Hi Jimmy, Happy New Year!!
I've moved along today as I marked out the three wing sections onto the 12mm by 4mm spruce spar and then cut the spar into the three required pieces.
I found a front projection drawing of a Lancaster from which to take the outer wing panel dihedral angle and cut the four ply plates to the correct angle. It's actually quite an angle.
I've found it easier to set the spar and angle plates together correctly if I cyano the plate on one side of the join while clamping the join between pliers and then add the other side plate with an epoxy resin bond. That way the correct angle is quickly set and it won't change while the epoxy sets hard.
That's the spar out of the way apart from carving the tip taper onto it . I think I'll keep a full depth spar until after the outer motor nacelle and then taper to the tip.
Need to get hold of some foam now for the wing cores.