M42 nut dimensions or sizes are critical for industrial turbine assembly, bridge pier anchoring, and heavy-duty maritime engineering. This size is specifically engineered to mate with fasteners having a 42.00 mm nominal diameter and is available in M42 x 4.5 for the coarse series.
This charts covers both the Regular Series (DIN 934 / ISO 4032) for standard load-bearing applications and the Thin or Half Series (DIN 439 / ISO 4035), which is ideal for jam nut or lock nut configurations or applications with limited vertical clearance. The thread dimensions comply with DIN 13-1 (coarse) and ISO 68-1 standards to ensure a precise fit and reliable engagement across high-capacity industrial metric fastening systems.
Disclaimer: Actual dimensions, including the width across flats (spanner or wrench size), nut height, and thread tolerance may vary depending on the specific manufacturing class and material — always verify with the official product datasheet before use or buying.
What size wrench or spanner do I need for an M42 nut?
An M42 hex nut typically requires a 65 mm wrench or socket. The standard width across flats (s) for an M42 nut is 65.00 mm. Due to the extreme torque requirements—often reaching several thousand Newton-meters—hydraulic torque wrenches or industrial planetary gear multipliers are standard for installation.
What is a jam nut?
A jam nut is a low-profile hex nut, typically from the Thin Series (DIN 439), that is used to lock a standard nut in place. By tightening a standard nut against a jam nut, you create internal tension between the threads of both nuts and the bolt. This “jams” the assembly together, providing a mechanical lock that prevents loosening caused by vibration or rotation.
Can a Thin Series nut handle the same torque as a Regular nut?
No. Because the Thin Series has fewer threads in contact with the bolt, it has a lower proof load. Subjecting an M42 thin nut to the high clamping forces required in structural or industrial joints is likely to result in thread stripping. For primary structural support, always use a Regular Series nut.
