This picture shows the first stage of former construction. Four strips of 1/16in ply are glued together - very straightforward for the straight sided formers.
Below is the second stage - pieces of 1/16in balsa have been added to bring the formers up to a uniform 1/8in thickness.
The same technique was employed for the rear formers, but using 1/16in balsa for both laminations.
With the vertical diagonals passing behind the upper longeron, I couldn't work out how the various infill pieces of 3/16in balsa were supposed to fit. Were they to align with the diagonal or should they be flush with the longerons to support the covering? After consulting several clubmates on this the only thing they agreed upon was that the plan wasn't clear! In the end, I opted to keep all infill pieces inset, and fitted 1/16in ply root ribs flush with the fuselage side so that the covering material will be supported on the longerons and root ribs only.
This next series of pictures shows firstly a dry assembly of the root ribs, wing joiner and incidence keeper just to check wing alignment and then, after the fitting of the upper longerons, no.2 stringers and vertical diagonals, a second check with an aluminium tube for the carbon tube incidence keeper and the brass joiner box boxed in with ply and spruce.
Finally, the whole lot was glued in place. The plan calls for the joiner box to be wrapped with glass and epoxy but I am still undecided about this. There is potentially quite a load on the joiner bar but I struggle to imagine it applying enough bending stress on its brass joiner box for it to burst out of the spruce/ply boxing in.
Anyway, with the wing fixing finally sorted out, it was time for something completely different.
In order to fix the dimensions of the motor box, I needed to make sure that the cowl would fit in the position shown on the plan (guess who's been caught out this way before!). This meant joining the two halves of the heavy plastic (ABS?) moulding. I did wonder about joining them whilst clipped together and then cutting the flanges off afterwards. However, after due consultation, decided that it would be easier to ensure the two halves were aligned if the flanges were trimmed off before attempting to join them.
The pictures above and left show outside and inside views of the finished joint. The seam itself isn't too bad, but the joint doesn't seem to be as strong as I would have liked. I established this by the simple process of accidentally dropping it on the floor!
I was surprised how big the hole at the front is. At least it means that prop alignment is not super critical but on the other hand it does leave the motor rather visible. A dummy engine, or at least a dark baffle, may be required later.
The motor box was made from 1/8in ply, suitably fretted out. 4mm captive T nuts were fitted to the front plate which was then installed with balsa strips being used to increase the gluing area.
The prop position came out pretty well spot on. I was tempted to raise the motor a bit to improve ground clearance but in the end left it as per plan. I suppose it would look odd if it weren't in line with the cylinder blisters - which themselves don't quite line up with each other, by the way. I don't know whether this is a bit of scale detail or a moulding error.
A 3mm ply spacer, seen below, provides for fine adjustment of thrustline and prop position.
The fit of the cowling around F1 isn't perfect, but is manageable.
These last three pictures show the tidying up of the wing roots and the rubber bands used to hold the wings in place. These promise to be a bit of a fiddle to fit once the fuselage is finished and covered and I can no longer reach inside to hook the bands in place!
