The Balsa USA 1/3 Scale Sopwith Pup calls for the use of silver stretch thread to be used as rigging on the outer wing struts and on the cabane struts. This rigging is independent of the flyng anf landing wires and simply forms an "X" pattern over the structure.

For example, if I am looking at the right outer wing struts there would be an "X" pattern of the thread mounted to the struts. IF you looked at each set of struts as a box, each corner has an anchor point.

Clear as mud???