Printed from Kezuriba (kezuriba.net/en/troubles/drill-chip-jam/)

Chips clog (drilling)

Drilling Drilling

Check first

Cutting conditions (speed, feed) are unsuitable, so chips are long
Insufficient coolant or external supply
Edge geometry unsuited to the workpiece material

Try first

Use step feed, or break chips with a dwell
Increase the feed to break chips
Use through-coolant and increase the pressure (guideline for indexable: 1.5 MPa or more)

?Likely causes

Cutting conditions (speed, feed) are unsuitable, so chips are longAgreed by 2+ makers^[1][2][3][4]
Insufficient coolant or external supplyAgreed by 2+ makers^[1][3][2]
Edge geometry unsuited to the workpiece materialOne maker^[1]

✓Fixes

Cutting conditions

Use step feed, or break chips with a dwellAgreed by 2+ makers^[4][3][5][6]
Increase the feed to break chipsAgreed by 2+ makers^[4][6][7][5]

Tool

Use a drill with a small web thickness (large chip pockets)One maker^[2]

Coolant

Use through-coolant and increase the pressure (guideline for indexable: 1.5 MPa or more)Agreed by 2+ makers^[3][1][2][4]

↔Related problems

Hole becomes oversized (drilling)Hole becomes undersized (drilling)Hole bends or leans (poor straightness)Hole position shifts or hole is not round (rice-ball shape)Drill breaks Burrs at the hole exit (breakthrough)Drill chipping (periphery, chisel edge)Drill wears quickly (peripheral corner, margin, center)

📚Sources

Causes and fixes are summarized in our own words from cutting-tool makers’ troubleshooting guides and technical data. “Agreed by 2+ makers” means two or more makers say the same thing.

Sandvik Coromant — Drilling wear and troubleshooting sandvik.coromant.com
Mitsubishi Materials — Hole making troubleshooting mmc-carbide.com
Tungaloy tungaloy.com
Mitsubishi Materials — Advanced Drilling: Trouble shooting mmc-carbide.com
Tungaloy tungaloy.com
OSG — Series No.8 End mills, Table 7.1 Troubleshooting, pp. 61-62 osg.co.jp
OSG — Countermeasures for oversized holes faq.osg.co.jp