When you need Hex Slotted Castle Nut (Type 1) — GB/T 6180 / ISO 7036 (Series 049) in the M3 size, the controlling values come from GB/T 6180 / ISO 7036. This page lists them in one place — pitch, head geometry, tool size and the matching hole.
M3 Dimensional Row (GB/T 6180 / ISO 7036)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Total height m (mm) | Slot width (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M3 | 0.5 | 5.5 | 6.01 | 4.0 | 1.2 | ISO 7036 / GB/T 6180 |
Spanner & Drive for M3 Hex Slotted Castle Nut (Type 1) — GB/T 6180 / ISO 7036 (Series 049)
Drive geometry for M3 Hex Slotted Castle Nut (Type 1) — GB/T 6180 / ISO 7036 (Series 049) is given by the row above; match the tool to the listed values.
Common Applications for M3 Hex Slotted Castle Nut (Type 1) — GB/T 6180 / ISO 7036 (Series 049)
M3 Hex Slotted Castle Nut (Type 1) — GB/T 6180 / ISO 7036 (Series 049) are commonly specified for paired with the same-size screws on PCB hardware, light enclosures and small-scale assemblies.
Installation Tips for M3 Hex Slotted Castle Nut (Type 1) — GB/T 6180 / ISO 7036 (Series 049)
- 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
Pair M3 with the matching M3 bolt or screw, plus a M3 flat washer where required to distribute load on softer materials.
When to Step Up or Down from M3
When the joint preload approaches the proof load of M3 class 8.8, step up to M4 class 8.8 (or move to M3 class 10.9). When the joint is over-specified, M2 often saves weight and cost without losing the safety margin.