from Pioneering in Town and Country
by John Sweet
published by National Council
- Scouts Canada -
These projects are extra. For the Basic Lashing Skills involved
on this page, see the Link to the Lashing page on the Pioneer Main Page. You can
also make use of the Knot Links in other pages on this Websystem
TheStrophanger
An option, instead of a bosun's chair, is to convert your lashing ropes into strops, either by using fisherman's knots or simply by slipping the free ends through the lay, as shown in the illustration.
This is built on the same general principle but with two strops and no spars. The strops should be just the right length to skim the board close to the ground without actually touching it.
The special note with this project is that the lever hitch (sometimes called the the marlinespike hitch) will only hold the strain in one direction.
One of the basic principles of pioneering with ropes is that all structures should be designed in terms of the good old triangle, which is the only geometrical shape witch cannot be distorted.
Risk of damage to nature is of utmost concern with these projects - branches that are not strong enough to support a swing, turf that should not be torn up by a chariot (Le Travois).
Ropes will stretch only so far before breaking. Keep this in mind.
What is used here is the Harvester's Hitch (sometimes called `The Rope Tackle') which is simply a method of using the rope itself to increase your pulling power. All you need, apart from the rope itself, is a secure anchorage to hold the strain - a tree, a picket, a gatepost - anything, in fact, which is up to the job and may be used without damage to itself.
The tackle is merely a half sheepshank with the free end of the rope carried round the anchorage and then dogged back through the loop. This will give you a purchase of three to one.
Shelters are fun to build. They are even better to sleep in! Practice makes perfect.
For "A" in the diagram above, both pulleys/blocks are double. The two blocks/pulleys are tied to the tree with a bowline. The rope coming from the other tree comes through the top block and down through the bottom pulley.
The rope then goes up and through the top pulley again and out to a third tree where it is tied off tight.
This system gives you greater mechanical advantage, strength and ease at getting the proper strength and setting for your swing.
For "B" in the diagram above, the pulley/block running along the line from tree to tree is set up with a branch to give something to hold on to. A separate rope will keep this block reachable when lost and stuck inbetween the two trees.
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