Black cutback adhesive and VCT glue come off concrete fastest with PCD grinding discs on a floor grinder. Chemical removers soften the glue but leave a smeary residue; scraping is slow. PCD tooling shears the adhesive off in one pass and leaves a clean, profile-ready slab.
Black cutback adhesive is asphalt-based. It is soft, sticky, and loads up ordinary diamond discs instantly. A standard metal-bond pad will glaze and stop cutting within minutes. You need PCD—polycrystalline diamond—which does not load and shears through the rubbery glue.
See the full range in our concrete grinding discs category.
Adhesive removers (citrus or soy-based) help on small patches but require 30-60 minutes dwell time and leave the slab wet. They are a complement to grinding, not a replacement. Do not use them on large commercial slabs.
If the building was built before 1980, assume old VCT backing may contain asbestos. Do not dry grind without testing. Hire an abatement professional if asbestos is confirmed.
A: It will load up almost immediately. PCD is required for any asphalt-based adhesive.
Run a hand across the floor. It should feel like clean concrete, not tacky. A black rag wiped over the slab should not pick up black residue.
PCD leaves scratch marks but does not gouge concrete. The follow-up metal-bond pass brings the slab back to a uniform profile.
Vinyl glue is a PCD job. Scrape, PCD grind, metal-bond finish, vacuum. contact JOY TECH for PCD discs that fit your grinder.
