Angle Grinders: Size and Power Guide

Angle grinders are incredibly versatile - cutting, grinding, polishing, cleaning. But getting the right size and power matters. Here's how to choose.

Disc Sizes

115mm (4.5")

The smallest common size. Benefits:

• Lightweight and manoeuvrable
• Good for detail work
• Access to tight spaces
• Lower power consumption

Limitations: Less cutting depth, slower on heavy work.

125mm (5")

The sweet spot for most work. Benefits:

• Good power-to-weight balance
• Decent cutting depth (around 35mm)
• Handles most tasks well
• Wide disc availability

This is what most tradespeople reach for daily.

230mm (9")

The big one. Benefits:

• Maximum cutting depth (around 70mm)
• Faster material removal
• Necessary for concrete cutting

Drawbacks: Heavy, less control, more dangerous if mishandled. Needs respect.

Check our metalworking tools for options.

Power Ratings

Corded

• 700-850W - Light duty, occasional use
• 850-1200W - Good all-round capability
• 1200-1500W - Heavy-duty work
• 2000W+ - Professional/continuous use, larger discs

Cordless

Modern brushless cordless grinders are capable tools. 18V handles most work; the DeWalt 18V range includes excellent options. For sustained heavy use, corded still has advantages.

Features to Consider

Essential

• Adjustable guard - Must be able to position correctly
• Side handle - Can be fitted either side
• Spindle lock - For disc changes

Valuable

• Soft start - Reduces initial torque reaction
• Variable speed - Essential for polishing, useful generally
• Anti-vibration handle - Comfort for extended use
• Brake - Stops disc quickly when released
• Kickback protection - Shuts off if disc binds

Disc Selection

Different discs for different tasks:

• Grinding discs - Thick, for grinding and shaping. Never use edge for cutting.
• Cutting discs - Thin (1-3mm), for cutting only. Never grind with these.
• Flap discs - Layered abrasive, for finishing and blending
• Wire wheels - For rust and paint removal
• Diamond discs - For masonry, tile, concrete

Safety

Angle grinders are dangerous tools. Always:

• Wear safety glasses (full face shield better)
• Use hearing protection
• Wear gloves
• Keep guard in place and properly positioned
• Use correct disc for the task
• Check discs for damage before use
• Secure workpiece
• Be aware of spark direction

Recommendations

For General Trade Work

125mm, 1000W+ corded for workshop; 18V cordless for portability.

For Heavy Metalwork

125mm high-power or 230mm for cutting thick material.

For Occasional DIY

115mm or 125mm, moderate power. No need for expensive features you won't use.

Browse our power tools range.