You could build one. It really cuts the time down on working with tubing. It's just a guide for a hole bit. Really though at the price they sell them for, saves money just buying it if you feel your time is worth something. lol. Makes it a perfect fit every time, with just a simple pull of the drill press lever. I'm all for making tools, but if I can buy it for cheaper than I can make it ( time included), I'm going to just buy it. if you work with tube a lot, the time savings over manual cutting is well worth it. when using a saw, you still need to grind it to the perfect shape after, unless your using a wire saw I guess. This just cuts the angle and a perfect round slip to slide the pieces together. No fuss, but maybe a quick hit with the wire wheel after.