Why Diamond Knurl Pattern?

Unlike straight or diagonal knurling, the diamond pattern interlocks in two perpendicular directions, eliminating axial slip and reducing surface galling - making it the preferred choice for precision fastening in robotics and medical device manufacturing.

Diamond Knurl Pattern Function

The crossing knurl geometry of a Precision Diamond Knurl Nut is created by rolling or cutting diamond-shaped teeth onto the nut face. Each tooth penetrates the contact surface during tightening like a micro-key, forming a mechanical interlock. This interlock has three performance advantages over regular fasteners:

No axial slip-knurl teeth anchor the nut laterally without friction.
Maintaining preload during dynamic vibration is crucial for robotic and outdoor equipment.
Repeatable clamping force-each assembly cycle has constant torque-to-load behaviour

These qualities make the Custom Diamond Knurl Nut a good replacement for tab washers, lock washers, and nylon-insert nuts in frequent adjustment or removal applications.

Sizes, finishes, and materials

KEY-CNC makes Precision Knurl Nuts from aluminium alloys, stainless steels, and brass with surface treatments to match your operating environment. We CNC process each nut to precise tolerances, maintaining knurl depth and pitch within ±0.02 mm during manufacturing.

Material Options

Aluminium 6061-T6 is lightweight and machineable, perfect for robotics and consumer electronics.
Aluminium 7075-T6 for aerospace and luxury sports equipment has a greater strength-to-weight ratio.
Stainless Steel 303/304-corrosion-resistant; medical device assembly standard
Brass C360-marine and electrical applications; high conductivity and corrosion resistance.

Surface Finish

Clear anodising (Type II) improves aluminium surface hardness and corrosion resistance.
Type III hard anodising provides a wear-resistant surface for high-cycle applications.
Passivation-restores stainless steel corrosion resistance after CNC machining.
Electroless nickel plating-uniform brass and steel covering in difficult situations

Thread sizes range from M3 to M24, with greater diameters available. Custom Diamond Knurl Nuts can be made to your CAD specifications, including non-standard knurl pitch, face diameter, and thickness.

CNC Machining Standards & Tolerances

As part of our integrated precision manufacturing workflow at KEY-CNC, every Precision Diamond Knurl Nut undergoes multi-axis CNC machining followed by a dedicated knurling operation. Our Shenzhen-based facility combines CNC turning and CNC milling to produce nut bodies with a surface finish of Ra 0.8 μm or better on bearing surfaces.

Specification	Detail
Thread Standard	Metric (M3–M24), UNC/UNF on request
Knurl Pitch	0.4 mm / 0.5 mm / 0.6 mm (customizable)
Outer Diameter	8 mm – 40 mm standard; larger on request
Thickness	3 mm – 20 mm (application-dependent)
Surface Roughness	Ra ≤ 0.8 μm on bearing face
Tolerance	±0.02 mm on critical dimensions
Knurl Depth	0.15 mm – 0.35 mm (application-specific)
Hardness	As per material spec; anodized surfaces up to 60 HRC

Customisation, OEM/ODM

KEY-CNC offers complete Precision Knurl Nut customisation services for OEM and ODM applications. Our engineers work with designers to optimise the knurl geometry for material, thread diameter and preload.Options for customisation：

Special thread sizes and pitches for old or proprietary assemblies

Diamond, straight or helical knurl designs for your gripping surface

Custom nut face with alphanumeric marking or brand engraving

Pilot steps and recessed sockets machined together

Machined flanges
Integration of assembly lines Special packaging, kitting and bar code labelling

Our custom CNC machined Knurl Nuts are available for customers to purchase in 7-10 business days from prototype to full scale production.

Inspection, certification of quality

Each Precision Knurl Nut batch undergoes KEY-CNC's rigors quality control. Our CNC machining services for medical and industrial clients globally follow ISO 9001:2015-aligned requirements from incoming material verification to finished product dimensional inspection.