Best suited for softer metals such as aluminum and standard grade steel, frequently knurled objects include tool handles, metal flashlights, knurled nuts, knurled control knobs, barbell bars, metal shafts, knurled winged screws, mechanical pencils and metal tubes. Knurling is particularly useful when it comes to assembling a high precision part into a hole in a low precision part when the hole does not closely match the diameter of the high precision part. Read More…
Leading Manufacturers
H & R Screw Machine Products, Inc.
Upland, CA | 231-832-2356H & R Screw Machine Products-ISO 9001-certified manufacturer of high-volume screw machine products for many industries. We also produce CNC turned parts and provide machining of customer supplied castings, forgings and stampings.

Thuro Metal Products, Inc.
Brentwood, NY | 800-238-3929It is Thuro’s mission to be the leading choice for screw machine parts, and to offer our products at the highest quality and the lowest cost. Our team members dedicate themselves to ensuring that our customers receive the perfect part on time, every time.

Pacific West America, Inc.
Calabasas, CA | 866-317-0208Based out of California, Pacific West America, Inc. (PWA) is a metal fabrication company. We focus most of our efforts on swiss screw machining, stampings, and precision parts, and our electronics division makes products such as cable assemblies, connectors, circuit boards and membrane switches. We create our products using a variety of CNC controlled machines, processes and robotics. Such processes ensure that our products have all of the qualities our customers require, such as close tolerances, high durability, complex dimensions.

SEGEPO-FSM, Inc.
Cold Spring, KY | 859-781-1400Since 1905, Fischer Special Mfg. has focused on improving and expanding our core processes, which is screw machined nuts and connectors. We produce prototypes, as well as low to high volume production, with design support. CNC secondary machining and outside services of electroplating, surface treatment and heat treating are also available. We are ISO 9001:2008 certified.

Premier Machine Products, Inc.
Kirtland, OH | 833-729-4954Premier Machine Products, Inc. has been an established, family-owned screw machine products manufacturer since 1968. We offer a wide range of screw machine products with customization options to ensure our products meet our customers' needs. We are ISO 9001:2015 certified.

Swiss Automation, Inc.
Barrington, IL | 847-381-4405Swiss Automation, Inc. was founded over 45 years ago, its first products were simple screw machine parts made on cam operated screw machines. Parts we produce today feature cross hole drilling and tapping, slot milling, polygon milling, "C" axis milling, miniature hole drilling, pickoff with complex and extensive back working, milling of non-conventional forms, eccentric and off center work.

The knurled pattern on the high precision part presses into the knurled walls of the low precision part and forges a connection that otherwise would not have been. In addition, knurling offers extensive manufacturing and repair applications that allow knurling companies to serve diverse industries such as electronics, automotive, construction, aerospace, telecommunications, fitness equipment and marine.
Most often conducted on a lathe, knurling is commonly achieved through the same automatic-feed mechanisms that are used to form screw machine products. Knurling tools are used in conjunction with the lathe and enable the embossing of the pattern. Embossing is the process of creating a three-dimensional design on a part or material.
There are four general knurling patterns: annular rings, straight, angular and diamond knurl. These knurling patterns can be used independently or in a combination. Annular rings are most often used when using a plastic mating component. While annular rings allow for easy mating, the ridges can make the components difficult to pull apart. A straight knurling pattern is also referred to as a linear knurl pattern and consists of a series of linear straight ridges. The straight ridges can also be formed into helical grooves referred to as a helical knurling pattern.
Angular knurling consists of straight ridges in an angular direction and is typically used in order to give extra traction to an external handle or other connective piece. The most common type of knurling pattern for hand grips is diamond knurl because it creates the most traction between a user's hand and the handle. A diamond knurl consists of a criss-cross pattern of ridges.