Anyone who’s tried it knows that “pipe” or “tube welding” is an art that takes a while to master. This outstanding phototutorial by Amy Qian won’t substitute for the hours of practice needed to draw a good bead around a fishmouth seam, but if you’ve got the chops and are looking at making a bike frame, she’s done a great job of documenting her own process. The wheels she’s used are Harbor Freight cheapies with refit bearings! [via adafruit]