How to grind a garage floor the easy way all garage floors current electricity definition physics


These are the basic tools that you will need to acquire before you start grinding your garage floor. If you already have some of these or know of someone who can lend them to you, then obviously it will cost you even less. The dust shroud for the angle grinder is optional and will need to be attached to a shop vacuum in order to use it. Keep in mind that pricing may vary depending on your area.

Most of the floor maintainers that Home Depot rent do not have an optional dust shroud attachment. This will require that you grind the floor wet if you want to avoid the dust. If you find a rental with the dust shroud attachment, you will need to rent a shop vacuum to go with it or use your own.

The small angle grinder and cup wheel works well for feathering any garage floor patchwork or crack repair as well as grinding the areas and edges near the wall that the Diamabrush cannot reach. It’s also good for smoothing out the raised edges of large contraction joints if opting for the seamless garage floor look or grinding down any unusual high spots.

If you will be grinding dry with your own shop vacuum, then one other tool you may want to purchase is a Dust Deputy. Concrete dust is very fine and will clog up the filtration system of a standard shop vacuum fairly quickly requiring frequent stops to clean them out. The Dust Deputy works by creating its own dust collection system that keeps the filters of the vacuum virtually dust free.

Next, if you have elected not to use a dust shroud and vacuum, be prepared for the dust that will follow. While the Diamabrush does not create as much dust as a typical 7″ concrete grinder with a turbo cup wheel, you will still have a small cloud of dust that will coat everything in your garage.

When grinding wet, start by wetting the surface of the concrete that you are going to grind. It’s best to work in sections when you do this. Using the floor buffer with the Diamabrush attachment, start by grinding the surface of the concrete, slowly working the machine in a circular motion. It will only take a few minutes to figure out how long to work an area before you need to move on.

To check your work, use the hose to spray the area clean with a high pressure nozzle and then run your fingers across the surface. It should feel like medium grit sandpaper and have a more granular look. Continue this way, grinding the garage floor one section at a time until you are done. Make sure to work the machine all the way up against the stem walls of the garage floor, getting as close as you can.

Note: When grinding with the wet method, do not let the wet slurry dry out. It’s a bear to clean out of the concrete properly if you do and can lead to a coating failure if it isn’t completely removed. Each time you finish a section, use your hose to blast the area clean while it’s still wet and then move on to your next section.

Because wet grinding can create quite the slurry, we recommend that before you blast a section clean, use a wet vac to suck up the majority of the slurry. This helps tremendously with keeping the amount of slurry that you hose out of your driveway down to a minimum.

Once done, this will leave a strip about 2″-3″ wide around the perimeter of the walls that the Diamabrush could not reach. There will be more in the corners. Use the small 4 ½” grinder with the diamond cup wheel to remove this remaining strip of concrete and the larger areas in the corners.

Be careful to keep the cup wheel flat on the garage floor when grinding. If you apply too much pressure or angle it too much on the surface, it will leave “kiss marks”. These are small half-moon divots that can potentially show through your coating.

The concrete needs to be fairly dry for the area that you are grinding when using the cup wheel. If it’s wet, you will need to use a ground fault circuit interrupter to prevent electrocuting yourself with the angle grinder. You can purchase these for about $25. Many times you can use the power cord extension that comes with the floor maintainers if you still have time on the rental. They usually have a GFCI built into the cord.

Another option for grinding your garage floor that is being used quite successfully is the 7” Diamabrush hand tool. This one is made to fit a 7” angle grinder and works fairly quickly as well. You will need a dust shroud when using this tool and it works best with a variable speed grinder.

Diamabrush says that the slower the RPM’s the better. The faster speed grinders have a tendency of heating up and clogging the blades. If your only option is a single speed grinder, don’t use one that spins any faster than 6000 rpm’s. If you are worried about the speed, Diamabrush says grinding wet will keep the blades cool and prevent clogging or glazing.

Another tip is to keep it flat and do not lean into it in an effort to make it work harder. The weight of the grinder is enough to do the work. Depending on how much suction your shop vacuum creates, you may need to shim the tool with a washer to raise the shroud off the floor to avoid suction lock. Some shrouds have a vent to adjust for this as well. Either way, these tools make quick work of the concrete. Shop Vac Recommendation

If you are thinking of purchasing a new shop vac, we highly recommend that you look at this Dustless Wet/Dry shop vacuum by Dustless Technologies. These are excellent vacuums that work extremely well when vacuuming up concrete dust, drywall dust, and variety of other fine dust particulates.

Professional installers are using these more and more as a backup or even as a replacement to the much higher priced specialized concrete dust vacuums. You can read the great reviews on these and find the best prices with free shipping here from Amazon .

To check, run your finger across the surface when it has dried. If your finger is clean and doesn’t have white residue on it then you are good to go. Another test is press a strip of duct tape to the concrete and then pull it up. It should stick fairly well and come up clean.

If you have a lot of white residue, then this is excess dust that did not get blasted out and will need to be cleaned. The best way is to mix up a solution of TSP (Trisodium phosphate) in a bucket, spread it out on the floor and lightly scrub it with a push broom or long handled scrub brush.

Using your high pressure nozzle, rinse the concrete real well making sure there is no more solution left behind. Work in sections if you need to so that the solution will not dry before you rinse it out. This will help lift any remaining slurry and dust that is in the pores of the concrete when you rinse.

If you did a dry grind, the easiest way to insure the concrete is clean and ready is to use the wide mouth attachment on your shop vacuum and just vacuum all the dust up. What’s nice about this method is the fact you can start right away with applying your floor coating since there is no water on the floor that needs to fully dry.

Once the floor is done, test different areas by sprinkling a little water on the surface paying particular attention to any areas that were coated in oil or grease or where you may have used a tire dressing that dripped onto your concrete. It should absorb the water fairly quickly. If it just sits on the surface, then you may need to regrind and/or re-clean that spot before you epoxy.

Grinding a garage floor has just become much easier with this tool from Diamabrush. It can be done in less than a day and it’s much safer to use than an acid etch. Best of all, it provides the best surface profile for your epoxy floor coating to adhere to.