Buyer’s Guide: How To Choose The Best Belt Grinder For Knife Making

Manual processing of knives does not always provide good surface quality. It requires considerable time and labor. Belt grinders allow you to reduce the time of grinding work and achieve the required cleanliness of the treated surfaces.

How to Choose the Best Belt Grinder for Knife Making 

Belt grinders are the most productive among all types of grinders. A powerful electric motor allows you to take on even the most poorly processed metal bars. Coarse-grained abrasive under the force of the engine can easily remove a thick layer of paint or old rust from the metal.

Before choosing a specific model, you need to determine the area of possible use and possible loads. 

When choosing a belt grinder, you need to pay attention to the following characteristics.

Belt size

The first thing you need to pay attention to is the size of the tape. Based on your tasks, you can choose one of the main sizes:

  • 2×72
  • 1×30
  • 1×42
  • 2×42
  • 2×48
  • 4×36

There are both smaller and larger sizes, but they are less common on sale used for very highly specialized tasks.

All sizes of tapes are widespread, but the most popular size is 2×72 mm. It is the golden mean between power, tape size, and price. 

Motor size

There is a separation by engine power: up to 600 watts, from 600 to 1,000, and over a kilowatt. If you are looking for a typewriter for personal use at home, then take a closer look at small and medium-sized ones – they are more compact and easier to hold in your hand. 

Belt speed

For processing different materials, the speed of linear movement of the tape may differ significantly.

The belt rotation speed varies from 100 to 1000 m/min. Its performance depends on the speed of rotation of the tape. The higher the rotation speed, the thicker the grinder can remove the surface layer.

For knife making, the optimal belt rotation speed is 300-400 m/min.

Variable speed

Many manufacturers install the speed adjustment function. Pay attention to this when choosing since the belt grinder with speed control will be more versatile.

For high-quality grinding, it is necessary to tighten and center the tape properly. Some manufacturers put automatic tension and alignment of the tape.


The most popular are Bosch, Metabo, Makita, AEG. Both professionals and amateurs trust them. 

If you want to buy an inexpensive tool for everyday work, take a closer look at the Einhell, Ryobi, Anchor, Interskol, etc., grinding machine.

Pay attention to the warranty period. Many manufacturers give not one, but two or three years of warranty.

Find out in advance about the availability of a service center in your city and the possibility of buying branded consumables.


If your machine doesn’t have automatic detection of the position of the tape, you need to align it yourself. 

Some devices have a speed controller. For rough and large-scale tasks, you can use the maximum. For delicate ones, you will have to reduce the speed.

Round and Flat Grinding Surfaces

A belt grinder, as a rule, has a high speed of movement of the abrasive element and has high power. After processing wood or metal with a tape Round Grinder, minor longitudinal scratches remain on the surface.

Vibrating flat grinding machines are better for the cleanliness of surface treatment. Low price of tooling. The possibility of using ordinary sheets of sandpaper.

Quick and Easy Belt Changes

Always turn off and unplug before performing repairs. Always read the maintenance instructions!

To install the abrasive material, you should turn over and install the belt grinder on a flat surface. Then install the sandpaper according to the manufacturer’s instructions.

Align it with the outer edge of the drums on the open side. To center the sandpaper, adjust the position of the front drum by turning the adjustment knob.

Connect and turn on the typewriter to check the direction of movement. If necessary, turn it off, disconnect and adjust it again. If the paper does not align, repair the front drum and the support tank assembly.

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Features of a Good Belt Grinder


When choosing according to this parameter, you should proceed from the size of the workpieces you will process. For grinding narrow knives, a model with a tape width of 65 – 75 mm is suitable.

Tracking adjustment

For high-quality grinding, it is necessary to tighten and center the tape properly. If not, the tape will be taken away and chewed. It affects the quality and speed of the work. To make it more convenient for you, some manufacturers put automatic tension and alignment of the tape.


It affects the performance and endurance of the tool. The higher the value, the more intensively you can work. 

If grinding is an auxiliary operation and the tool will work periodically, there is no point buying a powerful one. 


Its performance depends on the speed of rotation of the tape. The belt rotation speed varies from 100 to 1000 m/min. The higher the rotation speed, the thicker the device can remove the surface layer.

For knife making, the optimal belt rotation speed is 300-400 m/min. 

Dust cleansing

Dust protection of the engine and other main components is essential for any grinding machine. Such security is present in professional models, as it increases the resource of the tool. Accordingly, it significantly affects the price of the instrument.

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Machine and Abrasive Maintenance Issues 

Mistake #1. Too dusty

If there is no dust removal system on the grinding machine, the device may not just stop working. It may explode. Dust clogs optical sensors. The tapes can go off the shafts to the side and tear. Dust gets into the application areas of the soil and varnish. It can affect the quality of the product.

Mistake #2. Tape storage

Tapes cannot be stored on a wet floor because the paper collects moisture. One edge of the tape lengthens. Thus, a cone of up to 5 mm can appear. And these millimeters are enough for the video to come off the machine and not work. 

Mistake #3. Constant tension

The contact shafts are rubberized. If the belt grinder does not work, the rubber deforms. As a result, defects appear on the surface of the processed workpiece or, as still happens, the engine shakes. It is especially evident after a long weekend or an extended downtime of the device.

Mistake #4. Uneven load

The load should be equal so that the entire set of belts wears out simultaneously.

Mistake #5. Lack of lubrication

After grinding, waves remain on the workpiece. Often the problem lies in the contact shaft of the machine and not in the seam of the tape.

Wide Belt Sander Visual Defects

Surface defects

Surface defects resulting from improper use of wide belts can significantly negatively impact the result of using Wide Belt Sander.

Transverse ripples

Quite often, on polished surfaces, you can see uniform ripples completely covering them. Two different reasons can cause such waves:

  • Due to insufficiently rounded (or damaged) support rollers;
  • From the impact of the seam of a poorly glued sanding belt.

Equipment defects

The appearance of long strips is prevented, as a rule, by regular maintenance and control of machine elements, especially the clamping shoe.

Thin strips

Thin strips are elevated, in most cases interrupted, thin strips on the part’s surface in the feed direction. The cause of their occurrence is damage to the grinding dusting by mineral or metal inclusions that have got into the pieces.

Tape break

The reasons for the occurrence of transverse breaks of the tape can be:

  • Improper operation of the tapes;
  • Poor quality of machine settings;
  • Poorly executed adhesive seam on the tape.


Wrinkling looks like characteristic cuts passing to the direction of movement of the tape. The reason for their occurrence is a too fast movement of the oscillation of the tape.

Tape Offset

The lateral displacement of the tape can appear because of conical gluing, that is, by the fact that the opposite edges of the tape have different lengths. 


What is the difference between a belt sander and a belt grinder?

People use belt grinders to work with aggressive works like knife making. Belt grinders can operate with metals metal, concrete, and wood. 

A belt sander is a more acceptable for softer materials like wood. However, you still can sharpen knives with it.

Can you use belt sanders for knife making?

The most suitable tool for knife making is a belt grinder anyway. It is universal but rather expensive. 

People use belt sanders mainly for grinding wood, and the tapes used in them do not handle steel well, specially hardened steel. You will need much more time to make a knife than when using a grinder.

Final Words

A belt grinder is an electromechanical tool used for grinding wooden, concrete, and metal bases. With the help of the belt grinder, you can effectively and quickly remove the old paintwork from metal. The belt grinder is capable of any area processing and performing primary and intermediate grinding on it. 

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