I'm studying David Charlesworth's new The Through Dovetail DVD, and I've noticed a small precision square he uses to check squareness of tails with the face. Here are some unauthorized screen shots for reference (sorry, David):
DLC dovetail square.jpg DLC square 2.jpg
Anyone have experience with this tool? Where can I get one?
Sterling Toolworks makes something similar, and maybe its rule's tiny end is even smaller than the one above, but I think the overall tool might be larger in the hand:
Sterling dovetail square.jpg
In the meantime, I've made a little one out of cherry that might end up serving me well enough, but I want to look at all the possible sources because I only want to do this once.
Thanks for the help.