Tapping troubleshooting

• Wrong tolerance
• Wrong tap for application
• Incorrect axial feed
• Tap speed too slow
• Wrong tool holder “over feed thread”​

• Choose tap with lower tolerance
• Refer to application charts
• Ensure feed rate is controlled

• Wrong tolerance
• Tap worn out
• Excessive pull off pressure
• Tap drill hole too small
• Material closing in after tapping

• Choose tap with higher tolerance
• Replace
• Adjust tapping attachment
• Increase drill diameter

Chipping

Cause

Solution

• Wrong tap for the material/application
• Incorrect or lack of lubricant
• Tap hitting bottom of hole
• Trapped chip
• Surface hardening in drilled hole

• Check tool selection
• Use appropriate emulsion or oil
• Increase drill depth or reduce thread depth
• Check tool selection
• Check drilling recommendations

Breakage

Cause

Solution

• Too high torque
• Tap worn out
• Incorrect or lack of lubricant
• Tap hitting bottom of hole
• Tap speed too high
• Trapped chip
• Tap drill hole too small

• Use tap holder with torque settings
• Replace
• Use appropriate emulsion or oil
• Increase drill depth or reduce thread depth
• Lower cutting speed, see recommendations
• Check tool selection

Rapid wear

Cause

Solution

• Wrong type of tap for the application
• Wrong surface treatment
• Incorrect or lack of lubricant
• Tap speed too high
• Surface hardening in drilled hole
• Tap drill hole too small

• Use a more wear resistant surface treatment
• Use appropriate emulsion or oil
• Lower the cutting speed, see recommendations
• Check drilling recommendations

Built-up edge (BUE)

Cause

Solution

• Wrong type of tap for the application
• Tap worn out
• Incorrect or lack of lubricant

• Replace
• Use appropriate emulsion or