Shear
Lashing
Comments
A sheer lashing is often used to
bind adjacent poles together. It is also a good way to reinforce a broken or
weak pole. The frapping turns used to tighten the lashing may be omitted and
replaced with wedges inserted between the poles.
A loose Sheer Lashing made around
the ends of two poles will allow the poles to be opened out and used as an
A-frame. It can also be used to form a tripod just like the Figure-of-eight
lashing.
- Lay out the poles. For most lashings you will want to lay the poles side by side with the butt ends aligned (thicker ends).
- Tie a clove hitch around one of the outside poles and secure the standing part by wrapping it around the running part (or trap it under the first turns). Note: If you only lashing two poles together it may be better to simply tie the clove hitch around both poles and pull tight.
- Pass the rope around the poles to form a first turn.
- Pulling each turn tight made a series of turns until the lashing is at least as long as the combined diameters of the two poles (usually a set of 4 to 6 turns will be sufficient).
- Tighten the lashing with a frapping turn by taking the rope down between two poles at one end of the turns. This should be difficult to do if the turns have been pulled tightly (as they should be). Bring the rope back up between the poles at the other end of the lashing and pull tight. Repeat 2 or 3 times.
- Start the second set of frapping turns by taking the rope around the center pole and frapping. Take the second set of frapping turns in the opposite direction to the first set.
- Repeat for any additional poles.
- Pass the rope once more between the poles then around one pole and tuck it under itself to form a half hitch. Pull this tight and make a second half hitch forming a clove hitch by taking the rope around the same pole and tucking it under itself.
Notes
on A-Frame Lashing
An A-frame lashing or Sheer Legs is
made in the same way as a Sheer Lashing with the lashing and frapping turns
made slightly loose so that the poles can be opened out. It is often used to
raise a boat mast or to form the legs of a rope bridge. You must take care to
ensure that the legs of the frame do not slip.
Notes
on Tripods
Take a tripod by using a
Figure-of-eight lashing on three poles. Set up the tripod by crossing the
outside poles so that the cross point of the poles is under the center pole.
This makes sure that part of the load is taken by the wood in contact.
If a symmetrical arrangement of the
poles is needed within a structure the tripod can be set up by rotating the
poles around the lashing. This means that the load is supported only by the
ropes and the joint becomes flexible and so the tripod may become unstable.
