A bench grinder is a simple tool — a motor spinning two abrasive wheels — but it handles a surprising range of tasks. Sharpening chisels and plane irons, deburring metal, shaping custom hardware, cleaning rust, polishing, and maintaining garden tools all happen on the grinder. At $50 to $120 for a quality 6 or 8-inch model, it is one of the most versatile bench tools in the shop for the price.

Bench Grinder Uses

Choosing a Bench Grinder

6-inch vs 8-inch: The wheel diameter determines the grinding surface area and the surface speed. An 8-inch grinder provides a flatter grinding surface (less curvature across the wheel face) and more material between the arbor and the workpiece. For a home workshop, 6-inch handles most tasks. If you sharpen wide tools (plane irons, jointer knives) or do regular metalwork, the 8-inch justifies the extra $30 to $50.

Speed: Standard bench grinders run at 3,450 RPM. Slow-speed grinders (1,725 RPM) generate less heat, which is critical for sharpening heat-sensitive tool steel. The Rikon 80-805 ($100) and WEN 4286 ($70) are popular slow-speed 8-inch models. The slow-speed grinder is the better choice for a woodworking shop where edge tool sharpening is the primary use.

Upgrade the wheels. The gray wheels included with most grinders are coarse (36 or 60-grit) and friable — they break down unevenly and are poor for precision sharpening. Replace them with white aluminum oxide wheels (Norton 3X, $15 to $25 each) in 60-grit and 120-grit. White wheels run cooler, cut cleaner, and are the standard for tool sharpening.

Primary Use: Tool Sharpening

Chisels and Plane Irons

The bench grinder establishes the primary bevel (25 degrees for bench plane irons, 25 to 30 degrees for chisels). Use the tool rest adjusted to the correct angle, or a dedicated sharpening jig (Wolverine system, $100) that holds the tool at a precise, repeatable angle.

Grind on the white wheel using light passes. Dip the tool in water every 3 to 5 seconds to prevent overheating — if the edge turns blue, the steel has lost its hardness and must be ground past the damaged zone. See our plane blade restoration guide for the complete sharpening process.

Drill Bits

A drill bit sharpening jig attached to the grinder holds twist bits at the correct angle. Freehand sharpening on the grinder is possible but requires practice. The bench grinder is faster than a dedicated drill bit sharpener for quick touch-ups.

Garden and Lawn Tools

Lawn mower blades, hatchets, axes, machetes, shovels, and hoes all sharpen on the bench grinder. Clamp the tool securely or use a sturdy grip. Follow the existing bevel angle and take light passes.

Lawn mower blades in particular benefit from regular grinder touch-ups. A sharp mower blade cuts grass cleanly (promoting lawn health) instead of tearing it (which causes brown tips and disease).

Deburring and Metal Cleanup

After cutting metal with a hacksaw, reciprocating saw, or angle grinder, the cut edge has sharp burrs and rough spots. A quick pass across the bench grinder wheel removes the burrs and produces a clean, safe edge.

Round the corners of cut metal brackets, smooth weld beads (rough cleanup before filing), and reshape hardware that does not quite fit. The grinder removes material from mild steel efficiently — much faster than hand filing for bulk removal.

Wire Wheel Operations

Replace one grinding wheel with a wire wheel for cleaning and surface preparation:

Remove rust from tools, hardware, and metal parts
Strip paint from metal surfaces
Clean threads on bolts and fasteners
Deglaze metal surfaces before painting or welding
Polish rough cast-iron surfaces

Safety critical: Wire wheels throw broken wire fragments at high velocity. Wear safety glasses AND a face shield. No exceptions. Wire fragments embed in skin and eyes. Stand to the side of the wheel, not directly in front. Never wear loose clothing or gloves that can catch in the rotating wheel.

Buffing and Polishing

Replace a grinding wheel with a cloth buffing wheel and apply buffing compound for metal polishing:

Polish brass hardware to a mirror finish
Buff hand tool surfaces after rust removal
Polish knife blades and edge tools after sharpening (final stage)
Restore chrome-plated fixtures

Use different buffing compounds for different metals: green rouge (chromium oxide) for steel, white rouge for stainless, red rouge for brass and copper. Apply the compound to the spinning wheel, then press the workpiece lightly against the charged wheel.

Custom Metalwork

The bench grinder shapes and forms small metal parts:

Grind custom tool bits from high-speed steel blanks
Shape screwdriver tips that have been damaged
Create custom hooks, brackets, and holders from steel rod
Bevel and chamfer metal edges for welding preparation
Reshape bent or damaged hand tool components

Setup and Safety

Mounting

Bolt the grinder to a solid surface — the workbench, a dedicated grinder stand, or a heavy shelf. The grinder vibrates during use, and an unmounted grinder walks across the bench. Use bolts through the mounting holes, not just the rubber feet.

Tool Rest Adjustment

Position the tool rest as close to the wheel as possible without touching — 1/16 inch gap maximum. A large gap between the rest and the wheel allows workpieces to catch between them and kick violently. Adjust the rest before each use.

Eye Shields

Most bench grinders include plastic eye shields above the wheels. Use them. Adjust them to cover the gap between your face and the wheel. They supplement (not replace) your safety glasses.

Wheel Dressing

Grinding wheels load up with metal particles and develop grooves from uneven wear. A wheel dresser ($8 to $15) — a star-wheel or diamond-point tool — trues the wheel face and exposes fresh abrasive. Dress the wheel before sharpening for a flat, clean grinding surface. A dressed wheel cuts cooler and removes material more evenly.

Wheel Inspection

Before each use, visually inspect the wheels for cracks. A cracked grinding wheel can explode at operating speed — the fragments are lethal projectiles. If you see a crack, hear a dull thud when tapping the wheel (a good wheel rings), or notice excessive vibration, replace the wheel immediately.

Bottom Line

A bench grinder with white aluminum oxide wheels and a wire wheel handles tool sharpening, metalwork, cleaning, and polishing for $70 to $120. Replace the factory gray wheels, mount the grinder securely, adjust the tool rest close, and always wear a face shield with wire wheel operations. It is one of those tools that sits quietly in the corner until you need it — and then you need it constantly.