Best Bench Grinders of 2022

1. Why invest in a bench grinder?

A bench grinder is one of the most important tools to have in your workshop. Its main purpose is to keep your other tools, especially your saw blades, in perfect working conditions. But this machine can serve many other functions around your workshop or house.

In your workshop, you can use the grinder to smooth welded joints, to grind rivets and even to smooth wood after cutting.

Sharpening goes beyond a mere sharpening of your saw blades. You can use the grinder to repair drill bits, to sharpen cutting tools and even to give a new lease of life to your kitchen knives.

2. Types of bench grinders

Like most workshop tools, bench grinders come in multiple styles and serve multiple purposes. Each type of grinder has its own set of applications, so it’s essential to choose the right tool for your needs.

• Automotive bench grinders: Taking their name from the industry, they are heavy-duty machines equipped with strong wheels engineered to grind hard metals and they usually mount on the workbench via bolts for added stability.
• Woodworking bench grinders: These machines are designed to keep woodworking tools in the best conditions, thus their name. They work at slower speeds than the automotive grinders and are used to sharpen blades and other cutting tools. Most woodworking bench grinders are also designed to be mounted on the worktop.
• Portable bench grinders: Compact electric units designed to be transported from one part to another with ease. They are ideal for professionals who move between worksites and need a reliable tool by their side.

3. Bench grinder sizes

Bench grinder types apart, you can also classify these machines based on their size. There are two popular types, the 6-inch grinders and the 8-inch grinders.

• 6-inch bench grinder: Operates at standard speeds of around 3,000 to 3,600 RPM and deliver sufficient power to handle most tasks with ease. They are perfect for sharpening your knives or multi-purpose blades. These machines are usually used by amateurs and hobbyists.
• 8-inch bench grinders: Built for professional use, these tools have removable blades that can be replaced with wire brushes and other attachments. They withstand heavy-duty demands but work at speeds slower than the 6-inch.

4. Bench grinder wheels

The grinding wheels are the “blades” of your machine and consist of a support with embedded abrasive grains held together by a bonding agent. The structure of the wheel is therefore determined by the type and percentage of the grains and bond agents on the wheel.

There are several types of grinding wheels suitable for light- to heavy-duty demands:

• Aluminum oxide wheels: Are the most common and are usually used for grinding tough metals like wrought iron, carbon steel, high-speed steel, alloy steel, and other similar materials.
• Silicon carbide wheels: Hardwearing wheels used for grinding or sharpening soft metals like brass, cast iron, bronze, but also non-ferrous metals and materials like stone and rubber.
• Ceramic aluminum oxide wheels: Top-notch wheels engineered with high-purity grain. They are much more abrasive than all other wheels and are used for the precision grinding of steel and hard alloys.
• Zirconia alumina wheels: Are similar to the aluminum oxide blades but are made of a blend of zirconium oxide and aluminum They can handle most steels and steel alloys.
• Fine wheels: They aren’t wheels in the true meaning of the word but brushes used for polishing.

5. Which grit size to choose?

Getting the right type of wheel for the job is only part of the puzzle. You must also consider the grit size (which is the size of the abrasive grains on the wheel). There are four grit sizes to choose from:

• Coarse grit: Ideal for rough or heavy-duty grinding operations, it is found on 16 to 24 bench grinder wheels.
• Medium grit: Coats the 36 to 60 bench grinder wheels and serves multiple purposes, from grinding to sharpening.
• Fine grit: Is usually used for finishing touches and it is found on 80 to 120 wheels.
• Superfine grit: It is majorly used for polishing workpieces and it coats the surface of the 150 or higher wheels.

Choosing the right grit size for the job is essential. Coarse wheels work quicker but leave the surface rough while the finer grits work slower but provide smooth results.

Size apart, you should also consider the hardness of the grit which is rated from A to Z with A being the softest. Soft grits are recommended for hard materials, as they tend to grind faster.

6. Why dress the wheels?

Newbies may raise an eyebrow wondering what’s the dressing of the wheels. Dressing a wheel means returning it to its original shape by trimming it. Besides the shape it also exposes new abrasive grains to ensure grinding quality.

A dresser is a tool that slightly trims the surface of the wheel and it usually consists of a bar impregnated with diamond grit.

Dressing maintains the surface of the wheel in good conditions for a long time and represents regular maintenance work. Luckily, the operation is uncomplicated.

To dress the wheel, just keep the dresser tool pressed against the wheel spinning at full speed. This process will remove superficial material and expose new grit for subsequent uses.

7. Other features to look for

Besides all the above, the best bench grinder should also have:

• Adjustable speeds: Not all grinding tasks demand the same spinning speed but don’t just assume you’ll be able to adjust it. A surprising number of grinders have only a single speed.
• Water tray: Workpieces can get very hot during the grinding operation, and it is recommended to keep a container of water near you to cool down the piece as needed. Investing in a model with a water tray means fewer headaches when it comes to storing and accessing the cooling liquid.
• Spark deflectors: The spark deflectors, also known as wheel guards, have the purpose to prevent sparks from flying towards you.
• Eye shield: It is good practice to always wear protective equipment while using a bench grinder, but an eye shield is still a nice thing to have. This piece of plastic mounted over the working area protects you from flying material chips and debris.
• Rubber feet: Most bench grinders can be fixed to the workbench with bolts but rubber feet are still important. They not only keep the unit firmer but also act as cushions between the machine and the worktop, reducing vibrations.