Threaded Knurled Insert Nuts Assortment Kit of M2 M3 M4 1400-Piece

Specifications:

• Material: High-Quality Brass
• Thread Sizes: Metric M2, M3, and M4
• Total Piece Count: 1,400 pieces
• Insert Method: Heat-setting or ultrasonic embedding
• Compatibility: 3D printing filaments (PLA, PETG, ABS) and injection molded plastics
• Outer Surface: Knurled for high pull-out and torque resistance
• Storage: Compartmentalized clear plastic organizer box
• Operating Temperature Range: -40°C to +150°C (Brass material rating)

Minimum hardware to get started:

• Soldering Iron : to apply localized, controlled heat to the brass insert, allowing it to smoothly melt the surrounding plastic.
• 3D Printed Part (PLA, PETG, or ABS) : with appropriately sized pilot holes designed slightly smaller than the outer diameter of the insert to ensure a tight, secure grip. 

Safety Warnings:

• Burn Hazard: Soldering irons operate at temperatures exceeding 300°C. Never touch the brass insert while or immediately after heating.
• Ventilation Warning: Melting plastics (especially ABS) can release harmful fumes. Always heat-set inserts in a well-ventilated area.
• Over-insertion: Pushing too hard can cause the insert to push completely through thin walls. Let the heat do the work, not physical force.

Accessories
Included in the Box:

• 1,400× Brass Threaded Knurled Nuts (Assorted M2, M3, and M4 sizes)
• 1× Compartmentalized clear plastic organizer box

Frequently Asked Questions

• Is this kit compatible with PLA and PETG filaments?
  Yes, the brass inserts work perfectly with all standard 3D printing filaments including PLA, PETG, and ABS.
• Can I use these inserts in injection molded parts?
  Absolutely, they are suitable for both 3D printed and pre-molded thermoplastic enclosures.
• Do these inserts work with standard metric machine screws?
  Yes, they feature standard metric M2, M3, and M4 internal threads.
• Are these compatible with resin 3D prints?
  No, standard heat-set inserts do not work well with thermoset resins; they are specifically designed for melting thermoplastics.
• What is the maximum operating temperature for these inserts?
  The brass material itself can withstand temperatures over 150°C, limited primarily by the melting point of your plastic enclosure.
• Will the brass rust over time?
  No, brass is highly resistant to corrosion and will not rust like standard steel components.
• How much pull-out strength do these inserts provide?
  When installed correctly, the knurled outer surface provides excellent resistance to both pull-out and rotational torque.
• What size pilot hole do I need for an M3 insert?
  You generally want a pilot hole slightly smaller than the insert's outer diameter, typically around 4.0mm to 4.2mm for standard M3 inserts.
• Should I design a chamfer into my pilot hole?
  Yes, adding a small chamfer to the top of the hole helps guide the insert in perfectly straight during heating.
• Can I push the insert in from the back of the part?
  It is always best to install the insert from the direction opposite to the pulling force to maximize pull-out resistance.
• Do I need a special soldering iron tip to install these?
  While not strictly required, using a specialized flat or insert-specific tip prevents molten plastic from clogging the internal threads.
• What temperature should I set my soldering iron to?
  Set your iron to roughly 10°C to 20°C above the printing temperature of your specific plastic filament.
• Can I install these without a soldering iron?
  No, a controlled heat source like a soldering iron is required to properly melt and reflow the plastic around the knurling.