Cut-off Tool vs Angle Grinder (Difference & Uses)

In the metalworking world, two of the most common tools we come across are the Angle Grinder and Cut-off Tool. Both of these tools are used for the purpose of cutting steel, but they do have some significant differences in their functionality and practicality.

In the following text, we shall investigate some of these differences and try to help you to evaluate which will better suit your project.

Difference Between an Angle Grinder and Cut-off Tool

To keep it clear and simple, the most obvious difference between the angle grinder and cut-off tool is found in their differences in flexibility. The angle grinder can be used not only for cutting but also for the grinding, sanding, polishing, and weld prep of metal while cut-off tools are only useful for cutting steel. Additionally, we see many further differences between the two however, we shall investigate these further on.

What is a Cut-Off Tool?

A cut-off tool is a lightweight hand-held tool that is approximately 6 inches in length that specializes in the cutting of steel. It consists of a cutting disc (wheel) which is usually about 3 inches in diameter and depending on the model, can be positioned length-ways to the tool’s body or parallel.

The difference between the models that have a disc located length-ways vs parallel is the overall accessibility to the job at hand. This in fact proves to be highly advantageous when attempting to cut metal in locations that have limited accessibility.
Types of Cut-off Tools. Photo by: Keith Homan/Shutterstock.com

What Is Cut off Tool Used For?

Cut-off tools are used for the cutting of metal that is generally no thicker than 1 inch. They are also excellent for making cuts in locations that are difficult to reach which makes them extremely practical for panel-beating and sheet metal fabrication situations. However, their usage is restricted with the cutting of heavier metals due to power limitations and disc diameter.

Sometimes referred to as a disc cutter, you can use this power tool to cut plastic, soft metals such as aluminum, brass, hard materials such as stainless steel etc.

Cut-off tools are most often powered by electricity, pneumatic power, or air pressure and have a power range usually maxing out at 1HP.

Note: Do not get confused with a metal cutting chop saw which uses a much larger abrasive cutting disc mounted on a hinged arm.

What is an Angle Grinder?

An angle grinder is a multi-purpose tool used for grinding, sanding, polishing, and weld prep of metal. It comes in various sizes with discs ranging from 4.5” (115mm) and 9” (230mm) with motor sizes that vary from 3-7hp, this makes them highly versatile and useful for heavy-duty applications and more delicate work alike.

Unlike cut-off tools, the disc of the angle grinder is always located parallel to the grinder’s body which does limit their accessibility at tight spots. However, despite this limitation, they are still highly useful for all manners of jobs and can be used upon materials such as metal, plastic, wood, and masonry products. The versatility and the uses of an angle grinder are discussed in detail here.

The most common and practical way to power an angle grinder is via electrical input; however, lithium batteries are also useful for working in locations without accessible electricity but they prove to be fairly limited in their power range.

Angle Grinder vs Cut-off Tool

The following comparison table should give you a quick summary on how these two power tools compare each other.

Functions

The primary functions of the cut-off tool revolve completely around the cutting of metal rods, bolts, rebar, and other cross-sections to the desired length.

On the other hand, an angle grinder is a very versatile tool. You can use an angle grinder for cutting metal, grinding, sanding, polishing, deburring, and weld preparations.

Although the grinder is a much more useful tool, when discussing the field of its application, the cut-off tool is superior with its accessibility to hard-to-reach locations.

Depth of Cut

The cut-off tools have a 3-inch abrasive cutting disc which can cut up to a depth of 1-inch. Some models with right angle orientation are limited to a depth of cut of ¾ -inch.

The angle grinder is highly versatile when concerning material thickness and size and is not extremely limited in its accessibility as machine sizes differ to suit. A 9 ″ angle grinder can cut up to 3.5 inches deep.

Size

A disc size of 3-inches is the standard for most of the cut-off tools (which corresponds to its limited verbality in cutting thicknesses). This tool has a very compact and lightweight design; thanks to the smaller disc size and corresponding smaller motor.

With disc sizes ranging from 4.5 inches to a huge 9 inches, angle grinders have a variety of different sizes to suit each specific job.

Power

These tools are usually powered by compressed air or electricity. An electric cut off tool has a mere 1HP average is a fairly low power input from a power tool. This is useless with tougher and thicker materials.

Angle grinders have a power rating ranging from 3HP – 7+HP the range of angle grinders is wide and practical for all projects.

Speed

Cut-off tools can run at very high speeds ranging from 18,000 to 28,000 rpm. While they do not have the power of a grinder, they excel in speed.

Grinders have much slower speed ranging from 6000 to 8000 RPM with some models going up to 12000 RPM.

Safety

The safety guard on the cutting-off tool covers less than half of the wheel which increases the risk of the tool kicking back onto the user. However, despite this, its small size means the potential injury has lesser impact and dust/noise pollution is minimal when compared to grinders.

Safety guards are a common accessory with all the angle grinders and when used correctly, they protect the user from injury. If an injury does occur from grinder kickback, however, it is usually severe.

Dust/noise pollution is more recessive when compared to cut-off tools.

Although the use of safety guard and personal protection equipment like safety glasses can protect you, keep in mind that improper use of abrasive cutting tools can be very dangerous. Follow the grinder safety instructions and tips very carefully.

Price

Both tools are relatively inexpensive. You can find cut-off tools as low as $40USD for a model with very basic capabilities although for a heavy-duty cordless model expect to pay at least $80 USD or more.

Slightly more expensive are angle grinders with basic models costing approximately $50USD

Which Tool Should I Get?

When to Purchase a Cut-Off Tool?

One should consider the cut-off tool as their primary choice of cutting tool because two or more of the following factors are important to you or your project:

• The material cross section to cut is not more than 1 inch.
• You are on a very low budget
• The cut is located in an area of difficult accessibility
• Where user safety or pollution is of a concern
• When low power consumption is required

Who Should Get an Angle Grinder?

One should consider the angle grinder as their ideal choice of cutting tool because two or more of the following factors are important to you or your project:

• When heavy-duty tooling is required for cutting a range of material thickness
• If you need versatility by being able to complete a range of tasks with the same tool (eg cutting and polishing)
• You need a tool that is long-lasting and can withstand regular heavy usage.

Closing Thoughts

The Angle Grinder and the cut-off tool are two very different types of tooling despite some similarities. When considering buying or making use of grinders or cut-off tools for specific jobs, take the time to consider the discussed factors to achieve a successful, safe and productive purchase.