Plasma Cutting Stainless Steel: 10 FAQ Answered By Experts

Absolutely. Plasma is one of the most effective methods to cut stainless steel over a wide range of thicknesses. However, the type of stainless steel cutting table and plasma source you use makes a big difference.

Does the cutting machine make a difference?

The build quality of your cutting machine will make a significant difference in the cut quality in the long run.

Specifically, the edge quality (ripples vs no ripples) and angularity of the cut may be impacted by mechanical imperfections of the cutting table.

You need to assess the stiffness of the gantry (Y-axis that moves over the material to be cut) and whether the construction of the rails can be affected by the heat dissipated by the cut.

Whilst cut quality may look the same when machines are brand new, heat can bow the metal construction of your table over time, which may impact the straightness of the cutting machine.

Next to this, various machine components, like the drives, rails, and gears impact motion. Poorly assembled or poor quality components could lead to motion irregularities.

This, in turn, causes vibrations, which transfer through the machine axis into the cut edge and can cause a rough-cut surface, nonlinear cut edges, and overall poor cut quality.

Therefore, we recommend checking the quality of the drives, rails, and gears before you purchase any plasma cutting machine.

Does the plasma system make a difference?

The main difference between a low-cost air plasma system vs an industrial type of plasma cutting systems relate to the types of gasses that are used to cut and the pressure at which the plasma gas will come out of the torch. Both of these significantly impact the end-result of the cut.

The image below illustrates the quality difference one can expect between using a more expensive F5 blend gas as plasma cutting gas vs. a cheaper solution like compressed air.

Stainless bars boast a range of highly valued characteristics, but by far the most important of these is the one that gives the alloy its ‘stainless’ name: corrosion resistance. This is achieved through the alloying process - stainless steel is a metal alloy whose chief constituents are iron and chromium, and to qualify as stainless steel, the metal must contain no less than 10.5% chromium (in practice it’s often slightly more).

Other common ingredients generally present at varying percentages in stainless steel include silicon, carbon and manganese. Further alloying additions for achieving specific applications/characteristics of the finished product are often introduced during manufacture; these might typically include titanium, molybdenum, nickel, copper or nitrogen. The total quantity of alloying ingredients in a finished piece of stainless steel can frequently be as high as 30%.

We’ll talk more about different types of stainless alloys and their respective qualities a little further on in this guide, but when looking to buy stainless steel online - be it bars, rods, or stainless steel tubes, sheets and angles - you should always be aware that the metal is manufactured and graded in many different ways.

This is done in order to meet varying standards of corrosion resistance for use in very specific types of applications and environments, and it’s why you’ll find so many different ‘grades’ of stainless products listed on the catalogue pages of most stainless steel bar suppliers.