Detailed Production Process & Quality Control Standard of M0.6-M2 Micro Precision Screws

Tiny dimensional deviation during production will cause head cracking, incomplete threads, eccentricity and brittle fracture of micro screws, which will lead to assembly failure of electronic and medical devices. Conventional processing standards for large fasteners are not applicable to M0.6-M2 ultra-fine screws. Based on mass production experience, smallscrew sorts out the complete production flow and defect prevention solutions for micro screws.

1. Raw Material Precision Cutting

Materials include polished stainless steel wire, titanium alloy wire and high-carbon steel wire. Scratches on raw materials will be copied to finished products. High-speed cutting machines control blank length tolerance within ±0.01mm to avoid end surface skew, which causes head eccentricity in subsequent cold heading.

2. Cold Heading Head Forming

Cold heading determines head shape and concentricity. Hard alloy molds are adopted to reduce mold wear for tiny M0.6 screws. Precise clearance control prevents burrs and corner collapse, and equipment coaxial calibration avoids eccentric screws. Head cracking is mainly caused by impurities and excessive extrusion speed of raw materials.

3. Precision Thread Rolling

Thread rolling determines thread tightness and service life. Slow feeding prevents thread collapse and missing teeth. For M0.6~M1 screws, pitch error is controlled within 0.002mm. Go/no-go gauges are sampled regularly to adjust rolling pressure and avoid bending or slippery threads.

4. Deburring & Heat Treatment

Ultrasonic and centrifugal polishing are used for mild deburring without thread damage. Carbon steel self-tapping screws get quenching & tempering for high hardness; stainless steel and titanium alloy skip high-temperature quenching to maintain toughness. Electroplated carbon steel screws must undergo hydrogen baking to eliminate hydrogen embrittlement fracture risk.

5. Anti-Corrosion & Functional Surface Treatment

Coating thickness is strictly limited to avoid thread blockage. Stainless steel uses passivation; appearance parts adopt nickel plating; vibration-resistant screws use local nylon patch; ultra-fine M0.6 screws are forbidden to use thick anti-corrosion coating.

6. Multi-Stage Factory Inspection Standard

Three-level inspection system: automatic visual sorting removes defective products; 2D image measuring instrument detects dimensional accuracy; regular salt spray, torsion and tensile tests verify mechanical performance. Qualified screws are packed with moisture-proof vacuum packaging.

7. Common Defects & Preventive Measures

Bending screws: Uneven rolling force & blank length deviation; Thread slipping: Worn thread rolling dies; Hidden fracture: Hydrogen embrittlement of carbon steel; Loosening under vibration: Adopt precision thread plus nylon locking patch.

8. Manufacturing Advantages of smallscrew

smallscrew specializes in customized production of M0.6-M2 micro screws. We support non-standard customization according to drawings and samples, provide full inspection reports, and supply stable high-precision micro fasteners for consumer electronics, medical equipment, smart wearable devices and optical instruments.