Choosing the Right Grinding Wheel for Metal Fabrication Work
Grit size, bond type and wheel speed considerations for cutting and finishing applications.
Grinding wheels are not interchangeable. The abrasive, grit size, bond and shape all affect how fast the wheel cuts, how long it lasts and how safe it is on the job. Here is how to match the wheel to the work.
The material you are grinding
Aluminium oxide wheels are the general choice for steel and ferrous metals. Silicon carbide suits non-ferrous metals, cast iron and non-metals such as stone. For stainless steel, use a wheel made for stainless, often labelled as iron-free, so it does not contaminate the surface.
Grit size
A coarse grit (low number) removes material fast but leaves a rough surface. A fine grit (high number) gives a finer finish with slower cutting. Typical choices are coarse for heavy stock removal and weld dressing, and finer for finishing and sharpening.
Wheel type and application
- Cutting-off wheels: thin, for cutting bar, tube and sheet. Never use them for side grinding.
- Grinding wheels (depressed centre): for weld removal and heavy stock removal with an angle grinder.
- Flap discs: grind and blend in one step; good for finishing welds.
- Bench and cylindrical wheels: for tool sharpening and precision grinding on the right machine.
Match the wheel to the machine
Check that the wheel's maximum operating speed (RPM or m/s, printed on the wheel) is at or above the machine speed. Match the wheel diameter and bore to the grinder, and use the guard supplied with it.
Safety
Inspect a wheel for cracks before use, ring-test bench wheels as the maker advises, store wheels dry and flat, and wear eye and face protection. Do not use a wheel past its expiry date.
Key Takeaways
- Pick the abrasive by the material being ground.
- Check that the wheel's speed rating is not lower than the machine speed.
- Use cutting wheels for cutting and grinding wheels for grinding.
This article is general guidance. For a recommendation for your own application, contact our engineering team. Abrasives and grinding wheels →