A #54 drill measures 0.0550 inch (1.397 mm). The closest fractional drill is 1/16" (0.0625") and the closest metric drill is 1.4 mm (0.0551").
What are the #54 drill equivalents?
| Drill | System | Decimal (in) | mm | Difference (in) |
|---|---|---|---|---|
| #54 | number | 0.0550 | 1.397 | 0 |
| 1.4 mm | metric | 0.0551 | 1.400 | +0.0001 |
Drill sets that include this size
Number and letter sizes come in indexed sets; buy the set rather than single drills.
What speed should a #54 drill run?
| Material | RPM (HSS) | Feed (in/rev) |
|---|---|---|
| 6061-T6 aluminum | 13,890 | 0.0011 |
| 360 free-machining brass | 10,417 | 0.0010 |
| 1018 cold rolled steel | 5,556 | 0.0008 |
| 304 stainless steel | 2,778 | 0.0006 |
Starting points from conservative HSS drilling speeds. Small drills often call for more RPM than a benchtop drill press offers; run at the top speed and feed gently. Use cutting oil in steel and stainless, and clamp the work: never hold it by hand.
Cutting fluid for drilling
Frequently asked questions
What is a #54 drill in inches?
0.0550 inch, which is 1.397 mm. Number drills get smaller as the number rises, so the next number up is a smaller drill. If you do not have this exact size, 1.4 mm is within 0.0001 inch.
What tap uses a #54 drill?
No common UNC or UNF thread uses it as its standard 75% tap drill, but it often serves as an alternative drill for a slightly different percentage of thread, or as a clearance or pilot size. The tap drill chart lists every standard pairing.