Pin or Tail? Identifying Dovetails

Call me slow but it took a long time for me to figure out the difference between a “pin” and a “tail” when looking at half blind dovetails.  When I look at the outside corner of a drawer, the pins and tails look identical in shape, so which is which?  After years of study, I now understand the difference and I want to share my knowledge with my website visitors.  I use a Porter-Cable 4216 Dovetail Jig and the drawer fronts and backs (pin boards) are always positioned in the top clamp horizontally.  The drawer sides (tail boards) are always positioned in the side clamp vertically which means that the tails are cut completely through the board (duh!).  Other ways to identify the pins from the tails are shown below.

pin-or-tail

Looking at the corner of a drawer, the shape of the pins and tails are identical so which is which?

Pin - Tail Identification

Looking at the dovetail cuts from the inside surface reveals the difference between the pins and tails. The pin cuts are blind and have parallel sides. The tail cuts go through the board and have the dovetail shape.