The concept for this gateway originated from the bamboo version placed at one end of Peschke Field at the 2013 national jamboree. Just like the name describes, this gateway flies a banner in the middle surrounded on each side by three flags. Each side is in the shape of a standing triangular prism. If the legs of each prism were far enough apart, symmetrical, and proficiently lashed, the structure could easily be self-standing. However in this instance, we’re using long, thin, yellow pine spars with unequal diameters and with an array of curves. So for stability, the gateway definitely needs to be guyed down at the front and back (outside) legs of each side!
To sport a ten foot banner and fly six 3 x 5-foot flags, a gateway like this conceivably can span as little as 20 to 24 feet. The dimensions of the above gateway are purposely larger, employing 8-foot spars to connect the legs, separated by two 14-foot center spars, so the width is closer to 30 feet. Since this project:
- is not designed for climbing
- relies on four guy lines to keep it erect
- is fairly long and wide which can make hoisting a bit of a challenge
most of the spars can be thinner, lighter-weight pine. (Bamboo would be much better!) Naturally, the two triangular prisms should be bottom-heavy, so lash thicker, heavier connector spars at the bases of each side.
Here’s a list of materials:
- six 8-foot x 3-inch bottom leg connector spars
- twelve 8-foot x 2-inch middle and top leg connector spars
- two 14-foot x 2-1/2-inch center spars
- four 16-foot x 3-inch front and back (outside) leg spars
- two 18-foot x 3-inch middle leg spars
- eight rings or small pulleys
- eight 3-foot cords to attach rings or pulleys
- eight 40-foot x 1/4-inch braided nylon ropes for halyards
- eight lightweight carabiners for the flags and banner
- forty 15-foot x 1/4-inch manila lashing ropes
- four 6-foot straight spars for right and left front and rear flagpoles (optional)
- two 8-foot straight spars for right and left middle flagpoles (optional)
- twelve lashing ropes for round lashings to attach flagpoles to the tops of the legs (optional)
One key to building this gateway is to connect the middle and front leg of each prism shape with three leg connector spars, while both legs are lying flat on the ground. Once connected, the connector spars for the rear legs can be attached to the front and middle legs, after which the rear legs themselves can be held in position and lashed.
Another key to constructing the gateway is marking the positions on each leg, measuring up from the butt ends, where the connector spars will be lashed. The intent is to assure they’re evenly-spaced, parallel to one another and perpendicular to the legs.
After the center spars are lashed to the right and left middle legs, and when all the rings and halyards for the flags and banner are tied in the proper positions, the structure is hoisted from the back using the four guy lines attached to the outside legs of both prisms (with rolling hitches or roundturns with two half hitches), and three hauling ropes attached to the top center spar with draw hitches. Refer to:“Hoisting the Tower”
The final step before securing the guy lines to 1-1 anchors with rope tackles is to rotate each prism so that the front and back legs (outside) of each are positioned out at an equal distance from the middle legs.