Concrete Grinding
in Gilbert.

Concrete Grinding is the pre-polish or pre-coating work that determines whether the final surface lasts. Mechanical surface prep using planetary diamond grinders. Removes laitance, opens the slab, and creates the surface profile required for whatever polish, coating, or repair work comes next.

Most polished concrete failures are prep failures. Skipped grinding, missed joint repair, untreated cracks, insufficient densification, every one of these shows up six months later as a worn surface, a delamination, or a polish that didn’t hold. Mint runs concrete grinding as a standalone service for GCs and facility managers who want the prep done right before another contractor handles the finish, or as part of a full polished concrete or coating install.

Where concrete grinding fits

• Pre-polish prep
• Pre-coating prep
• Surface leveling
• Profile correction
• Spall removal

What we bring to a concrete grinding job

Planetary diamond grinders, walk-behind and ride-on platforms for large slabs, HEPA-filtered dust collection for occupied buildings, PCD attachments for coating removal, semi-rigid polyurea for joint fill, polishable epoxy patch compounds, lithium-silicate densifier, the full slab-prep toolkit. Danny is on every job. No subcontractors.

If you need concrete grinding done as a one-off before another contractor handles the finish, that’s standard scope. Request a walkthrough with the slab address.

Matching the bond to the slab, not the other way around

The part nobody outside the trade expects is that the metal holding the diamonds matters more than the diamonds. A soft-bond tooling wears away quickly, constantly exposing fresh diamond, and that is what you want on a hard slab that would otherwise glaze your segments. A hard bond holds its diamonds longer and belongs on a soft, green, or sandy slab that would chew through soft tooling in an afternoon. Run the wrong one and the symptoms are obvious once you know them: tooling that stops cutting and starts skating, or tooling that disappears at four times the expected rate and leaves gouges behind.

Valley slabs are not consistent about this. A 1990s tract-built garage in Gilbert with a hard steel-trowel finish behaves nothing like a 2019 tilt-up in an industrial park, and older commercial pours often vary in hardness from one bay to the next depending on who finished which section that day. Danny runs a scratch test on the walkthrough and starts with test passes in a corner before committing tooling to a whole floor. That is ten minutes that saves a day.

The sequence and what each pass is for

Grinding is not one operation repeated. Each step has a job, and the only rule that never bends is that every pass has to fully remove the scratch pattern left by the pass before it.

• 30 grit metal bond. The aggressive opening cut. Takes off laitance, old coatings, glue, and high spots, and sets how deep into the slab you are going
• 60 to 80 grit metal. Refines the cut and erases the coarse scratch pattern. Skip this and the 30-grit lines telegraph through every finish above them
• Densifier goes in here, while the pores are open
• 100 to 200 grit. The handoff from cutting to refining, and the point where the surface starts reading flat rather than scarred

Where it stops depends on what happens next. A floor getting a coating stops in the metal-bond range because the coating needs texture to key into. A floor getting polished carries on through resin steps to whatever gloss the spec calls for. Grinding for coating and grinding for polish are genuinely different jobs, and the wrong endpoint is expensive to undo.

Surface profile, in plain terms

Coating manufacturers write their warranties around a required profile, expressed on the ICRI concrete surface profile scale. Low numbers are nearly smooth, high numbers are rough as coarse sandpaper. A thin sealer wants something close to CSP 1 or 2, a standard epoxy build wants CSP 2 to 3, and a heavy mortar or urethane cement system can want CSP 4 or higher. If a coating fails and the manufacturer asks how the slab was prepped, an acid etch or a buffed floor is where that conversation ends badly. Mechanical profiling is the only method most spec sheets accept, and we document what we cut so the paperwork holds up.

Dust, and why it is not optional here

Dry grinding concrete throws respirable crystalline silica, which OSHA regulates specifically under Table 1 of the silica standard. The compliant path we run is a shrouded grinder tied to a HEPA-filtered dust extractor sized to the tool, with a pre-separator so the filters stay usable. Done properly a crew can grind inside an occupied office suite with the neighbors none the wiser, and the floor stays cleaner for it, because dust left on the slab gets driven back into the surface by the next pass.

Desert dust adds a second problem the rest of the country does not deal with. Fine wind-blown grit blows in through an open overhead door and lands on a floor between passes, and any of it left under a densifier application or a sealer shows up permanently. Doors stay closed, the zone stays sealed, and the slab gets vacuumed between every step rather than at the end. If you want to know what your floor is going to do under a diamond, the fastest answer is a test patch in a corner, and Danny will cut one on the walkthrough.