Best Angle Grinder
Angle grinders were first developed for use with welding, removing weld slag, excessive weld metal, and burrs from the metal. Since them, creative users have found a myriad of other uses for angle grinders, using them for everything from creating ornamental patterns in metal to finishing concrete work.
Angle grinders are built on a 90 degree angle to provide the best possible torque and the best user control. By running the motor through a 90 degree gearbox, the grinder’s torque is increased. This helps prevent the grinder from binding up when encountering difficult spots in the work. It also makes it possible for the user’s hands to be at a comfortable position, while providing a clear view of the grinding wheel to work piece contact.
Before making your selection, you may want to take a moment to look at our buyer's guide provided below and see the factors which make the difference between a ho-hum angle grinder and a top notch one.
Best Angle Grinder:
While not a part of every handyman’s toolbox, angle grinders are a very useful addition. They’re mainly used for cleaning up weld slag and splatter but the utility of this handheld power tool doesn’t end there. Angle grinders can be used anywhere where grinding is the best way for removing material such as cleaning up concrete work, cutting metal pipe, tile work, cleaning oxidation and just getting off crud from a variety of surfaces.
The basic grinding wheel is a pressed stone wheel but there are a number of other variations which can be attached to this tool. Most commonly these are aluminum oxide wheels, cutoff wheels, and wire brushes, each of which is useful in different applications.
Angle grinders come in different sizes, ranging from a small end of 4 ½” to a large end of 9”. While the larger tools require a larger motor, the overall tool design is essentially equal across models. The motor is run through a right-angle gearbox connecting to the wheel. The gearbox makes the tool more convenient to use while reducing the possibility of the tool becoming bogged down from excessive friction or “pinching.”
Most all angle grinders come with an auxiliary handle which can be attached to either side; an essential feature as these tools can be very hard to control. They also have a blade guard which covers about the back third of the blade facing you. While many people remove these blade guards, it isn’t recommended, as the chips and sparks coming off the blade can harm you. The guard also provides a convenient way to lay the tool down which otherwise can’t be done until the wheel on the grinder comes to complete stop. Due to the sparks and chips these tools produce, it is always recommended to use safety goggles and leather gloves when working with an angle grinder.
When picking an angle grinder, the first decision you need to make is the size you want. Larger angle grinders cost more, but remove material faster. Since this list deals with the best, we’re only looking at 7” and 9” angle grinders so if you need a lower cost angle grinder, take a look at our Best Budget Angle Grinder List.
In addition to size, the other major factor when choosing a model is its durability. Unlike most handheld power tools, angle grinders are normally on for longer periods of time. Where a circular saw may be on for two minutes tops, an angle grinder might be on upwards of 20 minutes. This wears bearings, gears and brushes much faster than for saws and drills. You’ll definitely want to ensure the grinder you buy has easily replaceable brushes readily available on the market.
This grinder's high speed sold me on it for the top spot on our list. As with other Bosch grinders, the service minder brushes will stop the tool from working when the brushes need replacing so you won’t damage the motor. Read Full Review
This DeWalt has a lot of the same features as the Bosch including the automatic stop feature when the brushes are worn out. The power and speed are the same, but this tool is a bit heavier. Read Full Review
Like all Milwaukee power tools, this angle grinder is heavy duty with a 4.2 HP motor running at an optimal 6,000 RPM. They've designed a special baffle system to keep dust out of the motor while allowing cooling air in. Read Full Review
The "soft-start" feature helps make this tool much more comfortable to work with than most angle grinders. Like everything that Makita makes, this one is well designed, for long life and user comfort. Read Full Review
Best Budget Angle Grinder:
For those who only need an angle grinder once in a while, buying a budget one is a viable option. However, if you’re doing a lot of welding or other work which would require the use of an angle grinder, then invest in a good one, as it will cut faster and last longer.
These budget grinders are all 4-1/2” in diameter. For the average handyman, who doesn’t need an angle grinder all the time, their small size will serve you well. While these lower cost models won’t last you as long, you probably won’t have a problem if you’re not using it all that much. While a budget angle grinder will save you money, it’s important to be aware of their various issues.
The first issue is the brushes tend to wear out so you’ll want a grinder with easily replaceable and procurable brushes. Buying a niche brand can make it difficult to find replacement brushes, turning your budget grinder into a piece of disposable junk. If you can, buy extra brushes when buying a grinder, to ensure replacements are easily at hand.
The second issue with budget grinders is the gearbox which tends to wear out quickly. It’s an area where manufacturers cut costs by using smaller gears made out of less expensive materials. You can greatly prolong the life of even the cheapest angle grinder, by opening the gearbox and filling it with grease. Use caution however, these gearboxes aren’t sealed well, so the grease will likely ooze out during storage. Be sure to put a rag under the grinder to catch that grease and avoid a mess.
The third issue is the bearings. Budget angle grinders usually have sleeve bearings, as opposed to roller bearings. There are two things you can do to help here. First, squirt a little bit of lubricating oil into the bearings every once in a while (avoid getting it in the motor commutator). The second is to avoid overheating the motor. When it becomes hot to the touch, stop and allow the unit to cool off.
If you follow these guidelines, you should be able to get several years of intermittent use out of your budget angle grinder, without serious problem.
Angle grinders come with two types of switches. The first is what’s known as a paddle switch, which is a lever or paddle held down with the pinkie and/or ring finger. The second is a slide switch, which is operated by the thumb and comes in locking and non-locking versions. The lock-on slide switch stays on even if you lose your grip on the grinder creating a safety issue while the non-locking slide switch puts the thumb in an awkward position. Given a choice between the paddle and slide switch, the paddle switch is recommended; it’s easily held, and shuts off whenever you let go of the grinder.
Another important factor is the ease of changing the cutting wheel. Most have blade locks and use a special spanner wrench (supplied with the grinder) to change the wheel. A few use a hex nut, which means that you don’t have to keep track of that spanner.
The budget angle grinders considered on this list have a street price of less than $100. Don’t be put off if you see a higher price on one, check around, you can probably find a good deal somewhere.
Always be sure to use safety goggles when using an angle grinder. These tools put off a lot of sparks and chips, which can cause serious damage to the eyes. As uncomfortable as safety goggles are, they are much better than losing an eye.
DeWalt shows their concern for the details in this grinder by providing a trademarked Dual Ejection System to keep dust and debris out of the motor and bearings. The grinding wheel and guard are both changeable without any tools. Read Full Review
Bosch just recently released this grinder, an update from the previous model. In the process, they gave it a little bit bigger motor, adding a half an amp. Read Full Review
The all ball-bearing motor on this tool from Makita helps ensure long life. It's also got an extra-large paddle switch, making for more comfortable operation. Read Full Review
Lighter and smaller than the other grinders we looked at, this model from Hitachi is only 3.1 pounds. That, combined with the rubber overmolded barrel cuts down on operator fatigue. Although not as powerful as the other models, for the home user, this grinder has a great price. Read Full Review
Best Cordless Angle Grinder:
If you do any work with metals (Such as welding or making modifications to vehicles) you’re eventually going to need an angle grinder. Angle grinders are the portable version of your venerable bench grinder, tools made for shaping, cleaning, and modifying metals. Angle grinders are essential for welding where they are used for cleaning up weld slag and splatter. If you’re doing any welding work outside of your workshop, a cordless angle grinder can save you a lot of hassles. We’re talking one very versatile tool to have around.
What could be more convenient than a cordless angle grinder? Just like all other electric hand tools are going cordless, so are angle grinders. Being cordless makes them ideal for those times when you’ve got to do something quick, and don’t want to take the time to dig out an extension cord and hook up a regular angle grinder.
While it’s normal to put a standard grinder disk on an angle grinder and leave it until it’s worn out, you can actually fit it with a variety of grinder disks, cutoff wheels, and wire brushes. Don’t limit your angle grinder to one role! Experiment with other ways to use your grinder and buy the necessary accessories to take advantage of its versatility.
Like all other cordless tools, the biggest issue using a cordless angle grinder is battery life. However, with lithium-ion (Li-ion) batteries and a quick charger, your cordless angle grinder won’t be down for long. These tools work exceptionally well with Li-Ion batteries since these battery types allow your tools to keep running at full speed, right up until the battery is ready to quit. Considering how speed greatly affects how quickly they cut, the Li-Ion batteries work much better in these tools than the old Ni-Cad batteries ever did.
For this list, we’re looking at combination of features as we would with any cordless power tool. More than anything, we’re looking at a combination of power and speed as these two factors will affect the cutting speed of the grinder. Higher voltage cordless tools generally have more power, so they won’t get bogged down if you put pressure on them. In addition to those basics, I’m looking for cordless angle grinders with the greatest durability, operator comfort, and battery life.
Milwaukee tops our list with the most powerful cordless angle grinder on the market. Running off a 18 volt Li-Ion battery, this model delivers enough torque so you can really bear down on the metal and get the job done. Read Full Review
This is the fastest angle grinder on our list at 10,000 rpm. That extra speed equates directly to faster cutting speed. As with all Makita tools, this grinder unit has quality written all over it and includes a built-in over-torque protection circuit which is an especially nice feature. Read Full Review
This is a very well-designed tool from Porter-Cable. I like the handle which protects your knuckles from getting scraped up going over the edge of a piece of metal which I've done that more times than I care to think about. Read Full Review
DeWalt has come out with the first totally tool-free wheel changing on an angle grinder. This solves perhaps the biggest problem with these tools; losing the special wrench most angle grinders require for wheel changes. Read Full Review
If you're looking for a light tool, look no further than this 4.2 pound Hitachi grinder. This company is known for building convenience into their power tools demonstrated by this units easy access carbon brushes and designing the tool so it accepts all Hitachi's battery types. Read Full Review
Angle Grinder Buyer's Guide
Angle grinders are one of the few handheld power tools designed primarily for metalworking. However, they’ve since been found to be useful for a variety of other purposes. Replacing the grinding wheel with different mediums allows it to be used tasks ranging from concrete finishing to removing decals from vehicles.
The angle grinder is a fairly simple tool with an electric motor run through a right-angle gearbox. The output of the gearbox then becomes the arbor for attaching the grinding wheel or other medium. By using a right-angle gearbox, the tool becomes much more ergonomic to hold onto, making it both more comfortable to use and much easier to control.
Typically, they’re held two-handed, providing excellent control. The other thing the gearbox does is reduce the chance of the tool binding up from too much of a load being placed on it.
While simple, the angle grinder is a very effective tool. When used for metalworking, it’s used predominantly used for smoothing and grinding welds, removing weld splatter, slag, and excessive weld. The high tool speed and rough grinding medium allows it to work quickly.
A variety of grinding wheels and other attachments can be connected to a grinder, each of which is designed for working with particular materials and performing particular tasks. These include grinding wheels for different materials, metal cutting wheels, wire brushes, polishing bonnets and Scotchbrite pads for cleaning and paint stripping.
Of all the handheld power tools on the market, angle grinders provide the least protection for the user. The guards on these tools are minimal and only cover the back side of the attachment, the side facing the user. It’s typical to produce a large amount of sparks when using a grinder so protective goggles and gloves should be used. It’s also important to ensure the tool has come to a complete stop before setting it down.
Selecting a Grinder Size
While there are several sizes that angle grinders are made in, they basically fall into two categories, small and large. The small ones range from 4” to 5” and the large from 7” to 9”. Smaller grinding disks can always be attached to a grinder, but larger ones can’t. It’s also important to take into consideration the maximum speed of any particular attachment.
Grinders rotate at high speed and the attachment must be able to withstand the rotational force without coming apart. These attachments typically have the max RPM stated on them to provide the user the ability to properly selecting their attachments.
While two angle grinders may have the same rotational speed, that doesn't mean they’ll provide the same amount of cutting action. A larger grinder will be moving faster at the edge, as measured in feet per second than a smaller grinder moving at the same RPM. This makes the larger grinders cut faster, giving them preference for commercial use.
This increase in cutting size means that you should pick the largest grinder that you can reasonably fit within your tool budget. That will ultimately save you time and have the tool pay for itself.
What to Look For in an Angle Grinder
When selecting a grinder, power and size are the two major considerations. The higher power allows you to put more pressure on the grinder, making a bolder cut. While speed and wheel size are important factors in grinding capability, the amount of pressure placed on the point of contact with the workpiece is important as well.
Operator comfort is also an important factor when selecting a grinder. Tool weight, adjustable handle positions and over-molded rubber handles all play a part in operator fatigue. While not usually the number one factor when selecting tools, these factors shouldn’t be ignored.
When buying inexpensive angle grinders, one of the best things you can do is to open up the gearhead and fill it with grease. The gears themselves will probably be greased, but by adding more grease you will help to cool the gears and allow them to last longer.
Of all power tools, angle grinders go through motor brushes faster than any other. This probably has to do with the fact that when these tools are used, they’re typically on for extended periods of time. Ease of brush replacement and availability of replacement brushes are both important factors for cases where the grinder will be used a lot.
Besides the two different size ranges of angle grinders that are available on the market, there are also cordless grinders. These are only available in the smaller size range, as the larger grinding wheel requires more power to operate.
Cordless grinders are great if you are working on a remote site, but can be a bit of a hassle in a workshop. Generally speaking, when angle grinders are in use, they are on for an extended period of time. Even though cordless angle grinders use Lithium-Ion batteries, the batteries can only power the grinder for a certain amount of time. If you’re using the grinder continually, you will probably need a total of three batteries and two chargers to keep the unit operating constantly.