The WACO NINE has ailerons on the upper wings only. They are operated by cables coming up from the lower wing to the control horn. When the aileron moves down the forward end of the horn moves above the fabric surface of the lower wing. To provide room for this they made a prism shaped copper box which nails to the spar and some wood framing around it.
After the NINE, WACO generally used ailerons on both wings driven by push rods in the lower wing with the upper aileron slaved by a strut to the lower one.
The joy of having a drawing to work from. IT doesn't specify what type of copper just the thickness, 0.032". I ordered some copper sheet from
OnlineMetals.com
The copper I bought is ASTM B370 roofing material. That seems appropriate since I can envision these 2 farm boys, Clayton and Sam, going to the local hardware for some copper to make these and getting a piece of roofing copper.
The drawing doesn't have a flat pattern so I drew one on poster board.
The cut piece doesn't look copper because it has some blue protector film on it. I think I could have gotten this cheaper by getting the material with the film only on one side. I punched the corner holes with a 3/32" punch. The copper is very soft and doesn't show signs of cracking in the corners after bending. I didn't know how much to allow for a bend allowance so I left the ends of the folds long enough to trim after bending.
I made a form block from some pieces of pine left over from one of the trees in my back yard. The plywood on the end is there because I made the block 1/2" short. After all my layout work I forgot the long side of the block is the hypotenuse of the triangle on this side view. All's well that ends well. The block is rectangular shaped so it's easy to clamp in the vise for bending.
I used the belt sander to put a 1/16" radius on any corners where I'll bend the copper around the block.
To get the block, copper and backing block all aligned I sat some wood, the height of the bottom fold, on both side of the copper and then just stood my blocks on the wood. It worked out better than a second set of hands. It was easy to use my free hand to squeeze on a clamp to hold it all in place.
The pointy end of the block is aligned with the holes for the end fold and the clamp installed at that end. The other end will get held in the vise while bending.
The backing block gets you a tighter corner. Always use one.
With the whole thing held in the vise, hammering on a piece of wood to form the bend gets a nice smooth tight side corner.
Repeat on the other side.
The end fold was hammered down.
Time to remove the protective film. Way too much worrying about keeping the copper shiny.
For the folds to close the box set the block on it's side, hold everything tight and hammer the flap over. In hind sight I could have made a prism shaped backing block and the fold would have been easier to get nicely even, and tight. My brain was on a plywood backing block and I couldn't figure out how to clamp it in place.
It's starting to look like a box.
I used the side of the form block and a small backing block inside to fold the tab at the tall end.
Same process for the short end but it only folds to be about on a plane with the tab at the tall end.
The tabs on the sides and tall end set on wood, 1/4" above the spar. The pointy end sets on the spar. That's why the offset at the pointy end for the side fold line.
Another backing block for the inside of the box.
It's all clamped together and the block is clamped in the vice.
The metal kept sliding when I tried hammering so I added one of the bigger clamps in the middle, not shown, and that stopped it.
Trimming at the end of the process worked great. The copper was easy to cut with snips. A quick cleanup with the belt sander and a file made for nice mounting tabs.
The whole process was repeated for the other upper wing panel. The side folds were soldered. Wash off the soldering flux with hot water and dish soap.
Now I have to build the structure to hold this in place.
I know I could have made this with aluminum, but how many times do you get to make airplane parts with copper. This is old time aviation at it's best.
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