grinder
• 4-inch diamond blade

Instructions

1. Mark the cut with a pencil and T-square. Put on protective goggles and gloves.

2. With a cold chisel in one hand and a hammer in the other, place the edge of the chisel at one end of the cut mark.

3. Hammer the chisel into the concrete until you form a shallow groove. This should only take two or three substantial blows.

4. Place the chisel at the other end of the cut mark and hammer in another shallow groove with the chisel. You are creating a guide channel for the angle grinder's blade.

5. Chisel another groove in the midpoint of your block or slab. Depending on the length of your cut, you may need two middle groove channels. If your cut is less than 18 inches, three guide grooves are sufficient.

6. Holding the grinder with both hands, place the spinning blade in one of the guide grooves and follow the pencil mark through the corresponding guide grooves. Continue cutting along the groove until your block or slab is cut to your specifications. Depending on the depth of your block or slab, this may take a few passes with the grinder.

Tips & Warnings

• Always wear eye protection when using a chisel or angle grinder. Keep both hands on the angle grinder when in use.

Resources

• Concrete Cutting: The Unknown Niche