Buying guide
Abrasives for stainless steel (INOX): cutting, grinding and finishing
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Stainless steel stays corrosion-resistant only as long as its surface stays clean. The wrong disc can leave iron particles on the workpiece or overheat the area, and a few days later the result shows up as rust spots or discolouration.
This guide explains why stainless needs dedicated abrasives, what Tyrolit states about disc purity and how to work correctly from cutting to finishing.
Key takeaways
- Stainless is easily contaminated by carbon steel particles: use dedicated or 2in1 discs and never go back to stainless with a disc that has been used on carbon steel.
- Tyrolit describes its stainless cutting discs by their chemical purity, without a numeric threshold; the figure of at most 0.1% Fe, S, Cl appears only for zirconia (ZA) flap discs, in an older English-language Tyrolit catalogue.
- Thin cutting discs and moderate pressure limit heat input and heat tint.
- Typical workflow: cut with an INOX or 2in1 disc, then use a flap disc in grit 40/60 for stock removal and 80/120 for finishing.
Why stainless steel needs dedicated abrasives
The corrosion resistance of stainless steel comes from a very thin passive layer that forms on its surface. Iron particles left on the workpiece rust and can start corrosion at that very spot. That is how rust spots appear on railings, tanks or food-processing equipment shortly after installation.
The second issue is heat. Local overheating causes heat tint, a yellow, blue or brown discolouration, and the tinted zone is generally less resistant to corrosion. Typical sources of contamination are:
- cutting or flap discs previously used on carbon steel;
- wire brushes, files and other tools shared with carbon steel;
- sparks and dust from carbon steel work nearby;
- abrasives not declared suitable for stainless.
Fe, S, Cl purity: what Tyrolit actually states
Abrasives for stainless are often described as free of iron, sulphur and chlorine. It pays to know exactly what the manufacturer states for each type of disc:
- INOX cutting discs and the Premium and Basic 2in1 discs: Tyrolit describes them by their chemical purity, which prevents corrosion, rust spots and loss of fatigue strength. For cutting discs, the documentation gives no percentage threshold.
- Zirconia (ZA) flap discs: an older English-language Tyrolit flap disc catalogue states an iron, sulphur and chlorine content of at most 0.1% and recommends them for stainless steel. The 2026 catalogue describes the Premium 2in1 flap discs by their chemical purity, without a figure.
- The 2026 Tyrolit catalogue includes a "Free of Fe, S, Cl" symbol in its pictogram legend, and Tyrolit cutting discs for stainless carry the red INOX label.
Declared specification vs discs without standard markings
With a disc that has no standard markings and no identifiable manufacturer, you cannot know its grain and bond type, nor whether it suits stainless or may bring iron, sulphur or chlorine onto the surface. Tyrolit discs are manufactured to the European standards EN 12413 (bonded discs) and EN 13743 (flap discs) and carry a declared specification (grain, grit and, on bonded discs, hardness and bond) and full markings: maximum speed, safety pictograms and, on cutting discs, the expiry date. On a stainless job, the wrong disc can ruin the whole workpiece.
See also: Cheap vs premium discs
Cutting stainless steel: which disc and which thickness
For cutting, choose a disc marked INOX, with a red label, or a 2in1 disc for steel and stainless, with a blue label. Tyrolit offers INOX discs in the Premium, Standard and Basic lines and discs for steel and stainless in the Cerabond X, Premium, Standard, Basic and ONE lines. The Premium INOX disc is designed specifically for corrosion- and acid-resistant steels.
Thickness directly affects the heat that goes into the workpiece; for its Premium and Standard INOX discs, Tyrolit cites minimal heat generation in the workpiece. The manufacturer recommends:
- 0.75–1.9 mm for Premium INOX and 1.0–1.9 mm for the other lines: fast cutting and minimal burr, for sheet, tubes and thin profiles.
- 2.0–3.0 mm: maximum stability and service life for solid sections; up to 2.5 mm for Standard INOX.
- Basic INOX at 1.0 mm: precise, fast cutting for everyday jobs.
Let the disc do the cutting
Do not press hard or force the disc into the cut. High pressure raises the temperature, increases heat tint and wears the disc faster. A steady feed gives the best result on stainless.
See also: Choosing a cutting disc
Workflow: cutting, grinding, finishing
After cutting or welding, the surface is worked in stages, from coarse to fine grit. For stainless, Tyrolit recommends zirconia (ZA) flap discs and also offers ceramic flap discs dedicated to stainless; grits 40/60 are for fast stock removal and 80/120 for fine grinding.
For large weld seams on thick parts, the first step can be done with a grinding disc for stainless, with the flap disc then taking over the smoothing. Work with an oscillating movement and vary the angle slightly so that heat does not build up in one spot; regular breaks prevent the grinder from overheating.
| Step | Disc | Grit or thickness | Purpose |
|---|---|---|---|
| 1. Cutting | INOX or 2in1 cutting disc | 0.75–1.9 mm for sheet and tubes; 2.0–3.0 mm for solid sections | Fast cut, minimal burr, low heat |
| 2. Weld seam removal | ZA or ceramic flap disc for stainless | 40 or 60 | Fast stock removal |
| 3. Smoothing | ZA or ceramic flap disc | 80 | Removing the scratches from the previous step |
| 4. Finishing | ZA flap disc | 120 | Fine, even surface |
Cool grinding without discolouration
The Tyrolit Premium CERAMIC flap disc for stainless and the Premium FASTCUT flap disc have an additional layer of additives for cool grinding which, according to the manufacturer, prevents discolouration of the workpiece and reduces rework.
See also: Flap disc grit guide
Keep stainless tools apart from carbon steel tools
A common workshop mistake is using the same disc on both materials. A disc that has cut or ground carbon steel can transfer iron particles to stainless, even if it is a 2in1 disc. The rule is simple: a disc used on carbon steel never goes back to stainless.
- Store stainless discs separately and label them clearly.
- Use brushes, files and clamping fixtures dedicated to stainless.
- Do not work carbon steel next to finished stainless parts.
- Where the job specification requires it, for example in food processing, apply the surface treatments set out in the documentation.
Protection when grinding stainless
Grinding dust must not be inhaled. Tyrolit requires a suitable extraction system for all dry cutting and grinding; wear safety glasses, a suitable respirator (FFP2 or FFP3), hearing protection and gloves. Also wear gloves when fitting flap discs with a fibreglass backing, and never grind with the periphery of a flap disc.
Frequently asked questions
Can I use a steel cutting disc on stainless?
It is not recommended. A disc for carbon steel is not formulated for stainless and, especially if it has already been used, it can leave iron particles on the surface. Choose an INOX or 2in1 disc and use it on stainless only.
What is the difference between an INOX disc and a 2in1 disc?
A 2in1 disc is designed for both steel and stainless steel, so it is practical in a workshop that handles both materials. An INOX disc is dedicated to stainless steel; the Premium INOX line includes the thinnest Tyrolit cutting discs for angle grinders, at 0.75 mm.
What does "free of Fe, S, Cl" mean on an abrasive for stainless?
It is how the manufacturer indicates an abrasive free of iron, sulphur and chlorine, elements you do not want on a stainless surface. An older Tyrolit catalogue gives at most 0.1% for zirconia flap discs; for cutting discs, the 2026 catalogue describes chemical purity without a numeric threshold.
Which flap disc grit should I use for stainless steel welds?
Use grit 40 or 60 to remove the weld seam, then 80 for smoothing and 120 for finishing. Do not skip steps: deep scratches left by a coarse grit are hard to remove directly with a fine one.
Why do rust spots appear on stainless steel after grinding?
Typical causes are carbon steel particles transferred from discs, brushes or shared tools, and overheating of the surface. Use abrasives dedicated to stainless, keep tools separate and work without excessive pressure.
Tyrolit abrasives for stainless steel
Galflex is an authorized Tyrolit distributor in Romania. Browse the Tyrolit cutting discs and flap discs for stainless steel or contact us for a recommendation tailored to your job.
See the Tyrolit cutting and flap disc range · Contact us for an offer
Sources and documentation
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