Concrete grinding and polishing contractors reach for the EDCO QC1B-HC-0030 when a slab is too dense and unyielding for a standard bond to bite into. This 30-grit Single Dyma-Dot is EDCO's Hard Concrete formulation, built to keep cutting on tight, low-porosity floors where a softer-bond diamond dot would glaze over instead of grinding down. It mounts to EDCO's Magna-Trap Quick-Change system with a magnetic backing, so crews can swap tooling mid-job without wrenches or downtime.
Built For
- Aggressive coarse-grit grinding on dense, hard concrete slabs
- Removing thick epoxies, urethanes, and weatherproofing membranes
- Stripping mastics, thin-sets, and old coatings ahead of a polish or overlay
- Flattening high spots and leveling uneven concrete without gouging
- First-pass coating removal before stepping down to finer-grit dots
Specifications
- Grit: 30 (coarse) for initial, aggressive material removal
- Formulation: Hard Concrete bond, engineered for dense, low-aggregate slabs where a softer bond would glaze over instead of cutting
- Style: Single Dyma-Dot, EDCO's aggressive dot pattern suited to heavy coating removal and hard-surface grinding
- Backing: Magnetic Quick-Change, mounts and releases without bolts or tools
- Disc compatibility: EDCO 7-inch and 10-inch Quick-Change Multi-Accessory Discs on Magna-Trap floor and turbo grinders
Frequently Asked Questions
How do I know if I need the Hard Concrete, Medium Concrete, or Soft Concrete version?
Match the dot's bond to your slab, not the other way around. Hard, dense concrete needs a Hard Concrete-formulated dot like this one so the tool keeps exposing sharp diamond as it works; a bond made for softer, more abrasive concrete tends to wear too fast or glaze over on a hard slab. If you're not sure how your floor will grind, EDCO's Medium Concrete dot is the general-purpose starting point, and you step to Hard Concrete if the medium dot glazes over and stops cutting.
How long will a 30-grit Dyma-Dot last?
Life depends on slab hardness, coating thickness, and grinder pressure, so it varies job to job. A clean, hard slab wears a dot far more slowly than a floor loaded with thick coatings or abrasive aggregate. Check the diamond segments between passes; once the dot stops removing material at a normal rate or the diamond surface looks smooth and glazed, it's time to rotate in a fresh dot.
How do I swap Dyma-Dots on the grinder?
The Quick-Change backing is magnetic, so dots slide on and off the Multi-Accessory Disc by hand, no bolts, adapters, or tools required. Line the dot up on the disc, press it into place, and it's ready to grind. Swap it out the same way when you change grit or move to a different job.
Which EDCO grinders and discs does this dot fit?
The QC1B-HC-0030 is built for EDCO's 7-inch and 10-inch Quick-Change Multi-Accessory Discs, used on Magna-Trap single- and dual-disc floor grinders and Magna-Trap turbo grinders. Confirm your machine is set up with the Multi-Accessory Disc before ordering replacement dots.
Should I start with 30 grit or move to a finer grit?
Start coarse. 30 grit is an aggressive, early-stage grit for removing coatings, leveling high spots, and opening up a hard slab; it's not a polishing grit. Once the surface is flat and the coating is gone, step up through EDCO's finer-grit Dyma-Dots to refine the finish.
Discount Cleaning Products is an authorized EDCO dealer, stocking genuine Magna-Trap Dyma-Dots and other EDCO surface-prep tooling for concrete grinding and polishing contractors. Our US-based team can help you match dot grit and bond to your slab and grinder setup.