Boomerang in Blender & Sverchok

The idea is to start with two Bezier curves, one for the bottom outline of the boomerang, and one for the top. We will move these in the Z direction to define the thickness of our boomerang, and then create a ruled surface (a "loft") between them.

We pull the curves into the Sverchok node editor using "Scene/Bezier In", and move them in the Z direction by applying a vector as a field. That's the easiest way I found to just move a curve a specified amount. The numbers in the vectors on the left are in meters, so -.0007 means the bottom part of the airfoil is .7 mm thick, and .002 is the top part which is 2 mm thick.

We join the three curves – the original outline, the outline displaced downwards, and the airfoil curve displaced upwards – with a "List Join" node, and create the ruled surface defining the airfoils using the "Surface from Curves" node.

The top and bottom surfaces get filled with n-gons using the UV Connection node. I had to reverse the vertices of one of the surfaces so that the face normal would point in the right direction. Otherwise, that face ended up inside out and the slicer software would complain.

We combine the vertices and polygons, respectively, of our three meshes into lists: one list of all vertices, and one list of all polygons. We can then join these with the "Mesh Join" node into one mesh. That mesh will have duplicate vertices, though. This is taken care of with a "Merge by Distance" node. For this to work cleanly, we need to make sure the "Evaluate Curve" and "Surface from Curves" nodes use the same number of subdivisions; we can make sure of that by feeding a "Number Input" for the number of subdivisions into both of them.

This is the resulting boomerang. The fun thing is that we can still move around the original Bezier curves, and the whole model will update accordingly. Without Sverchok, we would have to convert the Bezier circles into meshes at some point, and then we would lose the ease of modifying.