Micro Screw Selection, Installation and Quality Control Guide

Micro screws (M0.6–M3) are critical tiny components for precision equipment. Improper selection or installation causes thread stripping, floating, fracture and assembly failure. This guide covers selection, installation and inspection standards.

1. Key Selection Points

1. Size Matching: Use exact size (M0.6/M0.8/M1.0) as designed; prefer class 6g thread accuracy. No mixing of sizes.

2. Material & Application: 304/316 stainless steel for electronics/medical; carbon steel with zinc plating for toys/home appliances; titanium alloy for high temperature/corrosion.

3. Head & Drive: Phillips/Torx for anti-slip; countersunk/flat head for space-limited assembly.

2. Installation Specifications

1. Feeding: Use rotary feeder or vacuum nozzle to avoid jamming and scratching; avoid traditional vibratory bowls for micro screws.

2. Tightening: Use high-precision electric screwdriver with torque control (0.05–0.1N·m for M0.8). Never over-tighten.

3. Sequence: Pre-turn 2–3 revolutions manually before electric tightening to ensure thread alignment.

3. Quality Inspection Standards

1. Dimension: Check with projector; tolerance for head diameter, slot depth and length ≤±0.01mm.

2. Appearance: No burrs, scratches, deformation or mixed parts; uniform surface treatment.

3. Function: Pass thread gauges; anti-loose screws need torque decay test; waterproof screws need air-tightness test.

4. Troubleshooting

• Thread Stripping: Over-torque / soft material / poor thread accuracy → Reduce torque, use high-strength material, full thread inspection.

• Floating: Too long screw / poor feeding / insufficient depth → Verify length, optimize feeding, set tightening depth.

• Fracture: Material defect / heading crack / over-load → Use qualified wire, full crack inspection, control torque.