Dialing in the length of your tether/ascender connection
When you’re setting up your tethers and jumars for ascending a rope (usually on a big wall), getting the correct length for the tethers is critical.
If it’s too short, you make short, choppy, inefficient strokes.
If it’s too long, you can’t easily reach your upper ascender from the rest position, and you’ll flame out your arms and abs in a few minutes.
Here's how to set your tether at the right length.
Girth hitch the tethers to your belay loop or tie in points. Clip ‘em to each ascender with a locking carabiner. Hold the ascender up vertically in front of you.
The bottom of the locking carabiner should be just about at the middle of your forehead. (See photo below)
Now, clip the ascender to your fixed rope and put full bodyweight on it. If you reach straight up, your wrist should be at the top of the ascender. This positioning ensures that you have a gentle bend in your elbow when your hand is grabbing the handle, and you can easily reach the trigger on the cam. Take the time to get this right. (In teaching this a LOT, most new aid climbers initially make their tether too long.)
Once you determine the correct connection length, mark this on your tethers. If you have adjustables, add a Sharpie pen mark. If you have traditional sewn pocket daisies, add a loop of 2mm or so cord or stout string (or burly tape like hockey tape) to the correct loop to mark it. By doing this, you set it once, and you can quickly adjust it to the right spot anytime in the future.
Note the carabiners, I‘m using: the double action, twist lock Petzl Sm’D. I think this is a great application for double action carabiners. Once you let go, you know the gate is locked. This is a crucial connection and it needs to stay secure..
