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Topic Date User

Auto-Locking belay devices 20-Nov-2007 At 8:04:48 AM pharmamatt

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On 20/11/2007 six-sevens wrote:
>IBCM9 Why not....
>Warning Science Content
>Its because when you catch a fall on a auto device the stop is over a
>much shorter period of time than a manual device which has a bit of slip.
>If you graph force versus time the area under the graph is the total energy
>absorbed. Therefore the peak force on the auto device is huge compared
>to the manual device. When the peak of the graph has a bigger number than
>the strength of the placement then that placement fails.
>Thats why.

it's not very wise to use an auto-locking device for lead belay on multipitch climbs, but for a single pitch climb (unless the gear is poor) it shouldn't be a problem especially if the belayer can give a dynamic belay (read: reduced peak force due to increased delta t)