I know that this is probably a question that has come up in the past.

I know most everyone runs Propane for their forge.

Does any one run Natural gas?
What size orifice would be required to push the gas through?

In the Grill and Stove world their are two different sizes, one for LP and one for Nat.

I have a 35 LB requlator, would I need to get different type?

I am preparing to build a burner that use a .035 mig orifice to set up a new forge.