Angles and vector forces are an intimate part of rigging and it’s easy to get lost in the numbers.  Heck, it can even get frustrating!  Use this simple exercise to cut out the math and get a feel for how vector forces and angles play into rigging.  The math, numbers, and vector charts can come after.

Tug-O-Angle draws on experiential learning and is a fun way to kick-off an anchor workshop as it puts a variety of concepts into perspective and provides participants with an opportunity to feel and experience forces directly.  This exercise requires a minimum of 3 people but the more the merrier.


There are multiple ways to set-up this exercise.  My preference is to have two separate lengths of rope.  Find the middle point of one of these lines and tie an eight on a bite — these are the legs for your anchor.  Tie an eight on a bite at the end of your other single line — this is your load line.  Attach your load line to your anchor line using a carabiner.  See below.


Assign an equal amount of participants to each leg of rope.  This may not look fair but that’s the fun part.  Start with the legs of the anchor at a 45° angle with the load line positioned for a straight pull.  Make sure that each leg of rope and it’s assigned participants run straight in the intended direction.

The job of those on the anchor side (left in the image above) is to be a solid and strong anchor.  Direct them to hold fast and strong with legs shoulder width apart and one leg in front of the other — they must only hold and not pull!  Check in with your anchor teams and make sure they’re ready and “bomb proof” before moving onto the load team.

The job of those on load side (right in the image above) is to apply their load to the anchor.  Direct them to start with a static pull — if the anchor side holds strong direct them to apply some dynamic pulls or shock loads.

Observe what happens and debrief with participants on both the anchor and load side.  How did it feel?  What did they notice?

Repeat the exercise increasing the angle of the anchor side to 90° then 120° and finally 180°.  What do you observe each time?


Pull from the group and debrief the overall exercise.  What conclusions can be made?

Have fun with this exercise.  Add a change of direction, throw in some pulleys, change up your anchor, etc.  Find something cool?  Let us know what you discover.

Contributed by Basil Tsimoyianis

Knotty word basics

Tying knots and hitches requires the manipulation of rope in a variety of ways. Use these basic terms when describing the process of knot building and avoid getting lost in the language of rope shapes.

rope_partsWorking end: The active end of the rope used to tie the knot.

Bight: Created by grabbing the rope and forming a tight U-turn shape.

Loop: A circle formed in a rope by crossing a bight over itself.

Twist: A loop that is rotated once more.

Standing End: The end of the rope not active in knot tying.  A rope system may have multiple standing sections/ends depending on your focus at any given time.


Tension traverses and pendulums when lowering

These techniques can prove useful in a variety of scenarios where tension, together with movement, can be used to access something that is lower and to the side of your initial anchor. These techniques are commonly used by big wall rock climbers to move from one crack to another or over a blank section of rock but can also be used for retrieving a line, rigging a banner, or positioning oneself for work – among other things.

To do a tension traverse you must have a surface in front of you to move on; the less vertical the easier.  Lower yourself off your anchor and keep your feet flat against the wall for added friction; now walk yourself across the wall and keep eyes on your target as you make your way towards it.

A climber sets up for a tension traverse on Mount Rushmore in order to retrieve a banner that had shifted due to high winds.  The red arrow marks the direction and distance of the traverse.

The farther you have to move horizontally then the higher you want the anchor you lower from to be from your intended destination.  You want the tension to help you so keep your angle small to avoid fighting additional forces and think about the distance you’re moving – including what you may swing in to if you lose purchase!  It may be easier to have a partner lower you in cases where you need to use your hands and feet to pull yourself along as you go down.

A climber fixes a line to the corner of a banner on Mount Rushmore following a tension traverse.

A climber uses a line lowered from above to retrieve the corner of a banner on Mount Rushmore following a tension traverse.

With the tension traverse complete and retrieval line fixed the climber ascends to their initial anchor and uses the fix line to haul the banner to the intended position.

With the tension traverse complete and additional line fixed for retrieval the climber ascends to their initial anchor and uses the retrieval line to haul the banner into position with a partner.

A pendulum is the dynamic version of a tension traverse.  Consider the swing and risks involved.  Do not do this in cases where obstacles and hazards exist.  Lower yourself off your anchor and stop along the same horizontal plane of your intended destination; lower yourself slightly below this point and lock off your descent. The tricky part is judging how far to lower so when in doubt start out high.  Now run back and forth across the wall until you’re able to swing past the blank section to your final destination – don’t risk taking an uncontrolled swing, anchor in and get safe.

Greenpeace Climbers deploy a banner on the face of Mount Rushmore National Memorial in Keystone, SD, on July 8, 2009. Photo: Kate Davison/Greenpeace

Warning:  Tension traverses and pendulums when lowering involve movement and this can be damaging to your rope.  Protect any edges, use rope protection, get eyes on your lines, tie stopper knots at the end of your rope(s), and assess all associated risks before proceeding.