This page covers M3 Hexalobular Socket Cheese Head Screws to ISO 14580: the full dimensional row, hole and tool sizes, proof-load data and typical applications. All values are taken from the governing standards (ISO 14580 together with ISO 273, ISO 724 and ISO 898-1 where applicable).
M3 Dimensional Row (ISO 14580)
| Size | Pitch P (mm) | a (mm) | b (mm) | Head diameter dk (mm) | dk_mean (mm) | da (mm) | Head height k (mm) | n_min (mm) | r (mm) | t_min (mm) | x (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M3 | 0.5 | 1.0 | 25.0 | 5.5 | 5.4 | 3.6 | 2.0 | 0.86 | 0.1 | 0.85 | 1.25 | 4~30 | ISO 14580 |
Spanner & Drive for M3 Hexalobular Socket Cheese Head Screws
Drive geometry for M3 Hexalobular Socket Cheese Head Screws is given by the row above; match the tool to the listed values.
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) | ≈ Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 2.2 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.
Proof Load & Strength for M3
| Tensile stress area As (ISO 724) | 5 mm² |
|---|---|
| Proof load, class 8.8 | 2.9 kN |
| Proof load, class 12.9 | 4.9 kN |
| Min. ultimate tensile load, class 8.8 | 4 kN |
Proof load = tensile stress area × the proof stress Sp of the class, per ISO 898-1 — Sp is a lower figure than the yield stress Rp0.2 and the two are not interchangeable. The stress area is computed from this size's own diameter and pitch, so a fine-pitch designation gives the fine-pitch figure. Design the joint so the working preload stays below the proof load of the class selected.
M3 Hexalobular Socket Cheese Head Screws Weight
A steel M3 hexalobular socket cheese head screws at the listed 430 mm length weighs approximately 80 g each — about 80 kg per 1,000 pieces. Stainless A2/A4 weighs roughly the same (density 7.9–8.0 g/cm³).
Actual weight varies slightly with head form, thread and finish; use this figure for freight estimation only.
Installation Tips for M3 Hexalobular Socket Cheese Head Screws
- 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.
Custom manufacturing · Made to drawing
Need hexalobular socket cheese head screws in a size this table does not list?
This page covers M3 hexalobular socket cheese head screws. Where the standard stops, the drawing takes over: fine pitches, left-hand threads, partial threading, and property classes above the catalogued grade where material and heat treatment allow. Made by cold heading or warm forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
