The following is from John Grossbohlin:

Doug,

Caught the measurement item on the blog... I take a little different approach with kids and adults alike when I teach hand cut dovetailing. I show them that you can measure increments without ending up having to find non-scale numbers on the ruler. The attached photo is an example of how to do this. The paper is 2.5" wide and to make three equal sections place the ruler at an angle so that 3 inches are spanned between the edges of the paper. Making marks at the inch marks gets you three equal sections with no "hard" math and without the need to measure in thousandths. I have the kids then measure the increments with the ruler to get an idea of what they "measure" and to show that they are equal (assuming they marked well). On short boards a try square is used to transfer the marks to the ends of the board for dovetail layout. Alternatively, similar marks are made near each end and connected with a straight edge.



As an aside, I taught a class on making hand cut dovetailed pencil boxes one time and right in the beginning of the class I showed that technique. One guy walked away from the bench, sat down, and loudly said, "I'm done." The group was somewhat stunned and one of the other guys asked what was wrong. The response was, "I got my money's worth already with that one trick!" That elicited a lot of laughs... he then rejoined the group around the workbench. ;~)

John