Heli-Coil drilling data - inch
INCH - DRILLED HOLE DIMENSIONS
       Nominal                      Suggested Drill Size
      Thread size              Aluminum              Steel,Magnesium,Plastic
                              UNIFIED COARSE
1 (.073)-64                     #47 (.0785)                  #46 (.0810)
2 (.086)-56                    3/32 (.0938)                  #41 (.0960)
3 (.099)-48                     #36 (.1065)                  7/64 (.1094)
4 (.112)-40                     #31 (.1200)                  #31 (.1200)
5 (.125)-40                   3.4mm (.1339)                  #29 (.1360)
6 (.138)-32                     #26 (.1470)                  #25 (.1495)
8 (.164)-32                     #17 (.1730)                  #16 (.1770)
10 (.190)-24                   13/64 (.2031)                  #5 (.2055)
12 (.216)-24                     #1 (.2280)                   #1 (.2280)
1/4 (.2500)-20                   H (.2660)                    H (.2660)
5/16 (.3125)-18                  Q (.3320)                    Q (.3320)
3/8 (.3750)-16                   X (.3970)                    X (.3970)
7/16 (.4375)-14                29/64 (.4531)                29/64 (.4531)
1/2 (.5000)-13                 33/64 (.5156)                17/32 (.5312)
9/16 (.5625)-12                37/64 (.5781)                19/32 (.5938)
5/8 (.6250)-11                 21/32 (.6562)                21/32 (.6562)
3/4 (.7500)-10                 25/32 (.7812)                25/32 (.7812)
7/8 (.8750)-9                  29/32 (.9062)                29/32 (.9062)
1 (1.000)-8                  1-1/32 (1.0312)               1-1/32 (1.0312)
1-1/8 (1.1250)-7             1-11/64 (1.1719)              1-11/64 (1.1719)
1-1/4 (1.2500)-7             1-19/64 (1.2969)              1-19/64 (1.2969)
1-3/8 (1.3750)-6             1-27/64 (1.4219)              1-27/64 (1.4219)
1-1/2 (1.5000)-6             1-35/64 (1.5469)              1-35/64 (1.5469)
                                UNIFIED FINE
2 (.086)-64                  2.35mm (.0925)                2.35mm (.0925)
3 (.099)-56                     #37 (.1040)                   #36 (.1065)
4 (.112)-48                    3mm (.1181)                    #31 (.1200)
6 (.138)-40                     #26 (.1470)                   #25 (.1495)
8 (.164)-36                     #17 (.1730)                   #16 (.1770)
10 (.190)-32                     #7 (.2010)                  13/64 (.2031)
1/4 (.2500)-28                   G (.2610)                  6.7mm (.2638)
5/16 (.3125)-24               21/64 (.3281)                  21/64 (.3281)
3/8 (.3750)-24                25/64 (.3906)                  25/64 (.3906)
7/16 (.4375)-20               29/64 (.4531)                  29/64 (.4531)
1/2 (.5000)-20                33/64 (.5156)                  33/64 (.5156)
9/16 (.5625)-18               37/64 (.5781)                  37/64 (.5781)
5/8 (.6250)-18                41/64 (.6406)                  41/64 (.6406)
3/4 (.7500)-16                49/64 (.7656)                  49/64 (.7656)
7/8 (.8750)-14                57/64 (.8906)                  57/64 (.8906)
1 (1.000)-14                 1-1/64 (1.0156)               1-1/32 (1.0312)
1 (1.000)-12                 1-1/64 (1.0156)               1-1/32 (1.0312)
1-1/8 (1.1250)-12            1-9/64 (1.1406)               1-5/32 (1.1562)
1-1/4 (1.2500)-12            1-17/64 (1.2656)              1-9/32 (1.2812)
1-3/8 (1.3750)-12            1-25/64 (1.3906)              1-13/32 (1.4062)
1-1/2 (1.5000)-12            1-33/64 (1.5156)              1-17/32 (1.5312)
Heli-Coil thread data - inch
                       Pitch Diameter               Minor            Max.
     Nominal                                                                  Thread
                              3B         2B        Diameter         Major
    Thread Size     Min.                                                       Pitch
                             Max.       Max.     Min.     Max.     Diameter
                                      UNIFIED COARSE
1 (.073)-64         .0832    .0843      .0850    .0764    .0823      .0958     .01563
2 (.086)-56         .0976    .0989      .0996    .0899    .0961      .1117     .01786
3 (.099)-48         .1126    .1140      .1148    .1036    .1104      .1289     .02083
4 (.112)-40         .1283    .1299      .1308    .1175    .1252      .1473     .02500
5 (.125)-40         .1413    .1430      .1438    .1305    .1373      .1603     .02500
6 (.138)-32         .1583    .1601      .1611    .1448    .1527      .1817     .03125
8 (.164)-32         .1843    .1862      .1872    .1708    .1781      .2077     .03125
10 (.190)-24        .2170    .2192      .2203    .1990    .2080      .2475     .04167
12 (.216)-24        .2430    .2453      .2464    .2250    .2340      .2735     .04167
1/4 (.2500)-20      .2825    .2851      .2864    .2608    .2704      .3187     .05000
5/16 (.3125)-18     .3486    .3515      .3529    .3245    .3342      .3884     .05556
3/8 (.3750)-16      .4156    .4189      .4203    .3885    .3987      .4602     .06250
7/16 (.4375)-14     .4839    .4875      .4890    .4530    .4639      .5343     .07143
1/2 (.5000)-13      .5499    .5537      .5554    .5166    .5273      .6042     .07692
9/16 (.5625)-12     .6167    .6208      .6225    .5806    .5918      .6751     .08333
5/8 (.65250)-11     .6841    .6885      .6903    .6447    .6564      .7477     .09091
3/4 (.7500)-10      .8149    .8196      .8216    .7716    .7838      .8850     .10000
7/8 (.8750)-9       .9471    .9522      .9543    .8990    .9119     1.0247     .11111
1 (1.000)-8         1.0812   1.0868     1.0890   1.0271   1.0421    1.1681     .12500
1-1/8 (1.1250)-7    1.2178   1.2239     1.2262   1.1559   1.1730    1.3171     .14286
1-1/4 (1.2500)-7    1.3428   1.3490     1.3514   1.2809   1.2980    1.4421     .14286
1-3/8 (1.3750)-6    1.4832   1.4900     1.4926   1.4110   1.4310    1.5982     .16667
1-1/2 (1.5000)-6    1.6082   1.6151     1.6177   1.5360   1.5560    1.7232     .16667
                                       UNIFIED FINE
2 (.086)-64         .0962    .0974      .0981    .0894    .0947      .1088     .01563
3 (.099)-56         .1106    .1119      .1126    .1029    .1086      .1247     .01786
4 (.112)-48         .1256    .1271      .1279    .1166    .1229      .1419     .02083
6 (.138)-40         .1543    .1560      .1569    .1435    .1503      .1733     .02500
8 (.164)-36         .1821    .1840      .1849    .1701    .1771      .2032     .02778
10 (.190)-32        .2103    .2123      .2133    .1968    .2041      .2337     .03125
1/4 (.2500)-28      .2732    .2754      .2765    .2577    .2646      .2995     .03571
5/16 (.3125)-24     .3395    .3421      .3433    .3215    .3288      .3700     .04167
3/8 (.3750)-24      .4020    .4047      .4059    .3840    .3910      .4325     .04167
7/16 (.4375)-20     .4700    .4731      .4744    .4483    .4561      .5062     .05000
1/2 (.5000)-20      .5325    .5357      .5371    .5108    .5186      .5687     .05000
9/16 (.5625)-18     .5986    .6020      .6035    .5745    .5826      .6384     .05556
5/8 (.6250)-18      .6611    .6646      .6661    .6370    .6451      .7009     .05556
3/4 (.7500)-16      .7906    .7945      .7961    .7635    .7720      .8352     .06250
7/8 (.8750)-14      .9214    .9257      .9274    .8905    .8994      .9718     .07143
1 (1.000)-14        1.0464   1.0508     1.0527   1.0155   1.0243    1.0968     .07143
1 (1.000)-12        1.0542   1.0589     1.0608   1.0181   1.0281    1.1126     .08333
1-1/8 (1.1250)-12   1.1792   1.1841     1.1860   1.1431   1.1531    1.2376     .08333
1-1/4 (1.2500)-12   1.3042   1.3092     1.3112   1.2681   1.2781    1.3626     .08333
1-3/8 (1.3750)-12   1.4292   1.4343     1.4364   1.3931   1.4031    1.4876     .08333
1-1/2 (1.5000)-12   1.5542   1.5595     1.5615   1.5181   1.5281    1.6126     .08333
Heli-Coil drilling data - metric
                  METRIC - DRILLED HOLE DIMENSIONS
     Nominal          Minor Diameter         Suggested Drill Size
    Thread Size      Min.        Max.         Aluminum   Steel, Magnesium ,Plastic
                              METRIC COARSE
M2X0.4                2.087      2.170           2.1                2.1
M2.2x0.45             2.297      2.397           2.3               2.35
M2.5x0.45             2.597      2.697           2.55              2.65
M3x0.5                3.108      3.220           3.15               3.2
M3.5x0.6              3.630      3.755           3.7                3.7
M4x0.7                4.152      4.292           4.2               4.25
M5x0.8                5.174      5.334           5.2                5.3
M6x1                  6.217      6.407           6.25               6.3
M7x1                  7.217      7.407           7.25               7.3
M8x1.25               8.271      8.483           8.3                8.4
M10x1.5              10.324     10.560           10.5              10.5
M12x1.75             12.379     12.644           12.5              12.5
M14x2                14.433     14.733           14.5              14.5
M16x2                16.433     16.733           16.5              16.5
M18x2.5              18.541     18.896          18.75              18.75
M20x2.5              20.541     20.896          20.75              20.75
M22x2.5              22.541     22.896          22.75              22.75
M24x3                24.649     25.049          24.75              24.75
M27x3                27.649     28.049          27.75              27.75
M30x3.5              30.757     31.207            31                31
M33x3.5              33.757     34.207            34                34
M36x4                36.866     37.341            37                37
M39x4                39.866     40.341            40                40
                                METRIC FINE
M8x1                  8.217      8.407           8.25               8.3
M10x1                10.217     10.407          10.25              10.25
M10x1.25             10.271     10.483          10.25              10.25
M12x1.25             12.271     12.483          12.25              12.25
M12x1.5              12.324     12.560          12.25              12.5
M14x1.5              14.324     14.560          14.25              14.5
M16x1.5              16.324     16.560          16.25              16.5
M18x1.5              18.324     18.560          18.25              18.5
M20x1.5              20.324     20.560          20.25              20.5
M22x1.5              22.324     22.560          22.25              22.5
M18x2                18.433     18.733           18.5              18.5
M20x2                20.433     20.733           20.5              20.5
M22x2                22.433     22.733           22.5              22.5
M24x2                24.433     24.733           24.5              24.5
M27x2                27.433     27.733           27.5              27.5
M30x2                30.433     30.733           30.5              30.5
M33x2                33.433     33.733           33.5              33.5
M36x2                36.433     36.733           36.5              36.5
M39x2                39.433     39.733           39.5              39.5
M36x3                36.649     37.049            37                37
M39x3                39.649     40.049            40                40
Heli-Coil thread data - metric
  Nominal                 Pitch Diameter             Major Diameter
 Thread Size   Min.     4H Max.          5H Max.         Max.
                            METRIC COARSE
M2X0.4          2.260    2.295               2.310        2.581
M2.2x0.45       2.492    2.532               2.547        2.845
M2.5x0.45       2.792    2.832               2.847        3.145
M3x0.5          3.325    3.367               3.384        3.716
M3.5x0.6        3.890    3.940               3.959        4.354
M4x0.7          4.455    4.509               4.529        5.007
M5x0.8          5.520    5.577               5.597        6.145
M6x1            6.650    6.719               6.742        7.422
M7x1            7.650    7.719               7.742        8.422
M8x1.25         8.812    8.886               8.911        9.787
M10x1.5        10.974    11.061             11.089       12.131
M12x1.75       13.137    13.236             13.271       14.478
M14x2          15.299    15.406             15.444       16.822
M16x2          17.299    17.406             17.444       18.822
M18x2.5        19.624    19.738             19.778       21.513
M20x2.5        21.624    21.738             21.778       23.513
M22x2.5        23.624    23.738             23.778       25.513
M24x3          25.948    26.093             26.135       28.238
M27x3          28.948    29.093             29.135       31.238
M30x3.5        32.273    32.428             32.472       34.925
M33x3.5        35.273    35.428             35.472       37.925
M36x4          38.598    38.763             38.809       41.615
M39x4          41.598    41.763             41.809       44.615
                              METRIC FINE
M8x1            8.650    8.719               8.742        9.422
M10x1          10.650    10.719             10.742       11.422
M10x1.25       10.812    10.886             10.911       11.787
M12x1.25       12.812    12.898             12.926       13.787
M12x1.5        12.974    13.067             13.099       14.131
M14x1.5        14.974    15.067             15.099       16.131
M16x1.5        16.974    17.067             17.099       18.131
M18x1.5        18.974    19.067             19.099       20.131
M20x1.5        20.974    21.067             21.099       22.131
M22x1.5        22.974    23.067             23.099       24.131
M18x2          19.299    19.406             19.444       20.822
M20x2          21.299    21.406             21.444       22.822
M22x2          23.299    23.406             23.444       24.822
M24x2          25.299    25.414             25.454       26.822
M27x2          28.299    28.414             28.454       29.822
M30x2          31.299    31.414             31.454       32.822
M33x2          34.299    34.414             34.454       35.822
M36x2          37.299    37.414             37.454       38.822
M39x2          40.299    40.414             40.454       41.822
M36x3          37.948    38.093             38.135       40.238
M39x3          40.948    41.093             41.135       43.238