Hi Tim,
You're on the right track with how things work. The buck was built for fitting my body panels and determining the shapes and placement of the support structure (this may be backwards in regard to how the original "specials" were built). Once I get the body shaped I will use the buck to make structural templates and then shape those out of aluminum as well with some steel reinforcements/framing.
First I make a paper template and lay that out on sheet aluminum.
I then cut my rough shape out of aluminum.
On the seat I used my knees, elbows and anything in the barn that had a shape resembling what I wanted (i.e. pipes, workbench corners, etc) to shape the piece of aluminum. Here is a rough idea, you can see the bends are not symmetrical but everything comes into shape as you work the metal.
Then I use the wheel to create my crown for the seat area and give the backrest and bolsters some character. This seat will have a simple tube framing, reminiscent of what they used in this era (late 40's early 50's). The seat has been further cut down and shaped out more since this picture.
Here are a few pictures of a rare Rometsch racer from the same era.
This shows more of the way things are constructed.
