I already have a guarge heater 16amps on a 220 American 120/240 2 pole 20amp braker. I bought a table saw 13amps. I would like to just continue the wire to my saw. Can I run them both with a 40 amp braker?

To use a 40 amp breaker , the entire circuit wiring needs to be a min of #8 wire.

Or use the #12 circuit and only one unit at a time.