Will Plasma Cutters Cut Stainless Steel?

Yes, plasma cutters can effectively cut stainless steel, as well as other conductive metals such as aluminum, copper, and brass. Plasma cutting offers clean, precise cuts, high-speed operation, and minimal heat-affected zones, making it a popular choice for cutting stainless steel in various thicknesses.

Here, I’ll tell you everything you need to know about using plasma cutters to cut stainless steel.

Can a Plasma Cutter Cut Stainless Steel?

Yes, a plasma cutter can cut stainless steel perfectly well.

Plasma cutting is versatile because it allows you to tweak the cutting settings closely according to the final result you want. You can choose from a wide variety of gasses for cutting, and some plasma cutters can even cut stainless steel up to 160mm thick.

Despite that, plasma cutting is on the cheaper side of the scale with it comes to cutting stainless steel. It’ll cost you less than laser cutting, for example.

How to Cut Stainless Steel With a Plasma Cutter

Cutting stainless steel with a plasma cutter involves making sure you have the right equipment, tweaking the settings, and choosing the right gas.

Here’s how to do all that.

Choose a Reliable Cutting System

The choice of your plasma cutting system mainly depends on your budget, but you also need to take the final result you want into consideration.

For example, cheaper air plasma systems will have limited cutting options. You’ll likely only be able to cut thinner plates–no more than 30mm thick. Also, air cutters will give you a dark finish because they only use air to cut. The nitrogen in the air will cause a black finish, and the oxygen will cause a choppy finish around the edges.

Most users will be okay with these downsides because air cutters are much cheaper, but if you want the best result, consider industrial CNC plasma cutters. 

Industrial cutters allow you to choose from various gasses, depending on the result you want (more on that below).

They also have a smooth, shiny finish and can cut much thicker stainless steel plates.

Select the Right Consumables

Before attempting to cut stainless steel with a plasma cutter, make sure you have the right consumables. It’d be better to check with your supplier first to know which ones you’ll need—because stainless steel often needs different consumables from other materials.

Selecting the right consumables doesn’t only ensure you get a smooth result, but also helps reduce dross, which can be a pain to clean because of its hardened state.

Choose the Right Gas

Choosing the right gas for cutting depends on whether you’re going for single-gas or dual-gas cutting.

Here are the common options for single-gas cutting:

• Oxygen: Oxygen isn’t the best option for cutting stainless steel because it ends up causing burnt edges and a choppy finish. However, it’s one of the cost-efficient options.
• Nitrogen: Nitrogen is a common choice for cutting stainless steel because it cuts at high speeds.
• Compressed air: Compressed air causes a black finish around the edges because of the high nitrogen content, so it’s not the best option, but it’s low-cost.

Dual-gas systems are highly versatile and are often the choice of professional cutters. Here’s an overview of the common options for cutting stainless steel:

• Hydrogen/Argon-Nitrogen: H35 and nitrogen are often selected for cutting stainless steel because they result in a square cut edge. However, they may result in more dross than other options.
• Nitrogen-Water: the nitrogen and water pairing is a cost-efficient one, although you’ll need a water table for it. It provides a smooth top edge.
• Hydrogen/Nitrogen-Nitrogen: this pairing’s use is limited because you can only use it to cut stainless steel plates less than ⅜ inches thick. However, it provides excellent angularity.

Adjust Advanced Controls

Some advanced piercing controls can make your life much easier when cutting stainless steel.

For example, some plasma cutters have a two-step pierce height control feature. When you enable this feature, the piercing starts at ¼ an inch before the torch retracts to its final height. That way, the torch returns to the final height until the piercing is done, which protects the nozzle from damage.

You won’t believe how fast these nozzles get damaged—unfortunately, I’m well familiar with the drill—, so if your cutter has this feature, it’d be wise to make use of it.

Some plasma cutters also have a diverter control feature, which blows the molten metal pieces away from the piercing area, thereby protecting the shield cap from damage.

Tips for Cutting Stainless Steel With a Plasma Cutter

If it’s your first time using a plasma cutter with stainless steel, you may need some tips to guide you. Here are some tips that may make your first time easier than mine!

When cutting painted stainless steel, make sure you have a solid ground connection as close to your cutting area as possible. The same goes if you’re cutting a particularly dirty stainless steel plate.

Opt for a slower cutting speed if you want a dross-free cutting process. Higher speeds are generally time-efficient, but they result in plenty of dross, which may be a pain to clean after you’re done. If you have no option but to use a high speed, keep it constant for the whole cutting process and ensure the stable working table.

Make sure to work in a safe area with appropriate filtration and fume extraction systems. Cutting stainless steel produces risky fumes that may lead to respiratory diseases if consumed in large amounts. Its fumes contain a lot of chromium, a toxic element known for causing cancer.

Final Thoughts

Plasma cutters are actually an excellent option for cutting stainless steel because they’re not as expensive as water jets or laser. Besides, they’re highly versatile and allow you to tweak the cutting settings accurately.

The gas you choose for cutting also plays a big role in how your cutting will look like. Most industrial cutters have dual-gas systems because they allow for better accuracy and smoother finishes.