One of the more versatile, but often underappreciated tools out there is the die grinder. If you aren’t familiar with these tools, don’t worry because I imagine you aren’t alone in that regard. Even if people have heard of the name, I think that many people don’t actually know quite what these tools do.
In this guide, I want to tell you everything that you could possibly need to know about this handy, versatile little tool.
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 very high speed is used for removing material from the work-piece. 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, I will also explain how the die grinder, like many other handheld tools, 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 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.
2. 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. I regularly use the mounted point 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.
3. 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. With the correct attachment, a die grinder can be used to smooth out a wide variety of different materials. 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 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.
For further explanation, see die grinder vs angle grinder comparison.
4. 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.
5. 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 other 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.
Is A Dremel A Die Grinder?
One thing that you may encounter when searching for die grinders say online or on a shop website, is something called a “Dremel.” This can be confusing at first since it isn’t evident whether a Dremel is its own separate tool or just another name for die grinder.
The answer is a bit complex. See, Dremel is a brand name, but the brand is so dominant that most people refer to the tool by the brand. A Dremel is just a rotary tool. They are similar to die grinders in terms of what the tool is used for, which is why so many people seem to consider them interchangeable. Both die grinders, and Dremel tools are used for things like grinding material, smoothing out material, sharpening things, polishing items, etc.
However, there are some differences to keep in mind. First off, Dremel tools are generally smaller than die grinders. Dremel tools are a lot easier to hold in your hand and a lot easier to use with only one hand. Die grinders are bulkier, larger, and require you to keep a much firmer grip on them, or you could end up losing control.
Die grinders are also more powerful and able to grind through the material quicker if you want it to be. Dremel tools, on the other hand, are weaker, but also a lot faster. If you’re going to do some more touch-up work quickly, then a Dremel tool may end up being your best option because of how fast it grinds.
Another significant difference is how much variation there is. Dremel tools only come in one version, which is a handheld electric model. As I will go into more depth about, later on, die grinders come in two types, electric and pneumatic. So, if you already have an air compressor set up in your garage, then buying a die grinder makes more sense. There aren’t pneumatic options out there for Dremel rotary tools.
For a more detailed explanation see the 9 differences between a die grinder and Dremel tool.
Types Of Die Grinders
As I have mentioned a few times so far, there are different kinds of die grinders out there. In this section, I want to go over the various types that you can find when shopping for one.
Straight Die Grinders
Straight die grinders are just regular die grinders. They are completely straight and almost resemble a sort of large screwdriver.
Right Angle Die Grinders
Right angle die grinders work the same as straight die grinders, except for the fact that the bit on a right angle die grinder is perpendicular to the body.
Straight vs Right Angle Die Grinder: Which Is Better?
There aren’t actually any pros or cons to the type of die grinder that you pick. Straight die grinders and right angle die grinders work the exact same. So, it comes down to the kind of work you do.
What is a right angle die grinder used for? A right angle die grinder is used to work at tight spaces where the straight grinders cannot fit it. The straight version of the tool along with the cutting bit may be too long to work inside the machine and automobile parts.
Here is an example to illustrate. In figure.1, you can see that it is impossible to grind the hole with a straight grinder.
Fig.1 The straight grinder cannot reach the hole since the gap between the plates is less than the body length of the tool.
In such situations, a right angle die grinder is very handy. It can go in difficult to reach places. See the illustration below.
For most of my work, I use the straight die grinder because it’s more comfortable. If you find a right angle die grinder more comfortable to use for your job, then go for that kind instead.
Die grinders are powered in one of two ways, either electricity or air pressure.
Electric Die Grinders
Electric die grinders need to be plugged-in to work. They are typically less powerful than their pneumatic counterparts, but they also tend to be lighter and a lot quicker. Most professionals that I know prefer using electric die grinders for smaller jobs that require precision and working in tight spaces where an air canister can be a bit cumbersome. It should also be noted that because they are a bit less powerful, electric die grinders can use some unique bits that can’t be used on the more powerful pneumatic die grinders.
There are two versions of electric grinders; corded and cordless. As you can guess the cordless version runs on rechargeable batteries. I am not a big fan of the cordless version of this tool. The batteries add unwanted bulk to the tool.
That said, I can’t deny the fact that nothing can beat cordless die grinders when it comes to portability. If portability is more important for you, then the cordless tool is your best friend.
Pneumatic Die Grinders
If you want raw torque, then a pneumatic die grinder is the better option for you. They are mighty powerful because they harness the power of compressed air. If you have a very large job that needs to be tackled, then a pneumatic die grinder can be a lifesaver. Also, because pneumatic die grinders are so common, they tend to be pretty inexpensive. So, if you are on a budget and already own an air compressor, this is the best option for you.
However, there are some downsides to pneumatic die grinders. For starters, the fact that you have to lug around an air compressor and all that comes with it (hoses, tank, etc.) when using the tool makes it very cumbersome to use, especially if you are in a tight space. Likewise, if you don’t already own an air compressor, then getting one that is also compatible with your tool can be both expensive and a hassle.
Finally, because of how powerful they are, pneumatic die grinders probably aren’t the best option for jobs that require a lot of precision and a soft touch.
Die Grinder Bits
Before ending this article, I want to look at some of the special bits and wheels that you can use on your die grinder.
With your die grinder, you can use:
- Grinding Bits
- Polishing Wheels
- Carbide burr
- Wood Cutting Wheels
- Metal Cutting Wheels
- Grindstone Bits.
- Wire Wheels
- Sanding Wheels
This is just a sample of the various attachments that you can use with your die grinder. As you can see, this is a very versatile tool. I only use a fraction of these attachments, and I still get a ton of use out of my die grinder. So, even if you aren’t going to use all of the accessories, it’s still a worthwhile tool to get.