Quick Answer

Polycrystalline diamond (PCD) tools remove the coating; diamond grinding blocks profile the concrete underneath. For epoxy, adhesive, paint or self-levelling topping on Brazilian floors, run one PCD pass at 1–3 mm depth, then a metal bond block in 16# or 30/40 to clean the residue and open the surface. Skipping the second pass is why so many jobs come back with a patchy, uneven finish.

Why PCD Comes First

A diamond segment grinds concrete, but it slides over a tough polymer coating and loads up instead of cutting. PCD is a different material: a sintered diamond compact with a flat, hard face that shears coatings rather than grinding them. That is why a PCD block removes a 2 mm epoxy layer in a couple of passes, where a metal bond block would polish the epoxy and burnish it.

Once the coating is gone, the concrete surface is scarred and uneven — PCD leaves shallow gouges by design. The following metal bond pass levels the scars and gives the resin steps a clean base. If you want to compare both approaches in detail, see PCD vs diamond grinding for coating removal.

Coating Types on Brazilian Floors

Coating	Typical thickness	Best first tool
Epóxi autonivelante (self-levelling epoxy)	1.5–4 mm	PCD, 1/4 or 1/2 PCD
Epóxi de alta espessura / argamassa epóxi	3–6 mm	Full PCD plus alloy bar
Adesivo de carpete / cola de PVC	0.3–1.5 mm	PCD; small PCD where the layer is thin
Tinta epóxi ou poliuretano	0.1–0.5 mm	PCD with small PCD, or coarse diamond block
Contrapiso autonivelante (self-levelling screed)	2–10 mm	PCD + hard bond block
Resina / verniz de acabamento	0.1 mm or less	Coarse diamond block, PCD only if it smears

PCD Specification Table

All trapezoid PCD tools below take M6, 9 mm or Diamatic three-hole plates, so they fit the universal heads that dominate the Brazilian market.

Model	PCD configuration	Segment	Connection	Where it works best
JOY-TP-PCD1A1	1 full PCD + 1 alloy dot	—	M6 / 9 mm / Diamatic holes	Thick coatings, screed and epoxy toppings
JOY-TP-PCD2B1	2 × 1/4 PCD + 1 bar segment	1 bar	M6 / 9 mm / Diamatic holes	General epoxy and adhesive removal with residual grinding
JOY-TP-PCD3R1	3 × 1/2 PCD + 1 round segment	1 round	M6 / 9 mm / Diamatic holes	Hard, thick epoxy; less gouging on soft concrete
JOY-TP-PCD5	5 small PCD	—	M6 / 9 mm / Diamatic holes	Thin paint, varnish and glue layers
JOY-TPF-PCD2B1	2 × 1/4 PCD + 1 bar segment	1 bar	Fast Change System	Quick-change heads, high-volume coating removal
JOY-CW-PCD6	6 × 1/4 PCD	—	5/8"-11, M14, 22.23 mm, 16 mm	Hand grinder and edge work

Two families cover most jobs: 1/4 PCD with an alloy or diamond segment for everyday coating removal, and full or 1/2 PCD for thick epoxy and self-levelling toppings. On soft concrete, three smaller PCD cut less deeply than one full PCD, which keeps the gouges shallow.

Match PCD Size to Coating Thickness

• Under 1 mm — small PCD tooling removes paint, varnish and thin glue without cutting into the slab.
• 1–3 mm — 1/4 PCD with a segment is the workhorse: it removes the layer and starts on the concrete in the same pass.
• 3 mm and above — 1/2 or full PCD; expect one roughing pass and one clean-up pass.
• Screed or topping with mesh — full PCD, slow feed, and check for wire before you run the head over it.

Pass Sequence That Works

Run the PCD pass in straight lines at a steady feed, about 1–2 mm per pass on epoxy, and do not stop the head in one place: heat softens epoxy and the tool starts smearing instead of shearing. Then switch to a 16# or 30/40 metal bond block to remove residue and level the gouges, follow with 60/80, and only then move to transitional pads. On large industrial floors in São Paulo and Minas Gerais, this two-stage approach is what keeps the schedule predictable.

Dust, Heat and Safety

Epoxy and polyurethane dust is a health hazard, not ordinary concrete dust. Use a HEPA extraction unit rated for the grinder, keep the shroud sealed, and wear P2/P3 respiratory protection. Do not wet down epoxy dust to control it — it turns into a smear that clogs the shroud and hides the surface.

FAQ

Can I remove epoxy with a normal diamond block?

Only thin paint and varnish layers. On anything above roughly 0.5 mm, a metal bond block polishes the coating instead of removing it, and you spend more time and more blocks than a PCD pass would have cost.

How many PCD passes before switching to diamond?

Usually one, sometimes two on thick self-levelling toppings. Stop as soon as you see consistent concrete; a third pass only deepens the gouges.

Do PCD tools work on glue residue from carpet or PVC?

Yes. Adhesive layers are thin and gummy, so use small or 1/4 PCD at a slow feed, then clean the residue with a 16# block before it re-bonds to the surface.

Specify the PCD Set for Your Floor

Tell us the coating type, the measured thickness, the concrete condition underneath and the machine model. We will match the PCD configuration and the follow-up block so one order covers both stages. Browse grinding and coating removal tools, or read which PCD shape suits thick coatings.