If the core bit stops drilling, check in order: glazed crown, wrong bit type for the material, low RPM, poor anchoring, and worn segments. Most problems are fixed by dressing the crown, adding water, or correcting speed and feed.
| Symptom | Cause | Fix |
|---|---|---|
| Slides, no progress | Glazed crown | Dress on an abrasive block |
| Slow, hot | Low RPM or no water | Check speed, add water |
| Wanders at start | Poor anchoring | Anchor the rig firmly |
| Stops on steel | Soft crown on rebar | Hardened crown, slower feed |
| No diamond left | Worn segments | Replace the bit |
A>Whenever the crown looks shiny and the cut slows. Regular light dressing keeps the crown sharp.
A>Overheating from no water, too fast feed, or wrong bit type. Stop, cool, correct the cause.
A>Usually not economically. Replace it when the segment height is nearly gone.
Diagnose in order: glaze, water, speed, anchor, wear. A matched bit like the Diamond Core Drill Bit (Wet) — JOY-DCB-W or Diamond Dry Core Bit — JOY-DDC avoids most of these problems when run correctly.
