you need to span a gorge, reach an island or access a secret hide
away, then the quick and easy solution is to build a rope bridge.
PIONEERING SUSPENSION BRIDGES
are some ideas to build rope bridges at camp or on a Scout night.
simplest of the rope suspension bridges is a simple crawl rope stretched between
two anchor points. The anchor points can be two sturdy trees at either
side of the gap to be bridged. Make sure that the trees are solid and
healthy and can take the load. You need a fairly sizable rope of at
least 20mm diameter. Protect the bark with wrappings of sacking or old
canvas and tie off the rope with a
round turn and two half
hitches. For a short span the rope can be hand tensioned and then
tied off on the opposite side. For a larger span you should use block
and tackle either tied onto the rope or in the form of a 'Handy Billy"
cross the bridge correctly the person should lie face down on top of
the rope, hook one ankle onto the rope and leave the other leg hanging
straight down to lower the center of gravity for balance. Process
across the rope by pulling with both hands.
Safety Note: It is very easy to slip sideways
off the rope so always try to provide protection against this
eventuality. If the rope is far off the ground then a short safety
rope in a
the persons waist with the other end looped round the crossing rope
can be used to good effect.
suspension bridges consists of two ropes, one above the other both fixed and
tensioned as for the single Crawl Rope. The ropes should be positioned
apart by about the distance from foot to shoulder of the largest
person to use the suspension bridge. This keeps the weight between the ropes.
Process across the rope bridge by standing on the lower rope and shuffling
across whilst holding onto the upper rope.
best if this rope bridge is used to actually cross a dip or depression in
the ground so that access to the lower foot rope is not too high a
step up. If the lower rope is too near the ground then there is a
possibility of actually touching the ground at the center of the
rope bridge. See illustration below of two ropes crossing a gully.
Tip - It is better
to put more tension on the upper rope so that when persons crossing
get to the center the hand rope does not give more than the foot rope
and cause the whole bridge to turn over and dump the user off.
Similar regards to safety should be in place for this bridge as for a
single Crawl Rope.
At each end of these suspension bridges two short stocky pickets are driven into the
ground. These support the foot bridge which consists of two spars
resting on the pickets. Two longer pickets are driven in either side
of the spars at each end of the suspension bridge to prevent the spars rolling
sideways and to support the handrails. The hand rails are rope and can
be tensioned to large pegs at either end. Alternatively, the handrails
can be additional spars lashed to the upright pickets. If they are
square lashed on the outside of the pickets there is more room for
persons crossing the bridge. Alternatively, the foot bridge can
comprise of three spars (for additional width) resting on three
pickets and in either case the foot bridge spars can be lashed
together for rigidity.
the illustration, the upper picture is the layout of spars and pickets
at both ends of the suspension bridge.
MONKEY BRIDGE/ROPE BRIDGE
Main rope minimum 20mm, preferably larger
large tree - this saves having to set up two ground anchors
Sacking to save the tree bark from damage
Ground anchor of some sort - if you do it right it is hard work
billy to suit the main hawser
Four longish pioneering poles, jute and lashings
Four guy ropes and anchors per sheer leg
jute around tree. Capstan main rope around tree three times and tie
off with two half hitches.
(Three turns and two half hitches)
hawser out towards anchor where it is fed through billies and pulled
taught and tied off with round
turn and two half hitches on ground anchor. Excess hawser can be
daisy-chained for security, and/or laid in loops over the tensioned
hawser from the sheer legs towards the ground anchor.
are used to make sheer legs which are then placed under taught, but
not rigid, hawser placing sacking in the fork in the sheer legs. Sheer
legs are opened and raised. Butted into the ground and guyed off.
Note: Everything must be in a dead straight
line, or the sheer legs will flip over.
you need to do is use steps at either end of the bridges and teach how
to cross the rope bridges.
you then add further lines about a meter and a half up the upper
end of the sheer legs, parallel to the main hawser and draw them tight
using a Prussic knot on a loop and brute force you create what is
described as a Monkey Bridge. This can be stabilized further by adding
string in a V shape between the hand lines via the main hawser.
this point you will have discovered that you have positioned the sheer
legs too wide and the hand rails can only be reached by an Orangutan.
If this is the case, simply close the legs, re-guy, and retention the
hand rails need to be at least as tight as the main hawser, so the
extra leverage on the guy lines means they need to be secured to
pickets rather than tent pegs.
course the sheer legs need to be well secured and the main hawser may
need to be tightened as it stretches.