I’m designing a battery box for The Bride, using both permutations of “CAD” — cardboard and computer. First, I figured out what I needed with some old scraps of illustration board.
Once I had something that worked, I measured the dimensions. After I transferred that into the computer, I printed off a full-scale template on stiff paper to ensure that I hadn’t screwed up the dimensions. The sloping shape will allow the box to snake into position within the frame tubes with the engine and swingarm in place.
And finally, I added a bunch of drill holes along the crease lines and at the intersections of cuts.
I discovered this trick while making the battery box for the CL125S. Drilling out the hole locations first, before any cutting or bending, ensures that I lay out the dimensions accurately — just connect the dots. Then, once it’s in the bending brake, the reduced mass along the bend line encourages the metal to fold in line with the holes. The blue line is where I’ll add a rolled stiffening crease with my die roller. (Die rolling straight across a piece, edge-to-edge, keeps away the “oil can” distortion pixies.)
I’ll pick up an 18 gauge sheet of mild steel and see how it goes.