TWZ Twin Inserts

Metric


Features

  • Self–aligning installation using heat.
  • Opposing helical knurls and knurled vanes provide superior pull–out and torque–out resistance.
  • Double–ended to assist automatic feeding by eliminating the need for orientation during installation.
  • Thin boss walls permit compact design.
  • Available in a wide variety of thread sizes, stud lengths and options.
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General
Insert Thread Insert Thread Code Boss D Insert Diameter P Pilot Diameter
B Hole Dia. +.004 -.000 W Wall Thickness Min.
2-56 256 .125 .051 .137 .123
4-40 440 .157 .063 .174 .154
6-32 632 .189 .071 .205 .185
8-32 832 .220 .083 .239 .218
10-24 1024 .252 .102 .269 .249
10-32 1032 .252 .102 .269 .249
1/4-20 2520 .315 .130 .333 .312
1/4-28 2528 .315 .130 .333 .312
5/16-18 3118 .378 .177 .394 .374
5/16-24 3124 .378 .177 .394 .374
3/8-16 3716 .469 .236 .485 .465
3/8-24 3724 .469 .236 .485 .465
1/2-13 5013 .630 .315 .643 .622
1/2-20 5020 .630 .315 .643 .622
  1. All dimensions are in inches and reference unless toleranced.
Insert Length
Insert Thread L Insert Length Insert Length Code
2-56 .118 118
.1552 155
4-40 .157 157
.188 188
.2242 224
6-32 .197 197
.2792 279
8-32 .157 157
.188 188
.228 288
.3192 319
10-24 10-32 .228 228
.3732 373
1/4-20 1/4-28 .269 269
.374 374
.4982 498
5/16-18 5/16-24 .4982 498
3/8-16 3/8-24 .4982 498
1/2-13 1/2-20 .6262 626
  1. All dimensions are in inches and reference unless toleranced.
  2. Preferred insert length.
  3. Custom insert lengths available by request.
Boss Design Recommendation

The TWZ Twin Zert is designed to be installed into a straight molded hole with a 0.5° inclusive taper. The top of the hole should not be countersunk or counterbored as this will decrease the insert’s performance. The recommended hole size applies at the point reached by the bottom of the insert. Molded holes should be used wherever possible as drilled holes may result in diminished performance. Minimum boss wall thicknesses shown are for reference and may vary depending on the type of plastic.

Installation
Pre-heating is the recommended installation method. The insert should be hot enough to soften the plastic without melting it to avoid flash around the top. Avoid excessive pressure that would force an insert into a hole without allowing the plastic to properly soften and flow around the insert features.