Rigging mockup copy.jpg
The image is a mock up of my method of rigging a single bay biplane.
Hi Paul, this post is probably too late for your Tiger Moth build but might be of some use in the future,
As has already been pointed out, it is best to rig a section of one wing, the same section on the other wing and alternate sections between wings.
It is possible to rig a single bay biplane with two lengths of thread per wing - three if the aircraft has double flying wires. For example a possible sequence for thread one; starting at front inboard top (FIT) location, down to front outboard bottom (FOB), leave a small loop then diagonally up (bracing wire) to top rear O/B strut (TRO), another loop, then down to the rear inboard (RIB) location.Thread two would start at front inboard bottom (FIB), up to front outboard top (FOT), loop, diagonally down (bracing wire) to rear bottom outboard (ROB), loop, then up to rear cabane.
Note The image above does not represent the threading sequence, its purpose is to describe the actual tensioning method.
To the image. The red thread represents the rigging thread, the black pieces are lengths of stretched sprue which are used as round tapered wedges to lock the rigging threads in place.
Starting at FIT the rigging thread can be tightly locked in place with the sprue wedge. At FOB the thread is nipped in place with the wedge but not too tight. The 'up' side of the loop on the bottom of the wing can be locked in place with the wedge. The top of this thread is nipped in place, the 'down-ward' part of the loop going back through the wing is locked. The end of the thread passes through the wing and is nipped with the sprue. Similarly for thread two. The reason for leaving some joins less tight is to allow the rigging tension to be adjusted by easing out the wedges and finally pulling threads taut by means of the loops and then locking in place with the wedge. No need for heat.
A small pair of pliers is useful for pulling the wedges through and a fair amount of "pull" can be applied to lock everything in place, so much so that super glue is belt and braces.
Rather long winded but hopefully of some use. I would rather rig small biplanes than scribing.
Fred H.
p.s. Thread the wedge into the hole in the same direction as the thread, It adds to the tensioning by helping to pull the thread through.
GRRR, the image has disappeared. Will try again
