Industrial knobs are available in a variety of materials, including plastic and metal. While plastic knobs are lightweight and inexpensive, they lack the strength of their metal counterparts.
Metal knobs are typically made of steel or a similar iron alloy. With their iron alloy-based composition, they offer a superior level of strength and durability. They can handle high-torque applications, as well as harsh environments, without degrading. If you’re looking to buy a metal knob, however, there are several things you should consider.
Style
You should consider the style when choosing a metal knob. Popular styles include ball, knurled, multi-lobed, wing and scale. Ball knobs are characterized by a round, ball-shaped handle. Knurled knobs are characterized by a raised surface pattern. Multi-lobed knobs, as the name suggests, feature multiple protruding lobes — similar to a star. Wing knobs feature a pair of protruding wings on the sides. Finally, scale knobs are instrument-based control knobs with printed scales.
Material
Not all metal knobs are made of the same material. While most of them are made of an iron alloy, they are available in different types of iron alloys. Some metal knobs are made of high-carbon or stainless steel, whereas others are made of cast iron. High-carbon steel is prized for its strength. Stainless steel, on the other hand, offers better protection against rust and corrosion. Cast iron knobs are heavy and durable.
Finish
In addition to the material, you should consider the finish when choosing a metal knob. The finish consists of a protective outer layer. Even if a metal knob is made of steel or cast iron, it may feature a finish for added protection against the elements. Common finishes for metal knobs include zinc, anodized, passivated, polished, brushed and painted.
Ergonomics
Ergonomics is something to consider when choosing a metal knob. Like all industrial knobs, metal knobs are used to control devices and machines. Once attached, you can turn them to control the device or machine on which they are installed. Some metal knobs, though, are more ergonomic than others. Knurled knobs, for instance, feature a textured surface that’s easy to grip and turn.
Mount Type
Metal knobs are available in different mount types. Some of them have a threaded stud, whereas others have a threaded hole. Metal knobs with a threaded stud essentially feature a built-in bolt. You can install them by twisting this bolt into a threaded hole on the machine or device with which you intend to use them. Metal knobs with a threaded hole have an opening at the base with interior threaded. They are designed for use with devices or machines that feature a threaded stud.