Spring-loaded camming devices (SLCDs) or simply cams are essential pieces of climbing gear that are used for climbing protection. Cams, the workhorses of your rack of climbing equipment, form a safety net for your traditional climbing adventures.
Cams Revolutionized Climbing
Spring-loaded camming devices are the modern safety net for traditional climbing. Before the invention of SLCDs, climbers protected themselves by hammering pitons into cracks and then later they protected routes with various types of nuts which were wedged into cracks. In the late 1970s, climber Ray Jardine revolutionized the sport with the invention of the "Friend," the first camming device. Suddenly, parallel-sided cracks at places like Indian Creek in Utah, which until then were not protectable, opened to climbers.
Cams are Mechanical Devices
A cam is a specialized mechanical device that expands and retracts to fit inside cracks of any size, giving secure protection and anchors to leaders and belayers. Using a trigger, which is pulled with the fingers, the cam is retracted to a smaller size and placed inside a crack. When the trigger is released, the lobes of the cam expand to fit inside the crack.
Cams Adapt to the Rock
Cams are popular because they are quick and easy to place in cracks, adapt to the rock, and they offer lots of security. A well-placed cam will almost never pull out of a crack when it’s loaded as in a fall. Camming devices are easier to use than monolithic protection like nuts. You’re climbing a steep wall and getting pumped so you find a crack, whip a SLCD off your gear sling, place it in the crack, clip the rope to it and, Whew! you’re safe.
Lots of Types of Cams are Available
Lots of types and brands of SLCDs are available at your local climbing shop so the choice of cams is sometimes bewildering. There are rigid-stem cams and flexible-stem cams; huge cams for huge off-width cracks; link cams which fit lots of crack sizes; and three-cam units or TCUs for thin finger cracks.
Which SLCD’s Should You Buy?
Which SLCDs should you buy for your rack? If you’re starting out, buy a basic set of standard cams like Wild Country Friends or Black Diamond C4 Camalots. These complement a set of nuts like Stoppers and will protect almost every moderate route that you will climb. Later, as you grow as a climber, you can also expand your rack and buy specialized cams like a #4 Camalot for offwidth cracks and a set to TCUs for thin cracks.