Introducing our Knurled Brass Threaded Heat Inserts
Threaded Heat Inserts for 3D Printed Parts
Heatset inserts are perfect for helping in the assembly of multiple part prints, mounting external components to your 3D printed parts such as fans, latches, and other parts, and allowing you to assemble and disassemble your creation many times without stripping threaded holes in the plastic itself.
Using a common soldering iron, easily and reversibly modified with our specialised adapter kit for these inserts, OzFDM's knurled brass threaded inserts can be embedded into your 3D-printed parts to provide a secure, strong, and durable fixture point.
With a knurled exterior that helps hold it into the plastic, and able to be heated to hundreds of degrees, these inserts are compatible with almost all FDM plastics and most resins and are designed to withstand reasonably high torqued bolts and repeated use.
Threaded Inserts Tech Specs & Sizing
Threaded Inserts are knurled brass inserts that provide an efficient and secure way to affix an item to another. With its heat-set construction, the insert maintains a secure and reliable hold for arts and crafts, furniture, and other 3D printed objects.
For easy installation set the Soldering Iron to the filament printing temperature +10° Celsius.
Small Parts. Serious Strength.
Made from high-quality brass with precision knurling, OzFDM’s threaded inserts deliver outstanding grip, heat transfer, and long-term stability across both plastic and resin components.
Designed to pair perfectly with our range of PLA+, PETG, and other 3D-printing materials, they provide reliable fastening for any project.
Whether you’re assembling enclosures, upgrading mechanical parts, or finishing functional prototypes, OzFDM’s inserts ensure your prints stay strong, secure, and professionally finished every time.
Built to Bond, Made to Last
Compatible, Reliable, and Ready to Perform
OzFDM’s brass inserts work seamlessly with a wide range of 3D printing materials, including PLA, PLA+, PETG, ABS, and Nylon.
Their precise knurled geometry and smooth surface make installation simple and alignment effortless. Designed for both high and low temperature plastics, they deliver a professional grade fastening solution that improves the strength, appearance, and durability of every print, from prototypes to production-ready parts.
Built for Strength and Longevity
Exceptional Holding Power
Every detail of OzFDM’s knurled brass threaded heat inserts is engineered for strength, consistency, and performance with each insert featuring a precisely cut knurled exterior designed to lock tightly into plastic once heat-set, forming a permanent mechanical bond that won’t loosen or shift over time.
The deep, diamond-patterned ridges bite securely into the surrounding material, preventing pull out, rotation, or slippage under pressure. This mechanical grip makes a real difference in parts that experience frequent stress or repeated assembly.
Whether you are creating a hinged enclosure, mounting a bracket, or building a mechanical fixture, the inserts hold firm through countless fastening cycles. The corrosion resistant brass construction further ensures that each thread maintains its integrity and strength even after extensive use, making them ideal for both prototyping and long-term production applications.
Perfect Fit for Every Project
OzFDM offers a complete range of insert sizes, covering everything from M2 to M8 threads (and 1/4”), giving makers full flexibility across all project types.
Whether you’re reinforcing small precision components or strengthening larger mechanical joints, there’s an option perfectly matched to your design. Each insert is produced to exact tolerances and rigorously tested to guarantee accuracy, consistency, and an easy fit straight out of the box.
The result is a dependable connection that feels professional and repeatable, without the frustration of trial and error. No matter your application or material, OzFDM’s inserts help turn simple prints into robust, ready to use components.
Professional Results, Simple Installation
Installing heat-set inserts is quick, efficient, and accessible for any maker. Heat your soldering iron to the recommended temperature and gently press the insert into a slightly undersized hole.
As the brass heats, it transfers that energy evenly through the knurled surface, softening the plastic just enough to allow a perfect, controlled embed. Once cooled, the plastic re-solidifies around the insert, locking it firmly in place.
The final result is a clean, flush, and professional looking thread that’s built for precision and durability. From simple prototypes to finished products, OzFDM inserts make it easy to achieve results that look as refined as they perform.
Brass Threaded Heat Inserts - Metric Technical Specifications
Size Chart
| Type | Length | Insert Ø | Tip Ø | Hole Ø |
| M2 Long | 3 mm | 3.5 mm | 3 mm | 3.1 mm |
| M2.5 Long | 4 mm | 4.5 mm | 3.9 mm | 4 mm |
| M3 Short | 3 mm | 4.5 mm | 3.9 mm | 4 mm |
| M3 Thick | 4 mm | 5 mm | 4.3 mm | 4.4 mm |
| M3 Long | 5.7 mm | 4.6 mm | 3.9 mm | 4 mm |
| M4 Short | 4 mm | 6 mm | 5.4 mm | 5.5 mm |
| M4 Long | 8.1 mm | 6.3 mm | 5.4 mm | 5.5 mm |
| M5 Short | 6 mm | 7 mm | 6.1 mm | 6.2 mm |
| M5 Long | 9.5 mm | 7 mm | 6.1 mm | 6.2 mm |
| M6 Short | 8 mm | 8 mm | 7 mm | 7.1 mm |
| M6 Long | 12 mm | 8 mm | 7 mm | 7.1 mm |
| M8 Long | 12 mm | 10 mm | 9 mm | 9.1 mm |
| 1/4 Long | 12.7 mm | 8 mm | 7.2 mm | 7.3 mm |