Protection using Friends

Spring-loaded camming devices (SLCDs or “Friends”) – these are more complex active (mechanical) chocks, which are composed of multiple parts moving against each other. Pulling on the control lever causes the cams of the Friend to contract; when the Friend is placed into a rock crack and the control lever is released, the cams of the Friend expand and jam in the crack.

Set of various size friends.

Set of various size friends.

Optimal placement of a Friend in a rock crack.

Optimal placement of a Friend in a rock crack.

In keeping with this construction it therefore follows that the more you pull on the load-bearing loop of the Friend, the more the cams of the Friend expand. Therefore, the more strain is placed on a Friend, the more firmly it holds in a rock crack. It is necessary, however, to warn against placing a Friend in a crack in a completely contracted state and jammed it in this way. It will then be difficult to pull it out. In order for a Friend to be able to be withdrawn from a crack, the option must be preserved of slightly contracting it in order to complete the withdrawing manoeuvre.

Video: The cams of a Friend contract when pulling on the control lever; the Friend can then be inserted into the crack and allowed to partially expand in the selected spot. When pulling on the stem the cams of a Friend have a tendency to expand further, enabling the Friend to hold even more firmly in the crack.

More in e-book.

Title Part 3Mountaineering Methodology – Part 3 – Belaying and Rappelling

ISBN 978-80-87715-09-3

MMPublishing, 2013

Available for download from Apple iTunes (in the Books section).

For example U.S. store – link

Another countries – look on the page Download

See layout.

Another possibility is Google Play. This version is a simplified (as PDF).

Title Part 3 GPMountaineering Methodology – Part 3 – Belaying and Rappelling

ISBN 978-80-87715-14-7

MMPublishing, 2014

Available for download from Google Play.