It would seem, what can there be secrets? Many people use on flying models trapezoidal wings — it appears that the process of their manufacture is well established: two templates of the root and end of the profile fixed to the foam blank; two move the cutting filament thermolabile, watching the cutting speed by marking the length of the chords. However, to completely synchronize the movement never fails, which is clearly seen on the “waves” on the surface of the product.
The synchronization problem is solved, it turns out, is extremely simple. It is enough to use a device created by the athlete from Angarsk S. Selivanov, and at the same time to remember that trapezoidal kosol wing — in fact the cone, which should have its own top. The rest will become clear in the figure.