Mold-In Inserts for Plastic
Integrate strong metal threads as you make parts through injection molding. These inserts become inseparable from your parts, forming a stronger bond in plastic than heat-set inserts and press-fit inserts. Use them in a wide variety of plastic—unlike heat-set inserts, they even work in thermoset plastics, which can’t be reformed. Even with frequent use, the metal threads hold up longer than plastic threads cut directly into the material. To install, position these inserts in your mold cavity with a core pin (not included). The pin keeps plastic from flowing into the threads.
Inserts with a closed end have an extra barrier to prevent molten plastic from seeping in and clogging the threads.
Brass inserts are stronger than aluminum inserts but not as strong as 18-8 stainless steel inserts. They have good corrosion resistance.
Aluminum inserts are one-third the weight of brass and stainless steel inserts. They also have good corrosion resistance in wet environments. Since they don’t contain lead, they can be safely recycled.
18-8 stainless steel inserts are stronger than brass and aluminum inserts. They have excellent corrosion resistance, so they stand up to mild chemicals and water. Free from lead, you can safely recycle them.
For technical drawings and 3-D models, click on a part number.
Thread Size | Installed Lg. | Drill Bit Size | For Max. Hole Dia. | For Core Pin Dia. | Pkg. Qty. | Pkg. | |
Brass | |||||||
|---|---|---|---|---|---|---|---|
| 2-56 | 0.156" | No. 30 | 0.133" | 0.072" | 25 | 0000000 | 000000 |
| 4-40 | 0.187" | No. 19 | 0.169" | 0.089" | 25 | 0000000 | 00000 |
| 6-32 | 1/4" | No. 8 | 0.2" | 0.110" | 25 | 0000000 | 00000 |
| 8-32 | 0.281" | No. 1 | 0.232" | 0.136" | 25 | 0000000 | 00000 |
| 10-24 | 0.312" | H | 0.266" | 0.154" | 25 | 0000000 | 00000 |
| 10-32 | 0.312" | H | 0.266" | 0.161" | 25 | 0000000 | 00000 |
| 1/4"-20 | 0.468" | 25/64" | 0.391" | 0.204" | 25 | 0000000 | 00000 |
| 1/4"-28 | 0.468" | 25/64" | 0.391" | 0.215" | 25 | 0000000 | 00000 |
| 5/16"-18 | 0.562" | 33/64" | 0.516" | 0.261" | 10 | 0000000 | 00000 |
| 3/8"-16 | 0.687" | 14.5 mm | 0.578" | 0.318" | 5 | 0000000 | 00000 |
| 1/2"-13 | 7/8" | 49/64" | 0.766" | 0.430" | 1 | 0000000 | 0000 |
Aluminum | |||||||
| 4-40 | 0.187" | No. 19 | 0.169" | 0.089" | 25 | 0000000 | 00000 |
| 6-32 | 1/4" | No. 8 | 0.2" | 0.110" | 25 | 0000000 | 00000 |
| 8-32 | 0.38" | I | 0.272" | 0.136" | 25 | 0000000 | 00000 |
| 10-24 | 0.459" | N | 0.309" | 0.148" | 25 | 0000000 | 00000 |
| 1/4"-20 | 0.61" | 23/64" | 0.367" | 0.200" | 10 | 0000000 | 0000 |
| 5/16"-18 | 0.697" | 29/64" | 0.463" | 0.257" | 5 | 0000000 | 0000 |
18-8 Stainless Steel | |||||||
| 0-80 | 1/8" | No. 48 | 0.078" | 0.050" | 10 | 0000000 | 0000 |
| 2-56 | 1/4" | 9/64" | 0.142" | 0.072" | 25 | 00000000 | 0000 |
| 4-40 | 0.187" | No. 18 | 0.171" | 0.089" | 25 | 00000000 | 0000 |
| 6-32 | 0.219" | No. 7 | 0.202" | 0.110" | 25 | 00000000 | 00000 |
| 8-32 | 1/4" | No. 2 | 0.226" | 0.136" | 10 | 00000000 | 0000 |
| 10-24 | 0.281" | F | 0.259" | 0.154" | 10 | 00000000 | 0000 |
| 10-32 | 0.281" | F | 0.259" | 0.161" | 10 | 00000000 | 0000 |
| 1/4"-20 | 3/8" | O | 0.321" | 0.204" | 10 | 00000000 | 0000 |
| 5/16"-18 | 0.469" | Y | 0.404" | 0.261" | 5 | 00000000 | 0000 |
| 3/8"-16 | 0.562" | 29/64" | 0.466" | 0.318" | 5 | 00000000 | 00000 |
| Thread Size | Installed Lg. | Drill Bit Size | For Max. Hole Dia. | For Core Pin Dia. | Pkg. Qty. | Pkg. | |
Brass | |||||||
|---|---|---|---|---|---|---|---|
| 2-56 | 0.156" | 9/64" | 0.142" | 0.067" | 25 | 0000000 | 00000 |
| 2-56 | 0.219" | 9/64" | 0.142" | 0.067" | 25 | 0000000 | 00000 |
| 4-40 | 0.205" | No. 18 | 0.171" | 0.089" | 10 | 0000000 | 0000 |
| 4-40 | 0.281" | No. 18 | 0.171" | 0.089" | 10 | 0000000 | 0000 |
| 4-40 | 0.344" | No. 18 | 0.171" | 0.089" | 10 | 0000000 | 0000 |
| 6-32 | 1/4" | No. 7 | 0.202" | 0.104" | 25 | 0000000 | 00000 |
| 6-32 | 0.344" | No. 7 | 0.202" | 0.104" | 25 | 0000000 | 00000 |
| 6-32 | 0.469" | No. 7 | 0.202" | 0.104" | 10 | 0000000 | 0000 |
| 8-32 | 0.469" | No. 2 | 0.226" | 0.130" | 10 | 0000000 | 0000 |
| 10-24 | 0.438" | F | 0.259" | 0.145" | 10 | 0000000 | 0000 |
| 10-24 | 0.531" | F | 0.259" | 0.145" | 10 | 0000000 | 0000 |
| 10-24 | 3/4" | F | 0.259" | 0.145" | 5 | 0000000 | 00000 |
| 10-32 | 0.281" | F | 0.259" | 0.156" | 10 | 0000000 | 0000 |
| 10-32 | 0.438" | F | 0.259" | 0.156" | 10 | 0000000 | 0000 |
| 10-32 | 0.531" | F | 0.259" | 0.156" | 10 | 0000000 | 0000 |
| 1/4"-20 | 0.531" | O | 0.321" | 0.196" | 10 | 0000000 | 0000 |
| 1/4"-20 | 5/8" | O | 0.321" | 0.196" | 10 | 0000000 | 00000 |
| 5/16"-18 | 0.719" | Y | 0.404" | 0.252" | 5 | 0000000 | 0000 |
| 3/8"-16 | 0.812" | 29/64" | 0.466" | 0.307" | 5 | 0000000 | 0000 |
Aluminum | |||||||
| 8-32 | 0.38" | I | 0.272" | 0.136" | 25 | 0000000 | 00000 |
| 10-24 | 0.459" | N | 0.309" | 0.148" | 10 | 0000000 | 0000 |
| 1/4"-20 | 0.61" | 23/64" | 0.367" | 0.200" | 10 | 0000000 | 00000 |
| 5/16"-18 | 0.697" | 29/64" | 0.463" | 0.257" | 5 | 0000000 | 0000 |
18-8 Stainless Steel | |||||||
| 2-56 | 0.156" | 9/64" | 0.142" | 0.072" | 10 | 0000000 | 0000 |
| 4-40 | 0.205" | No. 18 | 0.171" | 0.089" | 10 | 0000000 | 0000 |
| 6-32 | 1/4" | No. 7 | 0.202" | 0.110" | 10 | 0000000 | 0000 |
| 8-32 | 1/4" | No. 2 | 0.226" | 0.136" | 10 | 0000000 | 0000 |
| 10-32 | 0.281" | F | 0.259" | 0.161" | 10 | 0000000 | 0000 |
| 10-32 | 0.531" | F | 0.259" | 0.154" | 10 | 0000000 | 0000 |
| 1/4"-20 | 0.344" | O | 0.321" | 0.204" | 10 | 0000000 | 0000 |
| 5/16"-18 | 0.594" | Y | 0.404" | 0.261" | 5 | 0000000 | 0000 |
| 3/8"-16 | 1/2" | 29/64" | 0.466" | 0.318" | 5 | 0000000 | 0000 |
| Thread Size | Thread Pitch, mm | Installed Lg., mm | Drill Bit Size | For Max. Hole Dia., mm | For Core Pin Dia., mm | Pkg. Qty. | Pkg. | |
Brass | ||||||||
|---|---|---|---|---|---|---|---|---|
| M2 | 0.4 | 3.96 | No. 30 | 3.37 | 1.700 | 25 | 0000000 | 000000 |
| M3 | 0.5 | 4.75 | No. 19 | 4.29 | 2.500 | 25 | 0000000 | 00000 |
| M3.5 | 0.6 | 6.35 | No. 8 | 5.08 | 3.000 | 25 | 0000000 | 00000 |
| M4 | 0.7 | 7.14 | No. 1 | 5.89 | 3.400 | 25 | 0000000 | 00000 |
| M5 | 0.8 | 7.92 | H | 6.75 | 4.300 | 25 | 0000000 | 00000 |
| M6 | 1 | 11.89 | 25/64" | 9.93 | 5.100 | 10 | 0000000 | 0000 |
| M8 | 1.25 | 14.27 | 33/64" | 13.1 | 6.800 | 5 | 0000000 | 0000 |
| M10 | 1.5 | 17.45 | 14.5 mm | 14.68 | 8.600 | 5 | 0000000 | 00000 |
| M12 | 1.75 | 22.23 | 49/64" | 19.45 | 10.300 | 5 | 0000000 | 00000 |
Aluminum | ||||||||
| M4 | 0.7 | 9.65 | I | 6.9 | 3.200 | 10 | 0000000 | 00000 |
| M5 | 0.8 | 11.65 | N | 7.85 | 4.300 | 10 | 0000000 | 00000 |
| M6 | 1 | 15.5 | 23/64" | 9.33 | 4.900 | 10 | 0000000 | 0000 |
| M8 | 1.25 | 17.7 | 29/64" | 11.75 | 6.800 | 10 | 0000000 | 00000 |
18-8 Stainless Steel | ||||||||
| M3 | 0.5 | 4.75 | No. 18 | 4.34 | 2.500 | 10 | 00000000 | 0000 |
| M4 | 0.7 | 6.35 | No. 2 | 5.74 | 3.400 | 10 | 00000000 | 0000 |
| M5 | 0.8 | 7.13 | F | 6.57 | 4.300 | 10 | 00000000 | 0000 |
| M6 | 1 | 9.53 | O | 8.15 | 5.100 | 10 | 00000000 | 0000 |
| M10 | 1.5 | 14.27 | 29/64" | 11.84 | 8.000 | 5 | 00000000 | 0000 |
| Thread Size | Thread Pitch, mm | Installed Lg., mm | Drill Bit Size | For Max. Hole Dia., mm | For Core Pin Dia., mm | Pkg. Qty. | Pkg. | |
Brass | ||||||||
|---|---|---|---|---|---|---|---|---|
| M2 | 0.4 | 4.75 | No. 30 | 3.38 | 1.700 | 25 | 0000000 | 000000 |
| M3 | 0.5 | 5.21 | No. 18 | 4.34 | 2.500 | 25 | 0000000 | 00000 |
| M3 | 0.5 | 8.74 | No. 18 | 4.34 | 2.500 | 10 | 0000000 | 0000 |
| M4 | 0.7 | 11.91 | No. 2 | 5.74 | 3.200 | 5 | 0000000 | 0000 |
| M5 | 0.8 | 13.49 | F | 6.57 | 4.300 | 10 | 0000000 | 0000 |
| M6 | 1 | 13.49 | O | 8.15 | 4.900 | 10 | 0000000 | 0000 |
| M6 | 1 | 15.88 | O | 8.15 | 4.900 | 10 | 0000000 | 00000 |
Aluminum | ||||||||
| M4 | 0.7 | 9.65 | I | 6.9 | 3.200 | 25 | 0000000 | 00000 |
| M5 | 0.8 | 11.65 | N | 7.85 | 4.300 | 10 | 0000000 | 0000 |
| M6 | 1 | 15.5 | 23/64" | 9.33 | 4.900 | 10 | 0000000 | 00000 |
| M8 | 1.25 | 17.7 | 29/64" | 11.75 | 6.800 | 5 | 0000000 | 0000 |
18-8 Stainless Steel | ||||||||
| M2.5 | 0.45 | 4.78 | No. 18 | 4.34 | 2.100 | 10 | 0000000 | 0000 |
| M3 | 0.5 | 5.21 | No. 18 | 4.34 | 2.100 | 10 | 0000000 | 0000 |
| M3.5 | 0.6 | 6.35 | No. 7 | 5.13 | 3.000 | 10 | 0000000 | 0000 |
| M4 | 0.7 | 6.35 | No. 2 | 5.74 | 3.400 | 10 | 0000000 | 0000 |
| M5 | 0.8 | 11.12 | F | 6.57 | 4.300 | 10 | 0000000 | 0000 |
| M6 | 1 | 8.73 | O | 8.15 | 5.100 | 10 | 0000000 | 0000 |
| M8 | 1.25 | 11.13 | Y | 10.26 | 6.800 | 5 | 0000000 | 0000 |
Heavy Duty Mold-In Inserts for Plastic
Add threads that resist twisting and pulling more than standard mold-in inserts. These inserts have a six-pointed shape and ridges that give ample surface area for contacting the plastic, so they’re strong and sturdy. Since plastic flows into the knurls and ridges, they form a more durable bond than heat-set and press-fit inserts, which are set after the plastic is formed. You can even mold them into phenolic and other thermoset plastics.
Made of stainless steel, they resist corrosion from mild chemicals and water. Their metal threads stay strong with frequent use, unlike plastic threads that can wear out from repeated screwing. They’re lead-free, so you can safely recycle them along with the plastic they’re installed in.
Position these inserts in the mold cavity using a core pin (not included). Remove the core pin when you open the mold, leaving the insert permanently encapsulated with threads accessible. Their closed end prevents plastic from filling the threads during molding.
For technical drawings and 3-D models, click on a part number.
| Thread Size | Installed Lg. | Drill Bit Size | Overall Dia. | For Core Pin Dia. | Pkg. Qty. | Pkg. | |
18-8 Stainless Steel | |||||||
|---|---|---|---|---|---|---|---|
| 8-32 | 0.53" | K | 0.52" | 0.130" | 10 | 0000000 | 000000 |
| 10-24 | 0.53" | K | 0.52" | 0.145" | 10 | 0000000 | 00000 |
| 10-32 | 0.53" | K | 0.52" | 0.156" | 5 | 0000000 | 0000 |
| 1/4"-20 | 0.67" | 3/8" | 0.7" | 0.196" | 5 | 0000000 | 00000 |
| 5/16"-18 | 0.83" | 12 mm | 0.91" | 0.252" | 1 | 0000000 | 0000 |
| 3/8"-16 | 0.96" | 14.5 mm | 1.04" | 0.307" | 1 | 0000000 | 0000 |
Thread-Shielding Tee Nut Inserts
Create strong threads in wood and plastic that won’t get clogged with paint or debris. These tee nut inserts have a protective plug on the bottom to block out substances during finishing processes. Four prongs on the flange grip the surrounding material to help prevent twisting. Made of 18-8 stainless steel, these inserts resist corrosion better than zinc-plated steel inserts.
To install these inserts in plastic parts, you'll need to include them in your injection molding process. Made of silicone, which is highly resistant to heat, the plug won’t melt during molding. Install these plugs in wood at any time—just hammer them into a drilled hole. Once you’ve installed an insert and completed any finishing processes, the plug is easy to remove. You can either pop it out by threading your fastener through the insert or just peel it off with your finger.
Note: The installed length includes the flange.
For technical drawings and 3-D models, click on a part number.
Barrel | Flange | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thread Size | Installed Lg. | Dia. | Lg. | Dia. | Thick. | Drill Bit Size | For Max. Hole Dia. | Features | Plug Material | Pkg. Qty. | Pkg. | |
18-8 Stainless Steel | ||||||||||||
| 1/4"-20 | 0.485" | 0.305" | 7/16" | 3/4" | 0.047" | 5/16" | 5/16" | Plug | Silicone Rubber | 10 | 000000000 | 000000 |