Angle Grinder Buying Guide: 100mm, 125mm or 230mm?

Angle Grinder Buying Guide — a practical guide for Australian trades from the team at Power Tools Direct Australia.

Disc sizes explained, the safety electronics worth paying for, and how Australia’s silica dust rules change the way you cut.

Start with the disc size

Grinder size is defined by the disc it takes, and that single choice determines what the tool can and cannot do.

For most trades a 125 mm grinder is the right first buy. It cuts deep enough for reinforcing bar and light concrete work while staying controllable. Browse the angle grinder range.

The safety features that actually matter

Angle grinders cause more serious injuries on Australian sites than almost any other hand-held tool. Modern safety electronics are not marketing — they are the reason to buy new rather than second-hand.

• Kickback brake — detects a pinched or bound disc and cuts power in milliseconds. This is the single most important feature.
• Electric brake — stops the disc in around two seconds instead of thirty. Prevents the classic ‘put it down while spinning’ injury.
• Restart protection — the tool will not start on its own when power returns or a battery is inserted with the switch on.
• Anti-vibration side handle — reduces hand-arm vibration exposure, which is a genuine long-term health issue.
• Guard that adjusts without tools — because a guard that is annoying to move gets removed.

Never remove the guard. Every experienced tradie knows someone who did.

Cordless or corded?

Cordless brushless grinders now handle most site cutting comfortably. The trade-off is runtime: sustained grinding and heavy concrete cutting will empty a 5.0Ah pack quickly.

For workshop stock removal and long cutting sessions, corded still wins on cost and endurance. For a few cuts on a site with no power, cordless is transformative.

Dust control is now a legal issue

Cutting concrete, brick, tile or engineered stone dry releases respirable crystalline silica. Australian regulators have tightened exposure limits significantly and on-tool dust control is expected on commercial sites.

A dust shroud plus an M-class extractor is the standard solution. Read our guide to silica dust on Australian sites.

Discs: match the disc to the material

• Cutting discs — thin (1–1.6 mm), for cutting only. Never grind with the face of a cutting disc.
• Grinding discs — thick (6 mm), for stock removal.
• Flap discs — abrasive flaps, for blending and finishing steel.
• Diamond blades — for masonry and concrete. See diamond blades explained.
• Wire cups — rust and paint removal. Always wear a face shield; wires break off at speed.

The bottom line

Disc sizes explained, the safety electronics worth paying for, and how Australia’s silica dust rules change the way you cut. Everything we sell is genuine Australian stock with full manufacturer warranty, dispatched same day on orders placed before 1pm AEST from our Sydney warehouse. Standard delivery is $15.99, express is $32.55, and delivery is free on orders over $1,000.

Not sure which option suits your work? Talk to our team — we are tradies too. You can also browse the full power tool range, read the FAQs, or set up a trade account for ongoing pricing.

Frequently asked questions

Is a 100 mm or 125 mm grinder better?

125 mm is more versatile and cuts deeper for a small increase in size and weight. 100 mm suits tight access and lighter one-handed work.

Do I need a kickback brake?

If you cut steel or concrete, strongly yes. It is the feature most likely to prevent a serious injury.

Can I cut tiles with an angle grinder?

Yes, with a diamond blade — ideally wet or with extraction, because tile and stone dust carries silica.

Keep reading

• Silica Dust on Australian Sites
• Diamond Blades and Core Bits for Concrete
• PPE for Power Tools

Related guides