
Use a wet core bit with a hardened, steel-cutting crown, drill slowly with steady pressure, and let the bit cut the rebar rather than forcing it. Anchored, aligned drilling protects both the bit and the core rig.
| Mistake | Result |
|---|---|
| Heavy feed on rebar | Segment loss, bit jams |
| No water | Burnt crown, glazed steel |
| Unaligned drill | Wandering, oval hole |
| Ignoring steel sparks | Overheating, bit failure |
A:With a hardened crown, yes — slowly and steadily. Standard soft crowns will wear fast on steel.
A>Slower. Reduce feed so the crown grinds the steel instead of grabbing it.
A:Higher resistance, a change in sound, and steel chips in the slurry. Ease off and continue steadily.
Rebar is a test of feed control and water flow. A hardened wet bit like the Diamond Core Drill Bit (Wet) — JOY-DCB-W or the segmented Diamond Segment Core Drill — JOY-CDS handles reinforced concrete when driven steadily.