On the bench specifying M3 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 034)? This page gives the controlling dimensions for the M3 size of Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 034) (to GB/T 818 / ISO 7045).
M3 Dimensional Row (GB/T 818 / ISO 7045)
| Size | Pitch (mm) | Length L (mm) | Head diameter dk (mm) | Head height k (mm) | Cross recess | Reference standard |
|---|---|---|---|---|---|---|
| M3 | 0.5 | 20 | 5.6 | 1.8 | PH1 | ISO 7045 / GB/T 818 |
Spanner & Drive for M3 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 034)
M3 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 034) use a PH1 cross recess. Match the driver bit to the recess (Phillips PH / Pozi PZ are NOT interchangeable).
Hole Sizes for M3
| Coarse-thread pitch (ISO 724) | 0.5 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 3.4 mm |
| Tapping drill, coarse thread | 2.5 mm |
Tightening Torque for M3
| Class 8.8 (dry, ~µ 0.125) | ≈ 1.3 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 1.8 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 2.1 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Common Applications for M3 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 034)
M3 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 034) are commonly specified for electronics, PCB hardware, optical mounts and small-scale machinery.
Installation Tips for M3 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 034)
- Pozidriv (PZ) drivers ride out of Phillips (PH) recesses and vice versa — confirm the recess marking on the head before assembly.
- For automated assembly, an ACR (Anti-Cam-Out Ribs) or torx-equivalent driver gives noticeably longer bit life than plain PH.
- At M3 the joint is sensitive to over-torque — use a torque-limiting driver and check the head doesn't bury into a softer counterpart.
Mating Parts for M3
For M3, pair with a M3 hex nut (ISO 4032 / DIN 934) and, where used, a M3 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.