Air or Gas plasma cutter?

[KKamel]

hello

iw been looking into getting a new plasma cutter for my shop, however i would like to use gas to cut not air. The cutter i have been looking at the dealer states that it can only use air to cut not gas. While looking into some other manufacturers most of em have said that new cutters can use both air and gas.

So what is it that makes a cutter only able to use air for cutting and not gas? And if one wants to swap the torch etc to a different brand is it a big thing and what should one watch out for?

[Torchhead]

Why do you want to use gas? It's expensive, it's only marginally better cut quality than clean shop air on steels and it requires a different torch. If you want to use gas for the plasma feed then you need 70 PSI and it needs fairly heavy CFM. You'll empty a tank of gas is short order.

The higher end torches use a separate shielding gas setup (much like MIG) that helps concetrate and get a cleaner cut and to get a REALLY hot flame some torches use pure oxygen as the plasma feed.

The "gas" that you use for the plasma flame has to support the plasma process and most of it is used to blow the vaporized metal through the cut.

A lot of plasma units will take various torches form other vendors BUT you won't get much support from your plasma unit supplier.

So what kind of exotic metal are you trying to cut that would need special cutting gas?