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Single A-Frame Bridge Pictorial

The Single A-Frame Bridge is made up of three subassemblies. Please refer to Bridge Walkways as a point of reference for two of the three of these subassemblies. The following photos will enliven the text and instructions featured in Adolph Peschke’s informative, older pioneering merit badge pamphlet. Click on the photos for larger views:

Lashing the top of the legs with a two pole shear lashing. Lashing on the ledger to the bottom of the legs. Lashing on the transom at the desired distance from the butt ends of the legs. All square lashings are lashed tightly, especially on the transom.
Captured from the 2013 Jamboree Pioneering Area
Carry the assembled A-Frame to the creek or ravine. Standup the A-Frame in the desired position. Carry over the walkways and place them on the A-Frame’s transom. Connect the underspars of the walkways to  the transom with three strop lashings.
Captured from the 2013 Jamboree Pioneering Area

Single A-Frame Bridge Materials and Instructions

Single A-Frame Bridges at the Jamboree

Single A-Frame Bridges at the Jamboree

A triumphant success—posing on their Single A-Frame Bridge
A Triumphant Success—posing on their Single A-Frame Bridge

In the Pioneering Area of the 2013 national jamboree, we put together a couple of Single A-Frame Bridge kits, so Scouts and Venturers could build this simple crossing bridge during their visit to Garden Ground Mountain. Each kit included:

  • two pre-constructed walkways
  • two 12-foot leg spars (shear legs)
  • one  5-foot transom spar
  • one 6-foot ledger spar
  • two pre-positioned anchors
  • four pioneering stakes
  • two guylines
  • five lashing ropes

Whenever a crew wanted to build a bridge, we provided an overview of the design and gave them a quick introduction to tying a rope tackle and the Japanese Mark II Square LashingWhat follows are some photo montages of the Single A-Frame bridges built from the kits during the jamboree. For larger and largest views, click on the photos once, and then once again:

Positioning their A-Frame in the ditch while preparing the guylines, and lashing the walkways to the transom.
Positioning their A-Frame in the ditch while preparing the guylines, and lashing the walkways to the transom.
Lashing the ledger tightly to the legs and putting tension  on a guyline.
Lashing the transom to the legs and putting tension on a guyline.
Positioning their A-Frame and hammering stakes in the corners of the walkways.
Lashing on the Transom
Lashing on the transom to the legs.
Lashing on the ledger and holding the A-Frame up while adjusting the height of the transom.
Lashing on the ledger and holding the A-Frame up while adjusting the height of the transom.
The shear lashing at the top of the legs, and lashing the ledger at the bottom.
The Shear Lashing at the top of the legs, and lashing the ledger at the bottom.
Lashing the A-Frame legs with a shear lashing, and lashing on the ledger.
Lashing the A-Frame legs with a Shear Lashing, and lashing on the transom.
Carrying their A-Frame to the ditch and placing the walkways on the transom.
Carrying their A-Frame to the ditch and placing the walkways on the transom.
Lashing on the transom and attaching the walkways.
Lashing on the transom and attaching the walkways.
Tightly frapping a square lashing for the transom and working together to join the walkways to the A-Frame.
Tightly frapping a Square Lashing for the transom and working together to join the walkways to the A-Frame.
Strop lashing the walkways to their A-Frame.
Strop lashing the walkways to their A-Frame.

On occasion, a pair of Scouts wanted to build a bridge, and with persistence, and the help of staff or friendly Scouter, they were able to get it done.

Dynamic Duos!
Dynamic Duos!

JAMBOREE PIONEERING AREA: BRIDGES

JAMBOREE PIONEERING AREA: MAIN PAGE

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