I taught some guys how to
make mortise and tenon joints and snapped these photos of the
mortise and tenon gauge.
I made it back in 1986 out of a piece scrap brass. It saves lots
of time and there is no trial and error testing of the tenon or
mortise before you put them together.
It looks like a tuning fork and actually rings like one.
The principle of this tool is that it is a go-no-go gauge.
Anything that the fork will fit over will fit in a hole that the
other end will freely move in. This one is for a 1/4th-inch
joint. If you make one of these, size the slot and probe to the
chisel you always use to cut the mortise.
I don't use a depth stop on the probe end of my brass gauge
anymore. Instead I use a 19th-Century English joiner's depth
gauge for measuring the depths of mortises as well as bored
The wood is mahogany and the steel probe is 6 3/4ths inches
long. I plan on making a bigger version of this tool for bowl
James E. Price