Threading: Coil Inserts

Coil inserts are available for UNC, UNF, and metric threads on both milled and turned parts.


MILLED PARTS

Metric threads Minimum modelled diameter (mm) Maximum modelled diameter (mm) 75% hole drill size (mm) Maximum thread depth (mm)*
M2 x 0.4 2.08 2.13 2.11 5.08
M2.5 x 0.45 >2.54 2.64 2.60 7.62
M3 x 0.5 3.10 3.24 3.18 5.08
M3.5 x 0.6 3.68 3.78 3.70 15.24
M4 x 0.7 4.15 4.33 4.20 15.24
M5 x 0.8 5.17 5.37 5.27 16.51
M6 x 1.0 6.21 6.40 6.31 16.51
M8 x 1.25 8.27 8.48 8.38 25.40
M10 x 1.5 10.32 10.55 10.44 25.40
M12 x 1.75 12.38 12.64 12.51 25.40
*Obstruction by other features of your part, lead-in treatments, or fixturing requirements may reduce the maximum depth of threads.
UNC threads Minimum modelled diameter (in.) Maximum modelled diameter (in.) 75% hole drill size (in.) Maximum thread depth (in.)*
#2-56 0.089 0.096 0.094 0.30
#3-48 0.105 0.110 0.107 0.40
#4-40 0.117 0.125 0.120 0.40
#5-40 0.130 0.137 0.134 0.40
#6-32 0.145 0.152 0.147 0.60
#8-32 0.170 0.178 0.173 0.60
#10-24 0.199 0.208 0.203 0.65
#12-24 0.225 0.234 0.228 0.65
1/4-20 0.260 0.270 0.266 0.65
5/16-18 0.324 0.334 0.332 1.00
3/8-16 0.388 0.398 0.397 1.00
7/16-14 0.453 0.463 0.453 1.00
1/2-13 0.515 0.531 0.522 1.00
*Obstruction by other features of your part, lead-in treatments, or fixturing requirements may reduce the maximum depth of threads.
UNF threads Minimum modelled diameter (in.) Maximum modelled diameter (in.) 75% hole drill size (in.) >Maximum thread depth (in.)*
#2-64 0.089 0.095 0.093 0.30
#3-56 0.102 0.104 0.104 0.30
#4-48 0.116 0.123 0.120 0.40
#6-40 0.144 0.150 0.147 0.60
#8-36 0.170 0.177 0.173 0.60
#10-32 0.196 0.204 0.201 0.65
1/4-28 0.257 0.265 0.261 >0.65
5/16-24 0.321 0.329 0.325 1.00
3/8-24 0.384 0.391 0.388 1.00
7/16-20 0.448 0.456 0.452 1.00
1/2-20 0.510 0.519 0.515 1.00
*Obstruction by other features of your part, lead-in treatments, or fixturing requirements may reduce the maximum depth of threads.

TURNED PARTS

Metric threads Minimum modeled diameter (mm) Maximum modeled diameter (mm) 75% hole drill size (mm) Maximum thread depth (mm)
M2.5 x 0.45 2.59 2.69 2.65 7.62
M3 x 0.5 3.10 3.24 3.18 10.16
M3.5 x 0.6 3.68 3.78 3.70 10.16
M4 x 0.7 4.15 4.33 4.20 10.16
M5 x 0.8 5.17 5.37 5.27 10.16
M6 x 1.0* 6.21 6.40 6.31 12.70
M8 x 1.25* 8.27 8.48 8.38 12.70
*On-axis holes only
UNC threads Minimum modeled diameter (in.) Maximum modeled diameter (in.) 75% hole drill size (in.) Maximum thread depth (in.)
#4-40 0.085 0.094 0.089 0.30
#5-40 0.098 0.106 0.102 0.30
#6-32 0.105 0.114 0.109 0.40
#8-32 0.130 0.139 0.135 0.40
#12-24* 0.171 0.181 0.176 0.50
1/4-20* 0.196 0.207 0.202 0.50
*On-axis holes only
UNF threads Minimum modeled diameter (in.) Maximum modeled diameter (in.) 75% hole drill size (in.) Maximum thread depth (in.)
#2-64 0.089 0.095 0.093 0.30
#3-56 0.102 0.109 0.106 0.30
#4-48 0.116 0.123 0.120 0.40
#6-40 0.144 0.150 0.147 0.40
#8-36 0.170 0.177 0.173 0.40
#10-32 0.196 0.204 0.201 0.40
1/4-28* 0.257 0.265 0.261 0.50
5/16-24* 0.321 0.329 0.325 0.50
3/8-24* 0.384 0.391 0.388 0.50
7/16-20* 0.448 0.456 0.452 0.50
1/2-20* 0.510 0.519 0.515 0.50
*On-axis holes only