I'm curious about how things are made. Today, I'm thinking about the bocal, mostly because I maybe need a shorter one, and am reading up. Seems like a lot of money for a metal tube. And hey, if I have to make my own reeds, why not the bocal, too. There's not a lot of info on how bocals are made: I guess sheets of metal, bent into a tube with a seam, silver soldered together, with the nipple soldered in. Dimensions are controlled by the size and shape of the original sheet, and no doubt also by a mandrel and working the tube after forming. The bend is done with a flexible mandrel (series of bead of defined sizes fixed to a flexible string?) or sand. Here's a video of saxophone making, done in a factory, but which probably bears some similarity.