M5×0.8 tap drill size
Use a 4.2mm drill (4.20 mm) for a M5×0.8 cutting tap at 75% thread.
| Tap type | Drill | Decimal (mm) |
|---|---|---|
| Cutting tap, 75% thread | 4.2mm | 4.20 |
| Cutting tap, 50% thread (hard material) | 4.4mm | 4.40 |
| Roll / form tap, 65% thread | 4.65 mm | 4.65 |
| Helicoil / STI insert (M5×0.8×1D) | 5.6mm | 5.60 |
- Pitch
- 0.8 mm
- Major Ø
- 5.00
- Pitch Ø
- 4.48
- Minor Ø
- 4.13
Common questions
- What size drill for a M5×0.8 tap?
- Use a 4.2mm drill (4.20 mm) for a M5×0.8 cutting tap at 75% thread.
- What drill for a M5×0.8 roll (form) tap?
- About 4.65 mm; the nearest standard drill is 4.65 mm. Check your tap maker's table.
- What drill for a M5×0.8 Helicoil?
- Drill 5.6mm (5.60 mm), then tap with the M5×0.8 STI tap.
Other Metric sizes
Drill sizes from Machinery's Handbook and ASME B1.1/B1.13M; roll tap sizes from the form-tap formula. Tap and insert makers' tables are authoritative.