"Tom Lewis" wrote in message
...
Some 40 years ago when I was in high school the shop teacher would stack
regular saw blades together to make dado cuts. Why shouldn't that be
done?

Tom

Accuracy for one. With the combination of blades you can get most any
thickness and easily adjust with shims for a few thousandths if need be. It
is easy to compensate for the undersized plywood.

hey are also made to work together as a set. Blades may vary a bit from one
manufacturer to another so just grabbing blades at random would not give
repeatable results.
Ed