Electric grinders

It's a must, but
There are nuances
An electric sander is a tool used to grind, cut, shape and polish various materials such as metal, wood and plastic. It usually consists of an electric motor that drives a rotating abrasive wheel, belt or disk. The motor rotates the abrasive surface at a high speed, which can effectively remove material from the workpiece. Electric sanders can vary in size and power, and some are equipped with speed control knobs and a reverse switch. There are many options on the market today from brands such as Craftsman, Bauer, Dayton and others, for every application and budget.
When considering electric benchtop grinders, some may confuse them with electric sharpeners. So what is the difference? An electric grinder and an electric home sharpener serve different purposes.

Electric grinders:
- Used mainly for sanding and shaping various materials.
- Consists of a motor that spins a grinding wheel, belt or abrasive disk at high speed.
- Electric grinders are commonly used in workshops, construction sites and manufacturing plants to perform tasks such as cutting, grinding, polishing and sharpening tools.

Home electric sharpener:
- A home electric sharpener, on the other hand, is specifically designed for sharpening blades, knives, scissors and other cutting tools commonly found in the household.
- It usually features slots or abrasive surfaces that guide the blade at the desired angle against rotating sharpening stones or disks.
- Home electric sharpeners are more compact and convenient to use as compared to industrial sharpeners. They are designed for easy and safe use by people who do not have much training or experience in sharpening tools.
- These sharpeners often have several grades or grits, allowing you to gradually refine the edge of the tool.
Can you see the difference between these two?
Electric sanders come in a variety of types and sizes, each designed for specific tasks:

1. Angle Grinder: This type of electric grinder is of manual construction and features a rotating abrasive disk perpendicular to the motor shaft. Angle grinders are commonly used for cutting and grinding metal, tile and concrete.

2. Bench grinder: Bench grinders are larger stationary tools with abrasive disks mounted on each end of a rotating shaft. They are mainly used for sharpening tools, shaping metal, and other precision grinding tasks.

3- Grinder: Grinders are compact electric tools with straight or angled grinding wheels. They are commonly used for complex grinding and shaping tasks in metalworking and woodworking.

4. Belt Grinder: Belt grinders use a continuous abrasive belt wound on two pulleys to grind and polish surfaces. They are often used in metalworking to shape and finish metal parts.

Electric grinders are widely used in workshops, construction sites, manufacturing and even by hobbyists to perform various tasks such as cutting, grinding, polishing and sharpening. They are characterized by high efficiency and precision, which makes them indispensable
At Mr. Sharp we use electric belt grinders and other electric sharpening machines to sharpen knives, garden tools, workshop tools and much more with maximum efficiency!

What is the difference between sharpening on a machine and sharpening on a sharpening stone?

The main difference is speed. If you have a knife that needs to be reshaped, you can spend hours grinding material off the blade with a stone, whereas an electric sharpener will take seconds. If the blade has nicks or the cutting edge is severely dull, even a coarse-grained sharpening stone will not do the job easily.

But speed can also play against you. A typical electric sander spins the abrasive disk or belt at ~3450 rpm. If you're not careful, you can damage the blade, requiring additional repairs. You can also overheat the blade if you press the blade too hard or too long against the abrasive material. To use your sander effectively without causing additional damage, you need to think fast.

On an electric sharpener, it's easier to set the right angle. If you spend less time sharpening one knife, you'll have a better chance of setting one angle for the entire cutting edge without making it inconsistent and wavy. You will have more room for error if you grind down a lot of material with a sharpening stone. Muscle fatigue and impatience will affect the end result regardless.

Can you see that the bolster is lower than the cutting edge?
Dayton electric grinder with a superfine belt.
I used to be convinced that sharpening on a sharpening stone was better than sharpening on a machine, but I was wrong.

Electric belt sharpeners have different belts that can sharpen and polish the cutting edge just as well as whetstones do. During my certification with the National Sharpeners Guild, I learned that it's not as important as the grit of the sharpening tools. If you have a 6000 grit stone for your cutting edge, you can achieve similar results using a fine grit belt.

If you take two knives and sharpen one on a machine and the other on a whetstone, the knife sharpened on the sharpening stone may stay sharp a little longer because of the scratches left on the cutting edge. An electric sharpener will leave deeper scratches compared to sharpening on a stone, which will affect the longevity of the cutting edge.

If you use a sharpening stone, you can better control the amount of material coming off the knife. This is more difficult to do with an electric sharpener because of the rapid sharpening process.

Finally, the type of steel your knife is made of plays a crucial role in how long your knife will stay sharp. Cheaper materials will round out and dull faster than high quality steel.
You can clearly see the burr at the tip of the knife.
It is worth noting that after sharpening on an electric grinder, a burr remains, which must be removed before returning the knife to the customer. To remove it, we use a leather strop. It takes several passes to remove the burr, but the drastic difference pays off.

We take our time with each knife to make sure the burr is removed. When the job is done, run your fingers along the cutting edge without applying pressure. If you feel a burr, it means the knife is not ready to be used.

If you leave a well-polished cutting edge, it will stay sharp longer than a one with a burr.

When choosing between an electric sharpener and a sharpening stone, you should also consider noise and dust levels. An electric sharpener, in my opinion, is considered a heavy weapon in the sharpening game. When you sharpen 100-200 knives, your workshop will be filled with metal dust that will have to be cleaned up. It will cover everything in the room, including shelves, walls, and floor. This does not happen if you use a sharpening stone.
At the end of day, it doesn't matter what tools you use to sharpen your knives and tools. Your skills, time, and effort matters.