Excessive Tapping Torque
- Use larger drill size.
- Try to shorten thread length.
- Increase cutting angle.
- Use a tap with more thread relief and reduced land width.
- Use spiral pointed or spiral fluted taps.
Incorrect Tap Selection
- Avoid chip packing in the flutes or the bottom of the hole. Use spiral pointed or spiral fluted taps or fluteless taps.
- Apply correct surface treatment such as steam oxide or TiN.
Operating Conditions
- Reduce tapping speed.
- Avoid misalignment between tap and the hole and tapered hole.
- Use floating type of tapping holder.
- Use tapping holder with torque adjustment.
- Avoid hitting bottom of the hole with tap.
Tool Conditions
- Do not grind the bottom of the flute.
- Avoid too narrow a land width.
- Remove all worn sections when regrinding the flutes.
- Regrind tool more frequently.
