This is a remix of This thing. His caliper system didn't work on the widely used Westcott Stainless Steel Rulers with that non-slip cork base I see everywhere (Like here). I modified it to fit that ruler. Just print this out and fit them. The only problem is that the top is unstable, however the cork on my ruler (don't know about others) starts at the 0 mark, so that was pretty good. I just used glue to fix the caliper to the top and the ruler works like a charm. It's a bit hard to get the ruler into the bottom part of the caliper, since my printer doesn't do lips very well, but that makes it more stable. It's harder to slide because of the cork, but I like it like that. I print the top portion upright instead of flat against the bed. This ensures that the edge is completely flat, and also the opening is the right size with no drooping from the bridging of the plastic. There was some slight curling on the top portion around where the inside measurement edge is, but nothing a bit of sanding didn't fix. I wiped it with acetone to give it a smooth finish. The bottom portion I printed flat because I figured that was the best way. I can't think of any other way to do it. This was printed on the Replicator 2.