Diagonal lashing is a type of lashing used to bind spars or poles together, to prevent racking. It is usually applied to cross-bracing where the poles do not initially touch, but may by used on any poles that cross each other at a 45° to 90° angle. Large, semi-permanent structures may be built with a combination of square lashing, which is stronger, and diagonal lashing.
Diagonal lashing steps (see image at right);
- Begin with a timber hitch around the juncture of the two poles.
- Make three turns in each direction - tightening steadily as you go.
- Make two frapping turns, tightening the joint as much a possible.
- To end, make two half hitches
- Cinch the half hitches into a clove hitch
A lashing stick can be used to safely tighten the joint. Strength will be improved if the first turn is 90° to the timber hitch and if care is taken to lay the rope turns parallel with no crossings.