Dimensional data for M42 Hex Nuts, Grade C to ISO 4034, with the drive and the installation notes for this type. Values are taken from the governing standard rather than from a general machine-thread table, because this type is not selected on one.
M42 Dimensional Row (ISO 4034)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e min (mm) | Nut height m (mm) | Product grade | Reference standard |
|---|---|---|---|---|---|---|
| M42 | 4.5 | 65.0 | 71.3 | 34.0 | Grade C | ISO 4034 / DIN 555 |
Spanner & Drive for M42 Hex Nuts, Grade C
M42 Hex Nuts, Grade C have a width across flats of 65.0 mm — fit a 65.0 mm open-ended spanner or socket. Use a 6-point socket for tight clearances and to reduce rounding; for repeated assembly choose a torque wrench so the joint preload is repeatable.
Common Applications for M42 Hex Nuts, Grade C
M42 Hex Nuts, Grade C are commonly specified for structural joints, flange connections and heavy equipment foundations.
Installation Tips for M42 Hex Nuts, Grade C
- Use a 6-point socket where access allows — 12-point sockets are more prone to rounding the corners on smaller sizes.
- On flanged or serrated variants, do NOT add a separate flat washer — the flange already spreads the load and the washer can defeat the locking serrations.
- At M42 the stretch in the bolt becomes the controlling factor — for critical joints, use angle-controlled or stretch-controlled tightening instead of pure torque.
Mating Parts for M42
Pair M42 with the matching M42 bolt or screw, plus a M42 flat washer where required to distribute load on softer materials.
