[Viator]

Well, I found cutting U-shape in such a small scale too difficult (options A & B, phase 1). The result was less than acceptable. Much easier is to make the L-shapes (option D, phase 1). Of course one can cut only the straight rectangles (option C phase 1 - which is, again, much easier than to cut L-shapes), however the U-shape glued of three separate rectangles (option C, phase 2) is too weak (the area of a single gluing tab doesn't exceed 1/2 mm2). The option D is a good compromise.

The image #3 shows the comparison of the old U-frame and the new L-shapes, much more slender, neat and still rigid enough to be loaded with the "wires" later.