Over the years, I've managed to accumulate quite an assortment of nuts, bolts, and fasteners of all sizes. Unfortunately, they all seem to wind up in one big jar, making it almost impossible to find the size that I need. So I finally decided to sort them out.

To identify all the different sizes, I made this convenient thread gauge. It's just a block of wood with various sizes of bolts. The bolts range in size from #4-40 to 1/2"-13. I marked the thread size right next to each bolt. And in front of each bolt, I drilled a hole that matches the diameter of the fastener.

I also cut a couple of pieces from a yardstick and screwed them to the sides of the gauge. A small magnet on the end of the jig holds loose nuts, washers, etc. And an eye bolt on the end allows me to hang the gauge up on the wall. Now when I run across a lone bolt, machine screw, or nut, I no longer have to try and guess the length or thread size.