Page 730 - Iscar

USER GUIDE
TAPS UNIFIED Coarse Thread

Nominal Dimensions According to ANSI B1.1

Tap flank diameter production tolerances for ISO 2B
Nut threads limit dimensions - nut threads ANSI B1.1, 2B-3B

1/8·H Coarse Pitch Threads
Nut thread Dimensions in mm
1/2·H
H1 h3 H = 0.86603P
H 60° H1 = 5 H = 0.54127P
60° 8
1/2·H Screw 17
1/4·H 1/6·H h3 = 24 H = 0.61343P
r
3
d2 = D2 = d- H = d-0.64952P
DD2 D1 P d3 d2 d 4
d3 = d-2h3 = d-1.22687P
r = H = 0.14434P
6

Minor diameter Pitch diameter Pitch diameter
Pitch External Flank Tap tolerance 2B Nut tolerance
Nominal Dia. T.P.I Dia. Dia. Nut Screw max. max. max.
P d=D d2=D2 Min. Max.
D1 h3 2B/3B 2B 3B
UNC#1 - 64 0.397 1.854 1.598 1.425 1.367 1.610 1.623 1.598 1.664 1.646
UNC# 2 - 64 0.454 2.184 1.890 1.694 1.628 1.902 1.915 1.890 1.961 1.943
UNC#3 - 48 0.529 2.515 2.172 1.941 1.864 2.184 2.197 2.172 2.248 2.228
UNC# 4 - 40 0.635 2.845 2.433 2.156 2.065 2.446 2.459 2.433 2.517 2.494
UNC# 5 - 40 0.635 3.175 2.764 2.487 2.395 2.776 2.789 2.764 2.847 2.827
UNC# 6 - 32 0.794 3.505 2.990 2.647 2.532 3.105 3.028 2.990 3.084 3.058
UNC# 8 - 32 0.794 4.166 3.650 3.307 3.193 3.675 3.688 3.650 3.746 3.721
UNC# 10 - 24 1.058 4.826 4.138 3.680 3.528 4.163 4.176 4.138 4.247 4.219
UNC# 12 - 24 1.058 5.486 4.798 4.341 4.188 4.823 4.836 4.798 4.910 4.882
UNC 1/4" - 20 1.270 6.350 5.524 4.976 4.793 5.575 5.588 5.524 5.646 5.616
UNC 5/16" - 18 1.411 7.938 7.021 6.411 6.205 7.071 7.084 7.021 7.155 7.120
UNC 3/8" - 16 1.588 9.525 8.494 7.805 7.577 8.545 8.557 8.494 8.639 8.603
UNC 7/16" - 14 1.814 11.112 9.934 9.149 8.887 9.985 9.997 9.934 10.089 10.051
UNC 1/2" - 13 1.954 12.700 11.430 10.584 10.302 11.481 11.494 11.430 11.595 11.552
UNC 9/16" - 12 2.117 14.288 12.913 11.996 11.692 12.964 12.977 12.913 13.086 13.043
UNC 5/8" - 11 2.309 15.875 14.376 13.376 13.043 14.427 14.440 14.376 14.559 14.514
UNC 3/4" - 10 2.540 19.050 17.399 16.229 15.933 17.450 17.463 17.399 17.595 17.544
UNC 7/8" - 9 2.822 22.225 20.391 19.169 18.763 20.455 20.467 20.391 20.599 20.546
UNC 1" - 8 3.175 25.400 23.338 21.963 21.504 23.401 23.414 23.338 23.561 23.505
UNC 1 1/8" - 7 3.629 28.575 26.218 24.648 24.122 26.294 26.319 26.218 26.457 26.398
UNC 1 1/4" - 7 3.629 31.750 29.393 27.823 27.297 29.469 29.494 29.393 29.637 29.576
UNC 1 3/8" - 6 4.233 34.925 32.174 30.343 29.731 32.250 32.276 32.174 32.438 32.372
UNC 1 1/2" - 6 4.233 38.100 35.349 33.518 32.906 35.425 35.451 35.349 35.616 35.550
UNC 1 3/4" - 5 5.080 44.450 41.151 38.951 38.217 41.241 41.266 41.151 41.445 41.372
UNC 2" - 4 1/2 5.644 50.800 47.135 44.689 43.876 47.235 47.260 47.135 47.450 47.371
UNC 2 1/4" - 4 1/2 5.644 57.150 53.485 51.039 50.226 53.485 53.805 53.726
UNC 2 1/2" - 4 6.350 63.500 59.375 56.627 55.710 59.375 59.718 59.632
UNC 2 3/4" - 4 6.350 69.850 65.725 62.977 62.060 65.725 66.073 65.987
UNC 3" - 4 6.350 76.200 72.075 69.327 68.410 72.075 72.428 72.339
UNC 3 1/4" - 4 6.350 82.550 78.425 75.677 74.760 78.425 78.783 78.694
UNC 3 1/2" - 4 6.350 88.900 84.775 82.027 81.110 84.775 85.183 85.049
UNC 3 3/4" - 4 6.350 95.250 91.125 88.377 87.460 91.125 91.493 91.402
UNC 4" - 4 6.350 101.600 97.475 94.727 93.810 97.475 97.848 97.757

ISCAR
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