scout swing

12' Scout Swing Seeing Action at a Public Scout Expo — 12′ Scout Swing Seeing Action at a Public Scout Expo

The design for this swing is not complicated, though it does present some logistical challenges. The main thing is, a working swing is going to get lots of play. Therefore, lashings need to be super tight, and the eight sturdy pioneering stakes that serve as anchors 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 inches long and 1/2 inch deep, beginning 1-1/2 inches 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-frame 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.

A Swing Boat is a fairground ride in which pairs of riders pull ropes to swing back and forth. At the national jamboree, it’s one of the pioneering area’s favorite features. Click here for more information. This is a smaller, more boy-sized version, but still lots of fun and plenty big enough.

ALL LASHINGS MUST BE VERY TIGHT! (This is an appropriate occasion to start the Japanese Mark II Square Lashing with a clove hitch in the middle of the rope around the upright, under the crossing spar, before proceeding with the wraps.)

After completed, the A-frames are stood up and held in place while other construction continues.

Build the A-frames. Using 20-foot ropes, lash two identical A-frames. The tops of the shear lashings needs to be approximately 3 feet below the tips of the 12-foot legs. (In lieu of shear lashings you might want to join the legs at the top with looser square lashings applied with the legs held at 90º after which the legs can be brought into the desired position to add the ledgers, but in doing so, make sure there won’t be too much strain applied to the top rope and the spars.) The 10-foot ledgers need to be approximately 1.5 feet above the butts of the legs. Lash on an additional 6-foot cross spar for extra support on each A-frame.

Join the A-frames together. Stand up the A-frames and holding them in place, use the remaining 12-foot spars to join them together. Lash these on as low as possible so they don’t interfere with the action of the swing.

The following steps can be carried out using an 8 to 10-foot folding step ladder or by laying the structure on its side. Either way, strong crew members will be needed to hold the spars in place.

Add the Center Spar. With a TIGHT square lashing, lash the stout 10-foot center spar to the inside of one leg of each A-frame, about 1 foot from each end where the tops intersect. This will provide a good, inward lean to the A-frames. (If you are using rope grommets with steel rings, attach them to the center spar with a prusik, about 6 inches from the legs of each A-frame.)

Tightening a Square Lashing on One of the Parallel Top Support Spars

Lash on the top support spars. Join the tops of the A frames by tightly lashing a 10-foot spar on the legs of each A-frame, about 6 inches from the tips. (It’s a good idea to start these lashings with a constrictor knot to minimize slippage during use.)

Attach the pull rope spar and pull ropes. At right angles, lash a 10-foot spar across the center for the pull ropes. About 6 inches from the ends, tightly tie a 15-foot pull rope to each end using a roundturn with two half hitches.

Attach the swing. Attach a swing rope to each end of the prepared plank with a scaffold hitch. Using a roundturn with two half hitches, tie the ends of each swing rope securely to their corresponding ring -or- directly to the center spar about 6 inches from the legs of each A-frame.

Add the guylines. Using a roundturn with two half hitches or rolling hitch, attach a 36-foot x 3/8-inch guyline to the top of each leg. (If, the structure has been on its side, it’s time to stand it completely up.)

Anchoring the Ledger with Pioneering Stakes — Anchoring the Ledgers with Pioneering Stakes

Prepare the anchors. Drive in pioneering stakes for four 1-1 anchors extending 20 feet out from the legs at 45º. Attach the corresponding guyline to each using a rope tackle. Also, drive in a stake about 6 inches in at each of the four corners so they will intersect with the A-frame ledgers. Lash each stake to the corresponding ledger with a square lashing.

Make adjustments. Level out the plank to the desired height and adjust the swing ropes so the swing hangs evenly.

Materials

6 12-foot x 4-inch spars
6 10-foot x 4-inch spars
2 6-foot x 3-inch spars
18 20-foot x 1/4-inch lashing ropes
2 36-foot x 1/2-inch swing ropes
4 36-foot x 3/8-inch guylines
12 pioneering stakes
4 tent stakes and lengths of rope or binder twine for 1-1 anchors
1 2-inch x 8-foot board (sanded and notched about 6 inches from the ends)
2 rope grommets with steel rings (optional)

Tag: scout swing

12-foot Swing Boat