The Challenges of Machining Stainless Steel
Stainless steel is one of the most commonly requested engineering materials and one of the most demandiing to machine well. Its corrosion resistance, strength and durability make it a favourite across medical, food, mining and industrial applications. The same properties that make it popular are also what make it tricky on the shop floor.
At Element Machining, we are an experienced machine shop with decades of combined machining experience. That experience includes a wide range of steels including stainless, from free‑machining alloys through to tougher austenitic and duplex steels. We work with stainless all the time, so we understand where the real challenges lie and how to manage them effectively.
As our head machinist Brent Airey puts it:
“Stainless steel is a dichotomy. You have to be fast but slow. You have to be gentle but firm. It’s not like mild steels where tool speed doesn’t matter. It has its own personality – you have to respect it.”
Brent Airey – Head Machinist at Element Machining
While stainless steel is one of the most challenging of the common engineering materials, it is still less complex to machine than exotic alloys such as Inconel or titanium. With the right approach, tooling and experience, it delivers excellent results.
Stainless Steel machining’s biggest difficulties: heat generation and work hardening
One of the biggest challenges when machining stainless steel is heat.
Stainless alloys tend to generate heat rapidly at the cutting edge. The heat builds up in the tool, which then transfers that energy directly into the workpiece. This can cause localised tempering and, in some grades, rapid work hardening of the material surface. Once stainless steel work hardens, the cutting tool is no longer cutting soft material. It is now pushing into a hardened skin that resists penetration, accelerates tool wear and increases cutting forces. This causes more heat, more hardening and now there’s a runaway heat problem.
“Stainless is special: get to know it, like a lover – treat it right. You’ve got to keep your tool moving otherwise it will overheat. You can’t let it get too hot. If you leave your tool in one spot too long, she’ll get a temper which can ruin a job.”
Brent Airey – Head Machinist
Managing this requires the right balance of tooling geometry, coolant delivery and consistent cutting engagement. Clean entry, stable depth of cut and avoiding unnecessary dwell all play a critical role in keeping heat under control.
Tool speed and the polishing effect
Another common issue when machining stainless steel is incorrect surface speed.
If the tool speed is too high or the feed is too light, the tool can polish the surface rather than cut it. Polishing smooths and compresses the material surface, making it even harder for the tool to bite in on the next pass. This effect compounds quickly and leads to poor surface finish, dimensional drift and premature tool failure.
Machining tools aren’t cheap and any machine shop that is going through too many tools is driving up the cost per piece. It’s better to pay for an experienced machinist with low tool spend than a cheap machinist who costs more because of premature tool failure costs.
Stainless steel rewards decisive cutting. The tool needs to stay engaged and remove material cleanly rather than skating across the surface.
“Like I said, you’ve got to treat stainless right. If you rub it too much the shine can stop your tool from penetrating. You’ve got to keep moving – not too fast, not too slow.”
Brent Airey – Head Machinist
Selecting the correct cutting parameters and maintaining them consistently is key. Proper tool engagement avoids polishing, reduces work hardening and produces a more stable, repeatable machining process.
Experience makes the difference
Machining stainless steel successfully is not about one single trick. It is the combination of heat management, tooling selection, machine rigidity and process discipline. Understanding how the material behaves under the cutter only comes with experience.
“I learned about machining stainless on manual tools. I got to know the feel of the right amount of pressure, the sound it makes when you’re doing a good job. With CNC, you lose that physical sensation. These days I’m listening to the sound – the whine of the machine when everything is working just right.”
Brent Airey – Head Machinist
At Element, our team, led by Brent, has decades of combined hands‑on experience machining stainless steel components across a wide range of industries. That experience allows us to anticipate issues before they appear and apply proven strategies to keep jobs running smoothly.
Stainless steel may be demanding, but in capable hands it is a reliable and highly versatile material.
Need stainless steel parts machined?
If you have a stainless steel project coming up and want it machined correctly the first time, we can help. Our team is happy to review your design, discuss material choices and provide a clear, competitive quote.
Element Machining is available to make parts in our Perth workshop for local projects and we can express ship anywhere in Australia or the world.