A Hidden Detail of Wooden Bench Planes

I've written before about details of wooden planes, details that aren't apparent until you study them.  Here's another one that I recently stumbled upon.  Maybe I hadn't noticed it before because until recently I didn't have any old wooden bench planes - I only had the ones I've built.

Smoothing plane built last year

Jack plane built in early 2019

When making the wedges of these planes, to form the back end (where you tap with a hammer to tighten) I square a knife line all around, then cut off the excess and plane the end grain smooth before angling the sides and smoothing the edges.

Back end squared to the front surface (and back surface) of the wedge

But I noticed that in the old woodies that I recently got at an auction that the back end of the wedges is angled forward.

Greenfield Tool Co. jack plane

Close-up of the wedge shows the back end angled forward

Auburn Tool Co. jack plane

Close-up showing top of wedge angled forward

Then there's the J. Pearce smoother that I got in that same auction.

Not as easy to tell, but this wedge is also angled forward at the top

And finally, my only other woodie that's like a bench plane: an old A. C. Bartlett's Ohio Planes toothing plane.

This plane clearly has the back of the wedge similarly angled.

In all cases, the angle was between 8° and 12°.  One can guess the function of this little detail: to enable easier access with a hammer and avoid hitting the iron at the same time.

Just another little nugget about wooden planes.  The old plane makers really knew what they were doing.