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Threaded Inserts for Plastic for Thermoplastics or Thermoset Plastics


Whether you are working in thermoplastic or thermoset plastic, E-Z LOK offers a threaded insert with the superior holding power you need. All E-Z LOK threaded inserts for plastic are designed for post-molding installation. Installing inserts post molding reduces the costs of moldings, cuts reject waste caused by misaligned inserts and eliminates the need to “chase” threads after molding. In addition, these threaded inserts are an ideal solution for adding machine threads to parts created through 3D printing or additive manufacturing.

E-Z LOK threaded inserts for plastic are available with inch and metric internal threads and in brass or stainless steel.

E-Z Press™ Inserts for Thermoset & Thermoplastics

E-Z Press™ Inserts for Thermoset & Thermoplastics

Simple press-in installation reduces damage caused by misaligned inserts. Install cold in cored or drilled holes. Ideal for 3D printing.

E-Z Sonic™ Ultrasonic Inserts for Thermoplastics

E-Z Sonic™ Ultrasonic Inserts for Thermoplastics

Install ultrasonically or with heat staking for a strong, post-molded installation. Tapered and straight designs.

E-Z Fin™ (Finserts) for Plastic

E-Z Fin™ (Finserts) for Plastic

Slotted design minimizes splitting and splintering, Quick and easy press-in installation. Available in three lengths.

Thermoset Plastics vs. Thermoplastics

What are the differences between thermoset plastics and thermoplastics? The main distinction is that an irreversible chemical reaction occurs during the thermosetting process of thermoset plastics, so they can only be melted and shaped once, while thermoplastics do not undergo any chemical change when molded — they can be melted down and remolded several times over if need be.

Common thermoset plastics include:

  • Fiberglass
  • Polyurethane
  • Melamine
  • Polyester
  • Urea

Common thermoplastics include:

  • Polyvinyl chloride (PVC)
  • Nylon
  • Polypropylene
  • Acrylic
  • Polyethylene

E-Z Sonic™ - Ultrasonic Inserts

If you're working with thermoplastics, you need E-Z Sonic™ ultrasonic plastic threaded inserts, which are specifically designed for use in thermoplastics. These inserts are ideal for 3D printing applications.

We offer E-Z Sonic™ ultrasonic thread inserts for plastic in two varieties: tapered and straight. Both feature knurl/groove patterns designed for optimum torque and pull out resistance. They can both also be installed with an ultrasonic horn or a heat driver.

  • Tapered E-Z Sonic™ ultrasonic insers reduce installation time, particularly in production runs, while delivering outstanding performance characteristics. These expansion inserts are offered in single and double-vane configurations for maximum design flexibility.
  • Straight E-Z Sonic™ ultrasonic inserts provide superior torque and pull out resistance, while allowing for thinner boss walls. Flush models allow for installation level with or below the material surface; flanged models are ideal for electrical connections and for additional pull out resistance in reverse installations.

E-Z Press™ Inserts

When working with thermoset plastics, it's important to use expansion plastic threaded inserts that are designed for use with these materials. E-Z Press™ inserts are designed for use with both thermoset plastics and thermoplastics.

E-Z Press™ plastic threaded inserts are available in three styles: flush, flanged and reverse slot. All varieties are designed for easy "cold" installation — simply press them into place with a rubber mallet, arbor press or other implement. Once installed, these expansion inserts compress slightly along their machined-in slots. As a fastener is threaded in, the diamond-knurl OD presses into the wall of the hole and secures the insert in place.

  • E-Z Press™ flush press inserts for plastic can be installed level with or below the surface. Brass models are available with internal threads from 0-80 and M3-M6. Stainless steel E-Z Press™ flush press inserts are available with internal threads from #2 to ⅜.
  • E-Z Press™ flanged press inserts provide a large bearing surface and are ideal for fastening terminal connectors. Brass models are available with internal threads from #2-⅜ and M3-M6. Stainless steel models are available with internal threads from #2-¼.
  • E-Z Press™ reverse slot press inserts are designed for installation from the back side of the material and to accommodate reverse screw entry for maximum pull out resistance. Brass only: internal threads from #2-¼.

Important Note: Hole size requirements may vary depending on a number of factors, including material and tools. We recommend that you test your particular application before ordering your threaded inserts for plastic. We gladly supply free samples.