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U drill bit size
U drill = .3680 in = 9.35 mm. Closest metric drill: 9.3 mm.
Taps that use a U drill
- 7/16-14 UNC: about 75% thread
Nearby drill sizes
| Drill | Type | Inch | mm | Difference |
|---|---|---|---|---|
| 11/32 | fraction | .3438 in | 8.731 | -24.2 thou |
| S | letter | .3480 in | 8.839 | -20.0 thou |
| T | letter | .3580 in | 9.093 | -10.0 thou |
| 23/64 | fraction | .3594 in | 9.128 | -8.6 thou |
| U | letter | .3680 in | 9.347 | 0.0 thou |
| 3/8 | fraction | .3750 in | 9.525 | 7.0 thou |
| V | letter | .3770 in | 9.576 | 9.0 thou |
| W | letter | .3860 in | 9.804 | 18.0 thou |
| 25/64 | fraction | .3906 in | 9.922 | 22.6 thou |
1 thou = 0.001 in = 0.0254 mm. Drills a few thou apart are usually interchangeable for clearance holes, but not for tap drills or reamer pilots.