Slackline

Slacklining refers to the act of walking or balancing along a suspended length of flat webbing that is tensioned between two anchors. Slacklining is similar to slack rope walking and tightrope walking. Slacklines differ from tightwires and tightropes in the type of material used and the amount of tension applied during use. Slacklines are tensioned significantly less than tightropes or tightwires in order to create a dynamic line which will stretch and bounce like a long and narrow trampoline. Tension can be adjusted to suit the user, and different webbing may be used in various circumstances. Slacklining is popular because of its simplicity and versatility; it can be used in various environments with few components.

Slacklines can be set up in two principal ways: in two sections of webbing with a tensioner or with three sections of webbing and a tensioner.

The two-section setup consists of: a long (30–100-foot, 9–30-metre) piece of two-or-one-inch (5.1 or 2.5 cm) webbing with a loop sewn on one end, allowing it to cinch tightly around a tree. The second section is typically much shorter (10 ft, 3 m) and has a similar sewn loop on one end, allowing it to cinch around a tree while the other end of this shorter piece of webbing is sewn to a ratchet. The ratchet allows these two sections of webbing to be connected and tensioned to the user's specifications.

The three-section setup consists of: a long section of webbing (30–100 ft, 9–30 m) strung tightly and connected to two shorter sections (8–12 ft, 2.5–3.5 m) that are called "tree slings" and are used as anchors on either end. The most difficult and widely discussed element of a slackline setup is the tensioning system. Common setups include simple friction methods (which can also be set up with a single section of webbing), using wraps of webbing between two carabiners, a ratchet, a comealong, a carabiner pulley system, a roped pulley system, or a commercial slackline kit.

The most common anchors for slacklines are trees. Trees greater than 12 inches (30 cm) in diameter are considered ideal in most cases. There are several very effective methods of tree protection that function on two principles: eliminating abrasion, and redistributing the load over a wider area. One of the most effective means of tree protection is a wrap of vertical blocks (1 in × 1 in (2.5 cm × 2.5 cm) cut into 6 in (15 cm) pieces) strung together by drilling a small-diameter hole through the center and running cord through them. Blocks are spaced evenly to prevent the anchor slings from contacting and abrading the outer bark, and the length of the blocks distributes the load vertically as opposed to horizontally, compressing a continuous line around the trunk. The addition of a carpet square between the block wrap and the outer bark is considered ideal among the founding community of slackliners. Many other ways to protect the tree are commonly used, such as towels, mats, cardboard, carpet and purpose-made tree protectors.

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Wikipedia