What is a Guide Pin?

A guide pin is an often used method of maintaining consistency in a number of mechanical applications. Guide pins are used in applications that require consistency in the repetitive motion of moving parts within a mechanism. Usually machined from a hardened metal, guide pins can be made to any dimension or size depending on the mechanism or application in which they are being used. Such pins can also be modeled to become a stationary part of a chassis or otherwise immovable part, or a removable part within a mechanical application that doesn’t require the pin to be a permanent fixture.

Guide pins are often used as a means of ensuring the accuracy with which machined parts are stacked on top of one another. They may also be used as a means of correctly aligning one component of a two-part system with the other. The pin may actually come in the form of a bolt with a tapered end or even in the shape of a bullet with the corresponding piece containing metal or plasticized grommets at every contact point. The grommets would allow the guide pins to penetrate the secondary component in order to ensure the accurate configuration of the two parts being put together.

Most commonly, the guide pin is a bolt mechanism. The mechanism threads into machined holes in the part that the pin is to be integrated into. This means that full customization with any application or design is allowed.

When a guide pin is manufactured, it’s usually to customer specifications based on what the pin is being designed for. As a result, the material the pin is made out of is also directly dependent on its intended application, since some applications require stronger materials than others. Most industrial applications require that of a hardened steel or other metal. Tungsten carbide is another common material used, and one which provides structural strength as well as accurate placement of components due to its strength and durability.

Guide pins are usually machined through a lathing process, turned and cut from steel blanks and heat treated to ensure stability and strength. In cases where the pin is to hold a corresponding piece even after the materials are joined thoroughly, a grommet made from the same material as the pin is often utilized to maintain the integrity of the connection between the two components. When the guide pin used is much harder than the material the corresponding piece is fabricated out of, the guide pin can often damage the material, leaving room in the connection point for shifting.