Hate to be the devils advocate, but you can get a Park TS-2 that will last forever for $175. Building any homemade version is going to have a material cost of $30-$50 plus labor. I really think the frustration of making and using a homemade model is not worth it in the long run. Plus, no need for a dish stick, just flip the wheel around. None of the homemade ones are much different than just using your brake pads as a guide, nor do they work that well if you're doing different size wheels.