Climbing hold

A climbing hold is a shaped grip that is usually attached to a climbing wall so climbers can grab or step on it. On most walls, climbing holds are arranged in paths, called routes, by specially trained route setters. Climbing holds come in a large array of sizes and shapes to provide different levels of challenge to a climber. Climbing holds are either bolted to a wall via hex-head bolts and existing t-nuts or they are screwed on with several small screws. In extreme cases, concrete anchors may be used (if putting holds on the underside of a bridge, for example).

Early climbing holds were made from real rocks that were cast into concrete blocks; later they were rocks with holes drilled in them so they could be attached to a wall. While the feel of these holds is realistic, rock holds are heavy and can polish with heavy use. Rock holds are also difficult to manufacture.

Wood was another early hold-making material, mainly because it was inexpensive and easy to carve into various shapes. It is still used today in various forms for homemade and commercially produced hand holds. Wood holds are usually smooth and pleasant to grab, though they are difficult to wash and splintering may become a problem with age. Wolfgang Güllich made the first campus board with wooden rungs to help him train for his 9a route Action Directe. In recent years wooden holds have made a resurgence, with many companies offering wooden holds. These are usually used for steep training boards, though some climbing walls do use wooden holds alongside their resin holds

In the early days, most companies that manufactured holds used a resin mixture. Early mixtures of Polyester Resin had issues with wear and tear, often becoming chipped and cracked. The chipped or broken edge of a resin hold can often provide an unintended place to grab that can be sharp or otherwise dangerous to the climber. Because resin holds are not flexible, they will may crack if they are being tightened down on a wall that is not completely flat. Modern polyester mixes have largely overcome these problems. A final problem is the weight of resin holds. As hold sizes have grown and grown, in many cases resin has become an impractical material to use. However, using a process known as hollow-backing the weight of the hold can be dramatically reduced. Modern production methods such as hollow-backing are keeping polyester as the preferred choice for many climbing walls and hold production companies.

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Wikipedia