The Best Die Grinder for Small Details
Die grinders aren’t heavy-duty tools for knocking off weld slag like a right angle grinder. Rather, they’re detail tools, for those times where finesse is needed more than power. The small size and light weight of these tools make them ideal for fine finishing work, something that’s hard to do with a right-angle grinder.
Typically, a die grinder uses a 1/4 inch collet for holding a variety of tips. However, some of the smaller units such as cordless ones and pencil grinders use a 1/8 inch collet. Best die grinders in 2021 work with a wide variety of tips including grinding wheels, carbide cutting tips, sanding disks, and cut-off wheels. With the variety of tips available, these tools are very versatile and good for a wide variety of tasks.
Whereas angle grinders are normally only used for metal working, die grinders (especially the smaller ones), have found a number of other niches including jewelry making, crafts, model making, and anywhere else a small cutting or grinding tool is needed. Our buyer's guide listed below can help you to pick the right die grinder for your needs.
AIRCAT Red Composite Angle Die Grinder
Astro Pneumatic Die Grinder
Chicago Heavy Duty Air Die Grinder
Ingersoll Rand Air Die Grinder
Astro Pneumatic 218, 1/8 Inch Pencil Type Die Grinder
Makita XDG01T 18V 4" Kit Die Grinder
Milwaukee 2460-21, M12 12 Volt Rotary Tool Kit
Dremel 8220-2/28, 12 Volt Max Cordless Rotary Tool
Best Die Grinders Worth Considering in 2021
Aircat produces some of the quietest air tools on the market, and this die grinder is no exception. They've taken a new look at die grinder design, creating an ergonomically friendly design, in a composite shell. The light weight and shape of this tool are wonderful for working long periods of time. Being a right angle die grinder, it offers better control for the user. That couples nicely with the feather trigger, allowing precise speed control. A rear exhaust makes the lower sound level possible, while also ensuring that the exhaust isn't hitting the operator in the face. The motor turns at a maximum of 20,000 RPM. High quality construction throughout ensures a long work life.
Okay, I have to admit, I’m cheating a bit on this one. When I ran into this kit from Astro, I thought it was perfect. Not only do you get a right angle die grinder, but it also offers a straight one as well. So, if one style of grinder doesn’t work out well for your project, the other will. Both are part of their ONYX series, with composite, ribbed handles for light weight and less vibration while maintaining a good grip on the tool. The lever throttle handle provides feathering control of speed, and is also a safety handle. This one is also rear exhaust, like the one form Aircat. The straight die grinder operates at a maximum speed of 25,000 RPM and the angled one at 20,000 RPM.
If you do a lot of grinding, especially a lot of heavy grinding, then this is the die grinder for you. Most die grinders are only 1/3 HP, while this one, from CP is a full 1/2 HP. To put it another way, that’s 50 percent heavier duty than the competition. That extra power helps cut through tough problems and will also help ensure that the tool lasts longer. In fact, CP is so confident in this tool, that they've recently upgraded the warranty to two years. It comes in an aluminum body for durability, with a squared-off handle to make it easier to hold onto. The exhaust is out the rear, keeping the exhaust air and any oil away from the workpiece. A built-in regulator helps you match the 24,000 RPM speed to the work. It comes with both 1/4-inch and 6mm collets.
Ingersoll Rand is a brand that the manufacturing industry has grown to trust. Their tools are all well designed, for rugged use and long life. This is proven out in this die grinder, which is built with ball-bearing construction. This is the highest speed die grinder we’ve looked at, with a maximum speed of 27,000 RPM. The composite case is ergonomically designed for comfort. The throttle is self-locking for safety. Like the others we’ve looked at, this one has a rear exhaust; a must for die grinders.
I had to include this grinder, because it is rather unique. While there are a few other pencil style die grinders on the market, they are hard to find. Of all the pencil die grinders around, I’d have to say that this is the best. Working with it reminds me a lot of using my flex-shaft. This compact unit runs at a maximum speed of 56,000 RPM. A twist throttle on the grinder allows you to control that speed, setting it where you need it and leaving it there. The collet is 1/8-inch, not the 1/4-inch that is common for the other die grinders we've looked at, so finding bits for it might be a bit more challenging. However, when you've got to work in a tight space, this pencil grinder is ideal.
There's a lot of attention to detail in this grinder from Makita. A stepped neck design makes it easier to get into tight spaces and even the collet nut is rounded, reducing the possibility of damage. At 25,000 revolutions per minute this grinder removes materials rapidly when needed while electronic controls protect the motor and help maintain speed under load. The power switch is a slide-lock design, rather than a paddle switch that the operator has to hold on, helping reduce operator fatigue. The solid aluminum housing adds durability, vents are cut into the unit to blow away from the operator, and the barrel-grip design is compact and lightweight at only 4.4 pounds. With Makita’s fast charging time, the two 18 volt batteries for this tool are always ready to go and a low battery indicator LED flashes when it’s time to recharge.
Milwaukee calls their mini die grinder a “rotary tool,” but it’s essentially the same thing. This compact unit weighs only 1.3 pounds and comes with a 1/8 inch collet. It is a variable speed unit, ranging from 5,000 revolutions per minute all the way up to 32,000 RPM, making it the fastest cordless die grinder around. The 12 volt battery recharges in 30 minutes to get you back to work as quickly as possible.
Most people don’t think of a Dremel as a die grinder, but in reality, that’s what they are. Like all Dremel tools, this one has a 1/8 inch collet. This is Dremel’s most powerful cordless model, with a high performance motor and a one hour charge time. The 12 Volt Li-Ion battery is replaceable like other die grinders, not something all that common for Dremel. It’s variable speed, ranging from 5,000 revolutions per minute up to 30,000 with a convenient speed control. The unit is made with all ball-bearing construction for longer life and cooler operating temperature.
The die grinder is the smallest of the various types of grinders that are made. Unlike the larger grinders, these are not intended for rough cutting as much as they are designed for detail-oriented work. Their high speed and variety of tips make them an ideal tool from fine finishing of a workpiece to adding details to the shape by hand.
Die grinders depend upon high speed for their cutting power rather than brute force. These tools are typically low power units, 1/3 HP or less. However, they run at speeds of 20,000 RPM or more with a few units that top 50,000 RPM. At those high speeds, it’s easier to do the fine detail work these tools are known for.
Options Available for Die Grinders
These tools are rather simple, without a lot of options to choose from. The options actually come about in the type of tip you put on the die grinder. However, there are some things you might want to consider when looking for a die grinder.
Die Grinder vs. Cutoff Tool
Die grinders are often sold as cutoff tools with the addition of a guard and the installation of a fibrous cutoff wheel. With a cut-off wheel, a die grinder can be used to cut metal bar stock and tubing. If you buy a die grinder, rather than a cutoff tool, you can easily convert it for cutting off metal bar stock and tubing by adding a shield to protect you from hot metal sparks. The only difference between a die grinder and a cut-off tool is this shield.
For this reason, you might want to consider buying a cutoff tool rather than a die grinder because that way you already have the shield. Just verify the tool comes with a 1/4" collet and that its speed is equal to the die grinder.
Variable Speed Control
Many die grinders are designed to allow the user to control the speed, even though they’re typically used at full speed. However, when cutting or grinding softer materials the variable speed helps prevent overcutting and potential destruction of the workpiece.
Straight vs. Right Angle
Traditional die grinders are straight, with the tool rotating perpendicular to the length of the tool. More recently, manufacturers have started making right angle die grinders and there’s even one manufacturer making a die grinder built at 30 degrees. While the angled head is easier to hold for some types of operations, both styles have their place.
These angled die grinders shouldn’t be confused with angle grinders which operate totally differently. A right angle grinder only works with grinding wheels which mount to a shaft. A right angle die grinder still has a collet for the various types of tips to mount into.
Pneumatic or Cordless
As with many other power tools, cordless die grinders are now appearing on the market, for portability and ease of use. While cordless die grinders are longer than pneumatic ones, the not having to drag around an air hose or power cord makes it possible to get into areas with where pneumatic die grinders simply can’t reach.
Like most cordless tools, cordless die grinders are used more by contractors on remote jobsites, than by people working in a shop. The advantage of working off of battery power isn’t as apparent when you are in a shop with air power piped throughout. Pneumatic die grinders will run virtually indefinitely off of shop air as they use very little air. In the same situation a cordless die grinder would require stopping to change the battery periodically.
A sub-category of die grinders are pencil grinders. These are designed using a 1/8" collet, rather than a 1/4" one. The smaller collet allows for smaller cutting heads for finder detailed work. Typically these will be smaller, making them easier to hold like a pencil and use in the same way.
Pencil grinders come in pneumatic, electric and cordless. The electric ones may have the motor separate from the grinder head, running power through a flexible cable down to the head. This "flexible shaft" pencil grinder is popular with model makers and jewelry makers who need to do fine detail work without having a large motor-driven tool in their hands.
The dremel tool actually falls into this category although it has a larger body. Nevertheless, it comes with a 1/8" collet designed to be used with the same types of tips used on other pencil grinders. Even though it’s larger in diameter, the casing is designed to be ergonomic so it can still be held like a pen and used as easily as the other types of pencil grinders.