Quick Answer

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.

What Happens When You Hit Rebar

• The bit crown must cut the steel — a hardened crown survives this.
• Forcing the bit overheats segments and can break them.
• Without water, the steel edge quickly burns the crown.
• Misalignment causes the bit to wander and jam.

How to Drill Through Rebar Safely

1. Anchor the drill and confirm it is level and aligned.
2. Start with light pressure until the crown seats.
3. When you feel the rebar, reduce feed and let the bit cut.
4. Keep water flowing at full rate to cool the crown.
5. Clear the core regularly; steel chips can clog the tube.

Common Mistakes

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

Frequently Asked Questions

Q: Will a core bit cut rebar?

A:With a hardened crown, yes — slowly and steadily. Standard soft crowns will wear fast on steel.

Q>Should I drill faster or slower on rebar?

A>Slower. Reduce feed so the crown grinds the steel instead of grabbing it.

Q: How do I know I am hitting rebar?

A:Higher resistance, a change in sound, and steel chips in the slurry. Ease off and continue steadily.

Conclusion

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.

Planning Around Rebar

On jobs where rebar density is unknown, start a shallow trial hole before anchoring the rig for the full depth. Expect reduced progress once the crown engages steel, and slow the feed rather than increasing pressure — the bit cuts rebar by grinding it, not by forcing through it. Keep the water volume generous, clear slurry often, and let the crown cool between holes if the cut becomes excessively hot. If your regular bits lose segments quickly on a particular structure, ask the manufacturer for a hardened-crown option sized to your machine; matching the crown to the rebar frequency is cheaper than replacing bits every shift.