Types Of Die Grinders

Types Of Die Grinders

Last Updated on by Daniel Lawrence

Die grinders are useful tools. They come into mainly two types. You must know these types of die grinders. Knowing the types of die grinders will give you an edge whenever you want to get a die grinder. Read through this guide to find out the types of die grinders.

What Is A Die Grinder?

A die grinder is a small, handheld power tool that has a rotating spindle where a collet holds the cutting bit. The grinding bit that rotates at a very high speed is used for removing material from the workpiece. They look similar to rotary tools and are usually powered by compressed air or electricity.

When combined with the right attachment, die grinders are capable of doing a wide variety of different tasks. Die grinders are primarily meant to work with metal (specifically for Tool and Die making). But one can also use them on other, more sensitive materials like plastic and wood.

With a die grinder and the right attachment on the end, you can polish, sand, cut, grind, or hone various materials. Obviously, this makes the die grinder useful in a lot of different circumstances, as I will show you later on in the guide. Likewise, like many other handheld tools, the die grinder is separated into two different kinds based on their power source.

Die Grinder Uses

Alright, so to help you understand why this particular tool is useful, why don’t I illustrate some of the scenarios where you can use a die grinder? In this section, I’m going to go through some of the more common uses of a die grinder.

  1. Reworking Dies

Ever wondered why it is called a die grinder? The die grinder got its name from the original purpose for which it was developed. That is to grind the dies used in tooling. These include metal stamping dies, plastic molds, die-casting dies, forging dies, etc.

Before the arrival of high precision machines such as CNC milling, EDM Spark Erosion, and EDM Wirecut it was common for the die makers to grind and match the profiles of the mating parts manually. As you know, it is tough to remove material from hardened tool steel with a conventional hand tool such as a file. The die grinder is the best tool for the job since they are small and is to maneuver.

Today toolmakers use die grinder for deburring, chamfering, polishing, grinding, and matching the welded surface, etc.

  1. Polishing Metal

Metal, especially stainless steel, always looks better when it’s polished. Regardless of the object itself, anything metal ends up looking better after you have given it a thorough polishing. But, if the object in question is huge, then polishing it is easier said than done. For example, polishing a car, while possible, can end up being a really long, tiring process. With a die grinder, polishing even vast surfaces can be very easy.

Since the rotary polishing bits are round in cross-section, they are perfect for polishing holes and curved surfaces. The mounting point is regularly used for polishing bits to clean and polish the die profiles.

However, a die grinder is not the ideal tool for polishing flat surfaces, especially if the flatness of the work is important.


Woodworkers or carpenters use die grinders with carbide burrs to sculpt wood into beautiful shapes and great art pieces.

  1. Smoothing Out Surfaces

After finishing something like a woodworking project, you often have to smooth out the final product. This can be tricky, to say the least. Also, you run the risk of accidentally ruining whatever it is that you were working on if you don’t smooth it out just right. A die grinder can be used to smooth out a wide variety of different materials with the correct attachment. You can use it for smoothing out metal, hardened steel, wood, and more.

Weld Spots: If you do metalworking, then you know how annoying welds can be. A die grinder can easily remove the excess welds for smoother, cleaner-looking metalwork. This is definitely a must-have tool if you do a lot of welding or metalwork of any kind.

Why not use an angle grinder instead of a die grinder? Because die grinders are more precise and you have better control over the tool.  An angle grinder is a large tool that is used for removing the surplus amount of material fast. They should be handled with care and are not ideal for precision works. Besides, angle grinders are not suitable to grind inside small holes.

  1. Rust Removal

Rust is both deadly and difficult to remove. It doesn’t matter what the rust infects; it will eventually destroy it. While old rust can be tough to remove from metal, it isn’t impossible, especially if you catch the rust early. A die grinder can be handy for getting rid of stubborn, stuck-on rust. It will do it very quickly, which can be useful if you have a lot of rust that needs removing.


Due to its great smoothing benefits, a die grinder can also replace sandpaper. You can use a die grinder on woodworking projects and it can help to take out rough edges, remove paint or finish, or even create a design or smooth finish of the furniture. Just like removing rust, a die grinder is a faster option to get a professional-looking finish on the wood.

These are some common uses of die grinders. However, there would be many different jobs a die grinder is capable of handling. Auto shops, construction sites, metalworking shops, and other professional worksites use a die grinder for daily tasks.

  1. Sharpening Blades

Many die grinders can be equipped with a blade sharpening attachment; these allow you to sharpen a wide variety of blades. You can use them for knives, hatchets, axes, and any kind of blade that you can think of. They are great for those who don’t own a proper grindstone, but who still want to keep their blades nice and sharp.



The most common die grinders are air-powered. They do use a lot of air, but a small 20-gallon compressor will keep a die grinder running for a long time. Pneumatic die grinders are inexpensive and easy to use and heavy-duty, they offer more torque for heavy material removal and are the preferred tool for machinists and pattern makers.

Air-powered grinders come in several main designs, including straight, 90-degree, and 45-degree. This refers to the angle of the tool head versus the grip. Straight grinders typically offer more control for detail work using grinders and burr bits, while angle-head tools work really well for tight spaces and sanding/surface prep work. The speed of the air-powered grinder is controlled through the throttle on the handle.

  • Pros

High speed. 10,000 rpm means fast material removal with minimal effort on your part. Any type of cutting or grinding bit will work, provided it is rated for very high speeds (wire wheels require more care.)

Inexpensive. An air-powered die grinder can be had for as little as $20, of course, the more expensive ones have better internals and last longer.

Continuous duty. As long as the compressor keeps up, the grinder can run as long as you can.

  • Cons

Air is required. You have to have a good air compressor to run a die grinder, small pancake-style compressors do not have the output to support an air tool like this. A 3-hp compressor with a 20-gallon tank is about the smallest you can get away with.

Hose. You are tethered to an air hose, which often becomes a real problem for the movement. If the hose snags on something, it can cause a big problem. The key to fixing that is to secure the hose to the bench or other solid object and then use a light flexible coil hose from there. This makes a big difference for mobility.


While there are some heavy-duty electric die grinders, most are in the light-duty section. These tools use smaller versions of the same bits for the larger units, with some attachments that are only used with the small electric tools such as router bits. The largest collets (the piece that tightens on the bit) is usually 1/8” for electric grinders.

Remote grinders, where the motor is separate from the tool head and connected through a drive cable, are designed for heavy-duty use. These are really good for intricate machine work where you need a light tool head for maneuverability. These can be single or multi-speed, with or without the foot control.

  • Pros

Portable. The only thing you need is electricity, which can be an extension cord or in some cases, a built-in rechargeable battery.

Lightweight. You won’t have to fight the weight of the tool and air hose because the tools are light.

High-speed. Just like the air tools, electric tools can be spun up to 10,000 rpm or faster.

Unique bits. Router bit attachments for electric grinders make these tools very versatile.

  • Cons

Too small for heavy work, the smaller electric die grinders are too small.

Torquey. The high-powered electric grinders are very torquey, to the point that they can kick out of your hand when you first turn it on. This can be dealt with, but it a key point to be aware of.


Operating a die grinder, regardless of the type, requires a deft hand and firm support. It is very easy for a tool to get away from you, so take care. As with any work where debris can fly, wear eye protection and hearing protection as these tools are loud.