- 12 x spars 3.6m long
- 8 x spars 2.5m long
- 2 x spars 1.25m long
- 24 lashing lengths
- Additional lashings and spars depending on final use
Make two trestles as follows:
Use 2 x 3.6m spars for uprights, a 2.5m spar for the lower horizontal rail and a 1.25m spar for the top horizontal. Using square lashings, lash the horizontal spars approximate 1m from the ends of the uprights. (a and b)
Two 2.5m spars are used for diagonal bracing – square lash them to the trestle and use a diagonal lashing to lash their centres together. (c)
To erect the frame, fix guy ropes to the top of each trestle using a round turn and two half hitches. Stand the trestles about 2m apart and lean the tops towards each other. Make sure the tops interlock and that the top horizontal spars are together. (d)
Now lash the remaining 2.5m spars across the lower sides of the framework. These will add strength to the frame and will stop the butt ends from sliding apart. (e)
The frame will now be stable enough for someone to stand on it and lash the top section together. Either use a sheer lashing on the horizontals or a square lashing there the uprights cross.
Additional spars can be added to form a bridge.
Note: Since the design of the project the principles of Health and Safety have changed dramatically.
Caution should be exercised to assess the risks associated with this build and especially regarding possible falls from height, so handrails or belays and harnesses may be required.
To download the complete plan and design document please Click Here