You Can Wet-cut While Grinding and Honing Concrete

Grinding and Honing Concrete slab at the Concrete Decor Show in Florida
You’ll be surprised at the many benefits you’ll reap when using water to grind and hone concrete you’re going to polish. Photo from Concrete Decor archives

I venture to guess that most of the floor-covering installers reading this tip don’t consider “grinding or honing wet” an option when bidding polished concrete. I don’t blame you. In the floor covering industry, the idea of adding water to the concrete sounds crazy. Most of the time, you already have a significant concern with the relative humidity.

10 benefits of grinding and honing wet

Today, please consider the benefits of using water to grind and hone concrete that you have a contract to polish. I think its many benefits will surprise you:

  1. Water keeps diamond tooling cooler, preventing glazing.
  2. Slurry acts as a cutting solution or aid, similar to rubbing compound for your vehicle. Note: If the floor gets cleaned before each grit, slurry particles are the same size as the grit you’re using. This is how it aids in the production.
  3. Besides increasing tooling life, slurry helps keep the diamond points cleaner and sharper longer.
  4. Slurry decreases the chance of random scratches by cutting gentler.
  5. Due to the lubrication from the water/slurry, slurry decreases the fracturing of the surface.
  6. Slurry decreases the metal bond choice from seven hardness levels (colors) down to two.

Note: Easier for your crew to make the right choice and less inventory too!

  1. Less use of the vacuum, fewer cords to drag and less power to supply.
  2. A complete scratch pattern due to more available sharp-cutting surfaces.
  3. Decreases person-hours during the first steps of grinding and honing.
  4. Increases the pace that the machine operator can travel.
The process doesn’t need to be as messy as you think!

Use 36-inch or 48-inch rolls of paper and tape the top. I’ve found paper easier to keep in place than plastic. The paper gets exposed to only water and slurry, so staining isn’t a concern.

Have a slurry vac with a floor-mounted squeegee, an auto-scrubber equipped with brushes and a few foam squeegees. Then choose a slurry consolidator product (such as Slurry Slayer, Slurry Solutions, SlurryMonster or GelMaxx, among others).

Now decide if you’ll mix in a container or use bags to dispose the slurry once it’s no longer liquid. Will the crew dump the solidified material directly into a dumpster or tote it to the truck? If toting, what size bags can your crew carry? These are the major decisions.

Oh and, of course, talk to your distributor and buy a few sets of wet metal and transitional tooling. If you have electric machines, inspect all cords and plugs. Water and electricity don’t play nice, especially at three-phase, 480-volt power.

Let’s do it

Spray water so that a thin uniform puddle forms under and in front of the grinder. Keep it wet enough so the slurry is thinner than peanut butter and closer to the consistency of a milkshake. The slurry keeps the tooling cool for cutting/scratching and makes it much easier to squeegee.

Keep pushing slurry from the last pass to the pass area getting cut, reusing the water as long as possible. I suggest you use your hand-grinding guy to clean as you go. This way, he gets a chance to get up off his knees.

Check your tooling at least once an hour to make sure that the channels between segments stay clear. If not, clean them and begin again.

Some contractors prefer to solidify the slurry on the floor. They sprinkle and mix and then shovel the dry material into a bag or container. Once your crew tries it, they’ll quickly figure out what method they prefer.

Each time they complete a grit or direction (N/S, E/W), auto-scrub the entire area with a cleaner in the tank. Then inspect. As always, the time to fix something is now, before going to your next grit.

Here’s the tip

No rule says you must do X-number of wet-grinding passes before deciding to run dry. At a minimum at least, I advise you to run your metals wet. Changing from wet to dry is no big deal. The consensus says to stay wet until completing the grouting, densifying and coloring.

Or, instead, clean extremely well. Using fans, let the slab dry until the next shift and then apply product. For specific details, contact me. I can customize a system with your company, equipment and job site in mind.

Got more questions about your project?

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