The layout work is done on the 2 new rear wing spars.
The ailerons have 2 spars, like the wings. The WACO NINE has ailerons on the upper wing panels only. They must Not have worked well on the 1925 version, because in 1926, with the Improved NINE, they made them longer with an Elephant Ear balance tab. The longer ailerons would have had more power and the balance tabs would lightened the stick forces.
On the 1927 Model TEN they got rid of the Elephant Ears ears and added ailerons on the lower wings.
On the NINE the ailerons are operated by cable routed through the lower wings to pulleys hidden in the structure below the aileron control horn. You can see one in front of the aft strut and one behind it.
On the TEN they used push rods to operate the lower ailerons with the upper ailerons slaved to them by a strut between the Ailerons.
The aileron starts about 1/3 of the way along the spar and extends about 18" beyond the tip.
Each aileron is hinged with 4 hinges using an Eye Bolt and Fork Bolt arrangement. The fork bolt part bolts through the aft wing spar. The eye bolt part bolts through the forward aileron spar. I have 4 drawings showing the location of the aileron hinges, the wing assembly drawing, the aft spar drawing, the aileron drawing, and an older aileron drawing from 1926. They all have slightly different dimensions. There are more of these anomalies. The aileron drawing shows the length of the forward spar is 120" but the Bill of Materials on the same drawing shows 120 1/4".
To resolve these things I've modeled the aileron in TurboCAD. I'm using the dimensions from the drawings which work in the model.
I have all the ribs and hole locations drawn out on both sides of each spar. I also write on the spars the size of any drilled holes.
I'll match drill the hinge bolt holes in each aileron spar by using it's wing spar as the master for the holes in the aileron spar. Even if I measure slightly wrong the hinges won't bind.
The tip of the forward spar has a tapered tip with a gentle Ogee type curve connection the taper to the main straight section. To layout the curves in this 8" section I clamped 2 blocks to the spar.
The one on the left is clamped flush with the straight edge, with the corner at the start of the curve. The other block is clamped so it's edge follows the taper, with its corner at the start of the curve.
I clamped my Starrett meter scale to the edges of these 2 blocks and drew the curve between them. The clamps should be at the end of each block so the curve is tangent to the 2 blocks. It was easier to do than explain.
The drawing doesn't show the taper on the aft spar so I made it such that where each rib crosses the 2 spars are the same height. At the inboard rib the spars are 1 13/32" tall and at the outboard rib they are 1" tall.
I'm ready to start drilling, routing, etc. We're making parts again!
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