Grant Erwin wrote:

How do you calculate how much your shielding gas is costing you per minute? If I
have an M sized tank of C25 (capacity 125) and I'm running it 20 cubic feet per
minute at 20 psi, how many minutes will that flow?

Is there a primer somewhere online or in a book that breaks this down?

Grant Erwin

Connect a running time meter to the gas on contactor relay of your mig
welder and read it when the bottle runs dry. Divide the cost of the
gas cylinder by the number of minutes recorded on the timer.

John