Spring-loaded camming device

When loaded, friction between an SLCD’s cams and the rock cause the cams to rotate to a larger axis thus keeping the device in place as force is applied. Because the device is initially held in place by pressure from the springs a false sense of security can be attained, since even marginal placements are created quickly and easily and may stay in position regardless of the quality of placement. Used correctly, SLCDs have the potential to provide good protection in parallel cracks, overhanging cracks, and other situations where other types of clean protection are difficult or impossible. In addition, their variable size range makes them versatile: fewer pieces will fit more places. SLCDs are manufactured with three or four cams and with flexible or rigid stems. Three cam units are generally most useful in smaller sizes which fit thin or shallow cracks. While all mechanical cams are relatively unstable, i.e. they are easily moved or dislodged from their position, three cam units are even more so, requiring careful placement and a high degree of judgement in determining their quality. All else being equal, four cam units are more stable and structurally stronger than three cams. All else being equal, SLCDs with a rigid stem are more stable when load is applied than a flexible one. All SLCDs are strongest when placed with the cams near the middle of their expansion range and when all cams are equally expanded. The holding power of all SLCDs is compromised in cracks that are dirty, snowy, or icy because the ability of the cams to hold is lessened due to decreased friction. Compared to simpler devices, SLCDs are relatively difficult to assess and can be very difficult to remove if they creep or become dislodged, even without loads being applied. In spite of their complexity, SLCDs have become overwhelmingly popular. Guides are advised, however, to study their capabilities and limitations carefully and fully understand their use and application before depending on them as the main item on their rack.