Here’s a good video from Black Diamond about how to use an ATC-Guide to belay on multi-pitch climbs.
How-to Video: Using the Black Diamond ATC Guide from Black Diamond Equipment on Vimeo.
There are, however, two problems with the video. The first safety issue comes from the section that details how to lower a climber while the device is in autoblocking (“Guide”) mode. I’ll detail a safer method below:
1. Clip the brake strand of the rope through a new carabiner attached to the “shelf” of the anchor.
2. Attach a friction hitch (autoblock, prussik, kleimheist) to the brake strand
3. Thread a skinny sling through the small hole on the ATC-Guide, as shown in the video.
4. Hold onto the brake strand.
5. Pull down on the skinny sling, releasing the device. This is easiest if the sling is clipped into your harness and you lean back, thus allowing you to have both hands free to control the brake strand.
6. Lower your partner.
The other issue I have with the video is that it doesn’t address what to do when you have two climbers following the pitch at the same time (i.e. you have two ropes in the device, each going to a different climber). The easiest way to prevent dropping both of the climbers simultaneously is to tie a “catastrophe knot” in the brake strand of the climber you are not going to lower. Tie the knot as close to the device as you can, then have that climber hang on the rope. This will prevent them from being dropped when you unlock the ATC-Guide to lower the other person.
Coming Soon: the danger of using an ATC-Guide (or Reverso) on traversing pitches…
