Printed from Kezuriba (kezuriba.net/en/troubles/material-copper/)

Copper and copper alloy quirks

Material-specific problems TurningMillingDrillingTappingReaming

Check first

Soft and ductile, so welding tends to degrade the finished surface
Soft and heavy, so beware of deflection when machining on a cantilever
Internal threads tend to shrink from elastic recovery

Try first

Choose sharp tools (for copper, aluminum, or stainless steel, or coated products)
For taps, consider oversize

?Likely causes

Soft and ductile, so welding tends to degrade the finished surfaceOne maker^[1]
Soft and heavy, so beware of deflection when machining on a cantileverOne maker^[1]
Internal threads tend to shrink from elastic recoveryOne maker^[2][3]

✓Fixes

Tool

Choose sharp tools (for copper, aluminum, or stainless steel, or coated products)One maker^[4]
For taps, consider oversizeOne maker^[2][3]

↔Related problems

Stainless steel quirks (work hardening, welding, boundary wear)Aluminum alloy quirks (welding, built-up edge, chips)Titanium and titanium alloy quirks (heat, welding, ignition)Cast iron quirks (powdery chips, edge chipping, black scale)Hardened steel (high-hardness steel) quirks Heat-resistant alloy (Ni-base alloy, etc.) quirks Magnesium alloy quirks (chip ignition)Mild steel (low-carbon steel) quirks

📚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.

Mitsubishi Materials — Workpiece material applications: N series mmc-carbide.com
OSG — Tool Communication Series No.6 Taps, "12. Troubleshooting in tapping operations," pp. 59-62 osg.co.jp
OSG — Series No.34 High-speed synchro taps, "8. Troubles and countermeasures," pp. 28-29 osg.co.jp
OSG — Machining C1100 (tough pitch copper) faq.osg.co.jp