The old bed of the Mazda B2500 (1996) pickup truck has rusted, so I decided to build a new flatbed tray from scratch. I ordered some metal tubing and started cutting and welding pieces together. I decided to make a flatbed with sides. I used 40x40x3mm tubing for two main beams, and the rest of the material is 40x40x2mm, 30x30x2mm, and 60x30x2mm tubes.