Signup for email deals

Exclusive savings for subscribers

 

GMT CNC Machining Feeds and Speeds Calculator



Select which GMT product you are using:

OR enter the values below:

Tool diameter (inches):
Number of Teeth/Flutes:

Calculate: Spindle Speed in Revolutions per Minute (RPM)

Cutting speed (SFM) Tool diameter Spindle speed (RPM)
÷ x 12 ÷ π =

Calculate: Cutting Speed in Surface Feet per Minute (SFM)

Spindle speed (RPM) Tool diameter Cutting speed (SFM)
x x π ÷ 12 =

Calculate: Inches per Minute Feedrate (IPM)

Spindle speed (RPM) Feed per tooth (IPT) # of Teeth/Flutes Inches per Minute Feedrate (IPM)
x x =






 

GMT Tap Drill Chart


Tap Drill Reference Chart

Aluminum, Brass & Plastics 75% Thread Stainless Steel, Steels & Iron 50% Thread Clearance Hole Drills - Close Fit Clearance Hole Drills - Free Fit
No. or Dia. # Threads Per Inch Minor Diameter Major Diameter Drill Size Decimal Equiv. Drill Size Decimal Equiv. Drill Size Decimal Equiv. Drill Size Decimal Equiv.
0 80 0.0447 0.0600 3/64 0.0469 55 0.0520 52 0.0635 50 0.0700
1 64 0.0538 0.0730 53 0.0595 1/16 0.0625 48 0.0760 46 0.0810
1 72 0.0560 0.0730 53 0.0595 52 0.0635 48 0.0760 46 0.0810
2 56 0.0641 0.0860 50 0.0700 49 0.0730 43 0.0890 41 0.0960
2 64 0.0668 0.0860 50 0.0700 48 0.0760 43 0.0890 41 0.0960
3 48 0.0734 0.0990 47 0.0785 44 0.0860 37 0.1040 35 0.1100
3 56 0.0771 0.0990 45 0.0820 43 0.0890 37 0.1040 35 0.1100
4 40 0.0813 0.1120 43 0.0890 41 0.0960 32 0.1160 30 0.1285
4 48 0.0864 0.1120 42 0.0935 40 0.0980 32 0.1160 30 0.1285
5 40 0.0943 0.1250 38 0.1015 7/64 0.1094 30 0.1285 29 0.1360
5 44 0.0971 0.1250 37 0.1040 35 0.1100 30 0.1285 29 0.1360
6 32 0.0997 0.1380 36 0.1065 32 0.1160 27 0.1440 25 0.1495
6 40 0.1073 0.1380 33 0.1130 31 0.1200 27 0.1440 25 0.1495
8 32 0.1257 0.1640 29 0.1360 27 0.1440 18 0.1695 16 0.1770
8 36 0.1299 0.1640 29 0.1360 26 0.1470 18 0.1695 16 0.1770
10 24 0.1389 0.1900 25 0.1495 20 0.1610 9 0.1960 7 0.2010
10 32 0.1517 0.1900 21 0.1590 18 0.1695 9 0.1960 7 0.2010
12 24 0.1649 0.2160 16 0.1770 12 0.1890 2 0.2210 1 0.2280
12 28 0.1722 0.2160 14 0.1820 10 0.1935 2 0.2210 1 0.2280
12 32 0.1777 0.2160 13 0.1850 9 0.1960 2 0.2210 1 0.2280
1/4 20 0.1887 0.2500 7 0.2010 7/32 0.2188 F 0.2570 H 0.2660
1/4 28 0.2062 0.2500 3 0.2130 1 0.2280 F 0.2570 H 0.2660
1/4 32 0.2117 0.2500 7/32 0.2188 1 0.2280 F 0.2570 H 0.2660
5/16 18 0.2443 0.3125 F 0.2570 J 0.2770 P 0.3230 Q 0.3320
5/16 24 0.2614 0.3125 I 0.2720 9/32 0.2812 P 0.3230 Q 0.3320
5/16 32 0.2742 0.3125 9/32 0.2812 L 0.2900 P 2.3230 Q 0.3320
3/8 16 0.2983 0.3750 5/16 0.3125 Q 0.3320 W 0.3860 X 0.3970
3/8 24 0.3239 0.3750 Q 0.3320 S 0.3480 W 0.3860 X 0.3970
3/8 32 0.3367 0.3750 11/32 0.3438 T 0.3580 W 0.3860 X 0.3970
7/16 14 0.3499 0.4375 U 0.3680 25/64 0.3906 29/64 0.4531 15/32 0.4687
7/16 20 0.3762 0.4375 25/64 0.3906 13/32 0.4062 29/64 0.4531 15/32 0.4687
7/16 28 0.3937 0.4375 Y 0.4040 Z 0.4130 29/64 0.4531 15/32 0.4687
1/2 13 0.4056 0.5000 27/64 0.4219 29/64 0.4531 33/64 0.5156 17/32 0.5312
1/2 20 0.4386 0.5000 29/64 0.4531 15/32 0.4688 33/64 0.5156 17/32 0.5312
1/2 28 0.4562 0.5000 15/32 0.4688 15/32 0.4688 33/64 0.5156 17/32 0.5312
9/16 12 0.4603 0.5625 31/64 0.4844 33/64 0.5156 37/64 0.5781 19/32 0.5938
9/16 18 0.4943 0.5625 33/64 0.5156 17/32 0.5312 37/64 0.5781 19/32 0.5938
9/16 24 0.5114 0.5625 33/64 0.5156 17/32 0.5312 37/64 0.5781 19/32 0.5938
5/8 11 0.5135 0.6250 17/32 0.5312 9/16 0.5625 41/64 0.6406 21/32 0.6562
5/8 18 0.5568 0.6250 37/64 0.5781 19/32 0.5938 41/64 0.6406 21/32 0.6562
5/8 24 0.5739 0.6250 37/64 0.5781 19/32 0.5938 41/64 0.6406 21/32 0.6562
11/16 24 0.6364 0.6875 41/64 0.6406 21/32 0.6562 45/64 0.7031 23/32 0.7188
3/4 10 0.6273 0.7500 21/32 0.6562 11/16 0.6875 49/64 0.7656 25/32 0.7812
3/4 16 0.6733 0.7500 11/16 0.6875 45/64 0.7031 49/64 0.7656 25/32 0.7812
3/4 20 0.6887 0.7500 45/64 0.7031 23/32 0.7188 49/64 0.7656 25/32 0.7812
13/16 20 0.7512 0.8125 49/64 0.7656 25/32 0.7812 53/64 0.8281 27/32 0.8438
7/8 9 0.7387 0.8750 49/64 0.7656 51/64 0.7969 57/64 0.8906 29/32 0.9062
7/8 14 0.7874 0.8750 13/16 0.8125 53/64 0.8281 57/64 0.8906 29/34 0.9062
7/8 20 0.8137 0.8750 53/64 0.8281 27/32 0.8438 57/64 0.8906 29/32 0.9062
15/16 20 0.8762 0.9375 57/64 0.8906 29/32 0.9062 61/64 0.9531 31/32 0.9688
1 8 0.8466 1.000 7/8 0.8750 59/64 0.9219 1-1/64 1.0156 1-1/32 1.0313
1 12 0.8978 1.000 15/16 0.9375 61/64 0.9531 1-1/64 1.0156 1-1/32 1.0313
1 20 0.9387 1.000 61/64 0.9531 31/32 0.9688 1-1/64 1.0156 1-1/32 1.0313
1-1/16 18 0.9943 1.0625 1.000 1.000 1-1/64 1.0156 1-5/64 1.0781 1-3/32 1.0938
1-1/8 7 0.9497 1.1250 63/64 0.9844 1-1/32 1.0313 1-9/64 1.1406 1-5/32 1.1562
1-1/8 12 1.0228 1.1250 1-3/64 1.0469 1-5/64 1.0781 1-9/64 1.1406 1-5/32 1.1562
1-1/8 18 1.0568 1.1250 1-1/16 1.0625 1-5/64 1.0781 1-9/64 1.1406 1-5/32 1.1562
1-3/16 18 1.1193 1.1875 1-1/8 1.250 1-9/64 1.1406 1-13/64 1.2031 1-7/32 1.2188
1-1/4 7 1.0747 1.2500 1-7/64 1.1094 1-5/32 1.1562 1-17/64 1.2656 1-9/32 1.2812
1-1/4 12 1.1478 1.2500 1-11/64 1.1719 1-13/64 1.2031 1-17/64 1.2656 1-9/32 1.2812
1-1/4 18 1.1818 1.2500 1-3/16 1.1875 1-13/64 1.2031 1-17/64 1.2656 1-9/32 1.2812
1-5/16 18 1.2443 1.3125 1-1/4 1.2500 1-17/64 1.2656 1-21/64 1.3281 1-11/32 1.3438
1-3/8 6 1.1705 1.3750 1-7/32 1.2187 1-17/64 1.2656 1-25/64 1.3906 1-13/32 1.4062
1-3/8 12 1.2728 1.3750 1-9/64 1.2969 1-21/64 1.3281 1-25/64 1.3906 1-13/32 1.4062
1-3/8 18 1.3068 1.3750 1-5/16 1.3125 1-21/64 1.3281 1-25/64 1.3906 1-13/32 1.4062
1-7/16 18 1.3693 1.4375 1-3/8 1.3750 1-25/64 1.3906 1-29/64 1.4531 1-15/32 1.4688
1-1/2 6 1.2955 1.5000 1-11/32 1.3437 1-25/64 1.3906 1-33/64 1.5156 1-17/32 1.5312
1-1/2 12 1.3978 1.5000 1-27/64 1.4219 1-7/16 1.4375 1-33/64 1.5156 1-17/32 1.5312
1-1/2 18 1.4318 1.5000 1-7/16 1.4375 1-29/64 1.4531 1-33/64 1.5156 1-17/32 1.5312
1-9/16 18 1.4943 1.5625 1-1/2 1.5000 1-33/64 1.5156 1-37/64 1.5781 1-19/32 1.5938
1-5/8 18 1.5568 1.6250 1-9/16 1.5625 1-37/64 1.5781 1-41/64 1.6406 1-21/32 1.6562
1-11/16 18 1.6193 1.6875 1-5/8 1.6250 1-41/64 1.6406 1-45/64 1.7031 1-23/32 1.7188
1-3/4 5 1.5046 1.7500 1-9/16 1.5625 1-5/8 1.6250 1-49/64 1.7659 1-25/32 1.7812
X

Thank You for Subscribing

You're now signed up to receive emails with the latest sales events, exclusive offers, and special announcements from glacern.com

We want to keep in touch, but only if it's helpful to you! Tell us what you like and we'll send you special offers for things that interest you!

X

Thank You for Subscribing

You're now signed up to receive emails with the latest sales events, exclusive offers, and special announcements from glacern.com

We want to keep in touch, but only if it's helpful to you! Tell us what you like and we'll send you special offers for things that interest you!