M2 × 0.4 Tap Drill Size & Thread Specs
Everything for a M2 × 0.4 coarse pitch thread on one page: tap drill (1.6 mm), clearance holes, wrench and hex key sizes, and the nearest inch thread.
SP-TD-01 · M2 × 0.4
M2 × 0.4 specs
SizePlate
M2 × 0.4 · tap with
1.6 mm drill
.0630″
1.6 mm · 77% thread
- Inch drill
- 1/16 · .0625
- Clearance
- 2.2 / 2.4 mm
Thread
- Nominal size
- M2 · .0787″
- Pitch
- 0.4 mm · 63.5 TPI
- Series
- coarse
Drilling
- Tap drill
- 1.6 mm · .0630
- Inch substitute
- 1/16 · .0625
- Close fit
- 2.2 mm
- Normal fit
- 2.4 mm
- Free fit
- 2.6 mm
Nearest inch
- Thread
- #1-64
- Major diameter
- .0730″
- Threads per inch
- 64
- Tap drill
- #53
- Interchangeable
- No
Not interchangeable means the threads look close but won't run together: forcing one into the other strips both.
Drill size by thread percentage
Larger drill, less thread, easier tapping. 75% is the usual target.
| Drill | Decimal | mm | Thread |
|---|---|---|---|
| 1/16 | .0625 | 1.59 | 79% |
| 1.6 mm | .0630 | 1.6 | 77% |
| #52 | .0635 | 1.61 | 74% |
| 1.7 mm | .0669 | 1.7 | 58% |
| #51 | .0670 | 1.7 | 57% |
Neighboring sizes
- M1.6 × 0.35tap 1.25 mm
- M2.5 × 0.45tap 2.05 mm
- M3 × 0.5tap 2.5 mm
- M3 × 0.35tap 2.65 mm
- M4 × 0.7tap 3.3 mm
- M4 × 0.5tap 3.5 mm
Questions
What does M2 × 0.4 mean?
An ISO metric thread with a 2 mm major diameter and a 0.4 mm pitch (the distance from one thread crest to the next). It’s the coarse pitch for M2.
Can I use a 1/16 drill instead?
Usually. 1/16 is .0625″ against .0630″ for the 1.6 mm drill, which changes the thread engagement by a few percent at most.