The trestle is often used to build bridges and as a subassembly for a variety of larger pioneering projects. Two trestles can be joined by bringing the top ledgers together and interlocking them. When the trestles are leaned against one another, the weight of each helps to form one combined structure.
When uniting two trestles in this manner, the tops of the legs of one trestle need to be angled towards one another. This way, when the two trestles are brought together, the legs of one trestle will fit between the legs of the other.
The interlocking trestles for this requirement can be constructed with 5-foot Scout Staves and lashed together with 6-foot lashing ropes for the square lashings, and two 10-foot lashing ropes for the diagonal lashings.
If your class chooses to build a Single Lock Bridge, your interlocking trestles can be a class effort and constructed with the following materials and later used for that project:
- four 6-foot x 3-inch trestle legs
- four 4-foot x 2-1/2-inch trestle ledgers
- four six-foot x 2-inch cross braces
- 18 15-foot lashing ropes (1/4-inch manila)