Nice work, Andy! How's it work? Looks foolproof to me. Laguna should use that and pay you in saw blades!
How's it work?? If you mean does it work well, yes it does. The blade tension lever must be at the limit of its travel or the saw won't start.
If you mean "how" does it work, it interrupts the current to the magnetic coil that keeps the motor switch engaged. This push-button switch has 3 terminals. One is "Common", one is on when the button is pushed, the other is on when the button is released.
“We should be careful to get out of an experience only the wisdom that is in it and stop there lest we be like the cat that sits down on a hot stove lid. She will never sit down on a hot stove lid again and that is well but also she will never sit down on a cold one anymore.” - Mark Twain