What is a 19.25 mm drill in decimal and mm?

0.7579 in, or 19.250 mm; nearest fractional drill: 49/64" (0.7656 in, +0.0077 in); nearest number / letter drill: Letter Z (0.4130 in, -0.3449 in).

What RPM for a 19.25 mm drill in steel?

In low-carbon steel (1018) an HSS 19.25 mm drill (0.7579 in) runs about 450 RPM at 90 SFM; a carbide drill about 1,510 RPM at 300 SFM. RPM = 3.82 × SFM ÷ D.

What feed for a 19.25 mm drill?

About 0.0115 in/rev in mild steel, 0.0111 in/rev in aluminum and 0.0095 in/rev in 304 stainless. At 450 RPM that is 5.18 IPM in steel (IPM = RPM × IPR).

What RPM for a 19.25 mm drill in aluminum?

1,260 RPM with HSS (250 SFM) or up to 3,020 RPM with carbide (600 SFM), feeding about 0.0111 in/rev.

What tap uses a 19.25 mm drill?

M20x1.5 (form (roll) tap, 65% thread).

19.25 mm drill size

A 19.25 mm metric drill is 0.7579 in (19.250 mm). It is the form (roll) tap, 65% thread drill for M20x1.5.

Decimal inch: 0.7579
Millimeters: 19.250
Nearest 1/64: 49/64" (-0.0078)
Type: metric drill

Nearest equivalents in other systems

Drills closest to 19.25 mm
System	Drill	Inch	mm	Difference
Fractional	49/64"	0.7656	19.447	+0.0077 in
Number / letter	Letter Z	0.4130	10.490	-0.3449 in

Speeds and feeds: in mild steel an HSS drill starts at about 450 RPM and 0.0115 in/rev (5.18 IPM); in 6061 aluminum about 1,260 RPM.

19.25 mm drill speeds and feeds by material

Jobber-length twist drill, D = 0.7579 in. RPM = 3.82 × SFM ÷ D, rounded to 10. Feed per rev scales with diameter and material; IPM = RPM × IPR.

19.25 mm drilling speeds
Material	HSS SFM	HSS RPM	Carbide SFM	Carbide RPM	Feed (in/rev)	HSS IPM	Carbide IPM
Aluminum (6061)	250	1,260	600	3,020	0.0111	14.0	33.5
Brass / free-machining	150	760	400	2,020	0.0090	6.84	18.2
Low-carbon steel (1018)	90	450	300	1,510	0.0115	5.18	17.4
Alloy steel (4140, annealed)	70	350	250	1,260	0.0120	4.20	15.1
Stainless 304	40	200	150	760	0.0095	1.90	7.22
Gray cast iron	80	400	250	1,260	0.0100	4.00	12.6
Titanium 6Al-4V	25	130	100	500	0.0055	0.72	2.75
Plastics (acetal)	300	1,510	500	2,520	0.0070	10.6	17.6

Metric: Vc (m/min) = SFM × 0.3048; feed (mm/rev) = in/rev × 25.4. In steel, 450 RPM × 0.292 mm/rev = 131 mm/min.

Worked example: 19.25 mm drill in 1018 steel

HSS drill in low-carbon steel: 90 SFM.
RPM = 3.82 × 90 ÷ 0.7579 ≈ 450 RPM.
Feed for a 0.758 in drill in mild steel ≈ 0.0115 in/rev.
IPM = 450 × 0.0115 = 5.18 IPM.

Peck cycle by hole depth

19.25 mm drill: depth and canned cycle
Depth	Cycle	Peck	Note
3×D = 2.274 in (57.8 mm)	G81 (no peck)	None	Up to 3×D a sharp drill clears chips on its own.
5×D = 3.789 in (96.3 mm)	G73 chip-break	1 × D	Chip-break pecks; full retract if chips pack (soft aluminum, stainless).
8×D = 6.063 in (154 mm)	G83 full retract	0.5-1 × D, shrinking with depth	Retract to clear chips; reduce feed ~10-20% past 5×D.

Taps that use a 19.25 mm drill

M20x1.5 — form (roll) tap, 65% thread

Nearest drills

49/64": 0.7656 in / 19.447 mm (+0.0077 in)
3/4": 0.7500 in / 19.050 mm (-0.0079 in)
19.0 mm: 0.7480 in / 19.000 mm (-0.0098 in)
19.5 mm: 0.7677 in / 19.500 mm (+0.0098 in)

Drill speed calculator, prefilled for 19.25 mm Drill finder: sizes near 19.25 mm Metric drill chart Decimal equivalent chart

Common questions

What is a 19.25 mm drill in decimal and mm?: 0.7579 in, or 19.250 mm; nearest fractional drill: 49/64" (0.7656 in, +0.0077 in); nearest number / letter drill: Letter Z (0.4130 in, -0.3449 in).
What RPM for a 19.25 mm drill in steel?: In low-carbon steel (1018) an HSS 19.25 mm drill (0.7579 in) runs about 450 RPM at 90 SFM; a carbide drill about 1,510 RPM at 300 SFM. RPM = 3.82 × SFM ÷ D.
What feed for a 19.25 mm drill?: About 0.0115 in/rev in mild steel, 0.0111 in/rev in aluminum and 0.0095 in/rev in 304 stainless. At 450 RPM that is 5.18 IPM in steel (IPM = RPM × IPR).
What RPM for a 19.25 mm drill in aluminum?: 1,260 RPM with HSS (250 SFM) or up to 3,020 RPM with carbide (600 SFM), feeding about 0.0111 in/rev.
What tap uses a 19.25 mm drill?: M20x1.5 (form (roll) tap, 65% thread).

Nearby drill sizes

Sources

Machinery's Handbook, 31st ed., Speeds and Feeds for Drilling, Reaming and Threading (Tables 17-23) — HSS and carbide drilling SFM (rounded).
RedLine Tools (Productivity Inc.) catalog p. 340, Cobalt & HSS Drills Speeds & Feeds — feed per rev by drill diameter and material (middle of the catalog range).
ASME B94.11M twist drills: number (#1-#80) and letter (A-Z) drill sizes; drill size reference.

Material feed multipliers (aluminum 1.3×, brass 1.1×, 4140 0.85×, stainless and titanium 0.7× the mild-steel feed) are JobLine estimates. Peck guidance is JobLine shop practice. Use your drill maker's data first.

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