Over the years I have often been asked why I prefer to use wood and not metal or plastic to create the cockpit shell. Why do I suggest learning at least the rudiments of the art of woodworking instead of using a more modern approach like fabricating all the parts with a 3D printer; after all, all the parts actually go through the stage of being 3D CAD drawings?
The answer is simple – cost, time and flexibility.
Just as an exercise I investigated the costs of building a life-sized Flight Simulator Cockpit shell using a 3D printer.
The result? The time taken to cut and rout a simple wood part was far shorter than to “print” it and vastly cheaper – absolutely no contest.
Then comes the problem of a curved surface… When building a one-off structure with hobbyist tools, the easiest approach to approximating the curved shape of an aircraft’s fuselage is to make the surface out of many small flat panels (2D surfaces with thickness) and when the whole unit is assembled, the rough surface edges of each panel is sanded down to a plausible approximation of a curve. How do you sand plastic into a smooth curved surface?
And then of course, there is the flexibility… a small change or afterthought or addition is easily and cheaply constructed in the home woodworkshop. A broken part is also easily repaired when it is made out of wood.
What kind of wood?
A full size cockpit uses a surprising amount of wood, so cost is a major factor. We also need to remember that a life-sized cockpit will easily fill a domestic room. This means that in its lifetime it will probably have to be re-located. (Life just works that way!) So we can’t just glue the parts together, they have to be fastened with screws and wood-joints.
There is also the matter of expansion. Solid wood pieces have a horrible habit of expanding and contracting depending on the humidity. In cockpit building there are two ways to counter this:
The first way is to use many small pieces instead of large solid wood pieces. Ideally, if the part can fit onto an A4-size sheet of paper, it’s good. Of course, there are many pieces which have to be longer, but we do what we can. On larger such pieces, try to use plywood unless the part needs the strength of solid wood. When using solid wood, soft woods like pine are easiest to work with.
The second way is “Dave’s secret trick” …
Use wood flooring panels…
They usually come in strips of 1500mm to 2000mm in length/ 200 mm in width/ with a thickness of 14mm or 15 mm. Because of its construction, these panels expand and distort far less than solid wood pieces; and large panels can easily be made by glue-ing strips together using the specially designed tongue-and-groove interlocking system. Different manufacturers have different interlocking systems, but the all produce a remarkably inconspicuous joint along the grain of the high-quality side.
And guess what? These floor panels work out much cheaper than solid wood per square running metre.
Caveat: They have one problem though, they are not very strong longitudinally and therefore are not for structural supports, but are are ideal for the cockpit surface panels (which are later sanded and painted).