This is a simple project that is bound to get lots of play. Therefore, lashings need to be super tight, and eight sturdy pioneering stakes will serve as anchors and need to be driven solidly into the ground, perpendicular to and touching the six spars connecting the legs.
List of Materials
- six 3-1/2-inch x 12-foot spars for the legs
- one 4-inch x 12-foot spar for the crossbar
- six 3-inch x 6-foot connecting spars
- eight 3-foot pioneering stakes
- two 2-inch x 8-inch x 2-foot prepared swing seats
- four 20-foot x 1/2-inch swing ropes
- four steel rings
- four 6-foot x 5/8-inch ropes for Prusiks
- twenty 15-foot x 1/4-inch manila lashing ropes
- six 20-foot x 1/4-inch manila lashing ropes
- two single pulleys reeved with 20 feet of rope, with a small loop of rope tied to the top
- one eight-foot ladder
Though one might think this structure is built by making two simple tripods to support the crossbar, it’s MUCH better to make two A-frames, standing up vertically, supported by a third spar lashed to one leg of each A-frame, slanting down to the ground. The obvious reason is to give the crossbar maximum stability where it rests at the juncture of the two legs of each vertical A-frame.
Rig the swing seats. Attach two 20 foot swing ropes to the two swing seats, using a scaffold hitch rigged with a Bowline. In order to accommodate the swing rope with the Scaffold Hitch, the swing seats should be prepared with impressions cut on each side, 2″ long and 1/2″ deep, beginning 1-1/2″ from each end.
Attach the rings to the crossbar. Using the 6-foot ropes, tie the steel rings to the crossbar with prusiks at intervals as per the measurements reflected in the diagram.
Prepare the A-Frames. Using two 12-foot spars and one 6-foot spar, with tight square lashings, lash together two identical A-frames making sure the tips of the legs cross the same distance from the top for each. Use a 20-foot rope where the tips of the legs intersect, and 15-foot ropes at the bottom. NOTE: Make sure the 6-foot connecting spars are lashed low enough to the bottom so later on there will be plenty of room to lash them to the pioneering stakes.
Add the oblique supporting legs. About a foot or so below the top lashing on the A-frames, lash on a third 12-foot spar to one leg of each A-frame, using 20-foot ropes. These spars will be angled down, extending out to support the A-frames in their vertical positions.
Connect the legs. Stand up the A-frames so they’re in a vertical position. Connect the 12-foot oblique supporting leg to the legs of each A-frame, using the remaining 6-foot spars and eight 15-foot ropes. Again, make sure they’re lashed low enough to the ground so later on there will be plenty of room to lash them to the pioneering stakes. (If you’ll be using the pulleys to lift up the 12-foot crossbar, loop one over the top of a leg, before standing up the A-frames.)
Position the two 3-legged subassemblies. Line up both support assemblies so they are facing one another on even ground and with the A-frames 10 feet apart.
Position the crossbar. Tie one end of each pulley rope to the ends of the crossbar, and have two Scouts carefully hoist the crossbar up to near the tops of the A-frames. They must carefully hold it in place. Position the ladder so that it’s even with one A-frame, and have a strong Scout climb about four to five feet up and lift the end into the crux of one A-frame. Repeat the process on the other side of the swing.
Lash on the crossbar. Making sure the rings are properly hanging down, and the crossbar is extending out approximately one foot from each side, one Scout will climb up and tightly lash the crossbar to one of the legs of each A-frane with a 20-foot rope.
Tie on the swings. One Scout will climb up and connect the swing ropes to the rings using a roundturn with two half hitches, making sure the swings hang evenly at the desired height.
Drive in and lash on the anchors. Four pioneering stakes are driven into the ground on each side—two spaced evenly and touching the bottom of each A-frame, and one against each connecting spar, hammered in near the oblique supporting leg. After these stakes are solidly in the ground, so they cannot jiggle, lash them to the connecting spars using 15-foot ropes.
Test the swing and make any adjustments as necessary.