How Does Polyamide (Nylon) Deflashing Media Improve Surface Quality in Precision Parts?

[HengLIHong]

We're currently evaluating different deflashing media for improving the surface quality of precision-molded plastic and metal components, especially in automotive electronics and small injection-molded parts.


One candidate under consideration is polyamide (PA6) deflashing media, typically produced from antistatic polyamide monofilaments and shaped into cylindrical or hexahedral particles. We’ve observed that this media offers several operational advantages in low-pressure or robotic blasting systems.


Here are some initial observations:

• Surface Smoothness: Due to its moderate hardness (~Barcol 54–62) and non-abrasive impact, PA6 seems to minimize micro-cracks and provides a more uniform surface finish than conventional glass bead blasting.
• Thermal Resistance: With a melting point of ~220°C and HDT ~205°C, it's suitable for thermally sensitive substrates, especially soft polymers or composite housings.
• Low Dust and Reusability: PA6 appears to generate less airborne particulates, and can be recycled over multiple cycles without significant loss in geometry or performance.
• Equipment Longevity: Its lower impact energy reduces wear on nozzles and internal media channels.

Key Physical Specs:

• True Specific Gravity: 1.461–1.53 g/cm³
• Bulk Density: ~0.93–0.96 g/cm³
• Surface Resistivity: <10⁹ Ω
• Available sizes: e.g., PA-30 (0.75mm cube), PA-50 (1.27mm cube)

---

Questions to the Community:​

1. Has anyone conducted surface roughness (Ra/Rz) measurements before and after PA6 deflashing on small polymer parts?
2. How does PA6 compare with cryogenic polycarbonate media in terms of edge retention and cleaning time?
3. Are there best practices for optimizing blast pressure and media flow when using nylon for flash removal?

Any insight or empirical data from your shop floor or lab would be greatly appreciated.