Chockstone Forum

      Sponsored By
      ROCK
   HARDWARE

Chockstone Photography

Australian Landscape Prints

Chockstone Forum - General Discussion

General Climbing Discussion

Topic Date User

Trad Rack for Araps 4-May-2005 At 8:56:48 AM LittleMac

Message

The problem comes not from the amount of froction generated but by the angle the rope enters the device and then is twisted around the stem. The friction in a belay device is created by bending the rope in reasonably straight angles (ie no twisting) and gathers it's braking force by using tight angles. A figure eight device has the rope entering at a slight angle and is then twised around the stem (thus the twisting effect) and generates it's main braking force by twisting around the stem and via contact with a considerable amount of metal. Belay devices result in far less contact with the device, this can be eviudenced by the fact that a figure 8 wears out much quicker than belay device (in general). True some 8's are better than others but all will impart some twist on the rope, this is much less of an issue with a belay device.