Angle Grinder Concrete – How to Grind Concrete With An Angle Grinder?

A professional using an angle grinder
A professional using an angle grinder

It’s not uncommon for power tools to have multiple uses, but the versatility of an angle grinder surprises even the most experienced users out there. You can use grinders for sanding, sharpening, polishing, cutting metal, and handling different projects.

Would you like to learn how to grind Concrete with an angle grinder? The truth is that smoothing rough Concrete with this tool is more interesting and easier than people thought. Here is what you need to know about these tools and how to use them for grinding concrete floors!

Table of Contents

1. Can I Use an Angle Grinder to Level Concrete?

Do you have an unlevel concrete surface, and would you like to resolve that problem? The good news is that a concrete angle grinder can smoothen, level, and polish these surfaces.

1.1. Why You Should Use an Angle Grinder for Smoothing Concrete?

The short answer is yes, but allow us to offer a detailed explanation. So, the main reason you should use this tool is that it’s portable and compact. Therefore, it will be easy to hold a concrete angle grinder in your hands and move it around.

You’ll also benefit from the grinder’s versatility. Why would you buy multiple tools that you only need occasionally? Instead, an angle grinding tool has multiple uses. These include cutting metal, bricks, Concrete, plastic, and other materials. So, the potential of your grinder only depends on the blade you use. 

1.2. What Projects Are Suitable for an Angle Grinder?

The best angle grinder concrete tool is the one that fits your needs the most. While the most common size is around four inches, you’ll also find bigger tools on the market. 

Angle grinders are affordable tools, although their price might vary. If you plan on using the unit frequently, it could be wise to pick a more powerful motor. Therefore, look for a motor with a minimum strength of 5-9 amps. 

Here is an overview of projects suitable for an angle grinder.

1.2.1. Cut Tile, Stone, and Concrete

Apart from concrete grinding, it’s possible to cut this material and handle cutting stone and tile applications. If you can’t use tile cutters because the area is hard to reach, cutting Concrete with an angle grinder becomes a viable option.

Here are the steps for handling this task:

  1. Start by outlining the cut on both tile’s sides. Furthermore, use clamps to tighten the tile. 
  2. Begin cutting from the backside. You want to aim for straight and crisp corners.
  3. It’s smart to use a dry-cut diamond blade for this project.

1.2.2. Restore Cutting Edges

If you want to restore cutting edges, the best thing to do is to use a grinding wheel. So, you can use this option to grind lawnmower blades, hatchets, axes, etc. 

Check out these tips to optimize the process:

  1. Always connect the blade to a vise, and then use clamps to attach it to the workspace. Use the guard to ensure the sparks go opposite from you.
  2. Now, align the blade and the grinding wheel. Activate the tool and use steady moves and minimal pressure.

1.2.3. Cutting Out Old Mortar

Using a hammer and chisel for these projects is tricky, so grinding can be a smart alternative. Now, here are the steps to follow for cutting out old mortar:

  1. Use a tuckpointing wheel for these projects. 
  2. Make several passes to clear the joint, but stay somewhat away from the brick because you don’t want to risk any damage.

1.2.4. Cut Rods, Bars, and Bolts

Would you like to cut a metal bolt or rod? If the answer is yes, these are the steps to follow:

  1. A metal-cutting blade is mandatory for these projects, so make sure to acquire a suitable one.
  2. Mount the cut-off wheel and hold the tool safely. 
  3. Get the tool close to the metal without applying too much pressure. Dropping the wheel should do most of the work as soon as it touches the surface.

1.2.5. Metal Cleaning

Cleaning metal structures with an angle grinder

Cleaning metal structures with an angle grinder

Source: Cleaning metal structures with an angle grinder

If you have a wire wheel or wire cup brush, it’s possible to clean metal with an angle grinder. Here is how to do that:

  1. You can use clamps to secure the workpiece. 
  2. The brush should always spin in the opposite direction and not into the edge. So, ensure you position it properly since you want to avoid kickbacks.
  3. It’s possible to use a wire wheel to remove paint, too, especially since they fit into tight areas.

2. Pick the Right Diamonds

Selecting the right diamonds is a crucial consideration for angle-grinding projects. That’s why the experts advise taking the time to understand the advantages of various styles and bonds. The primary factor is that you don’t want the diamonds to ruin the floor beyond fixing, especially if you plan to polish it.

It’s smart to try a particular diamond on that type of Concrete. Therefore, test and confirm you picked the right diamond if you have an option. You can also talk to the manufacturer to help you make the right choice. Once you find the ideal option, the results will exceed your expectations.

3. How to Grind Concrete with an Angle Grinder

Are you ready to discover the details of grinding concrete smoothly and ensuring an optimal surface? Here is a simple video that shows concrete grinding. You can find a comprehensive overview of the entire project below.

3.1. What Tools Do We Need?

Before you start grinding, it’s vital to prepare the necessary tools. 

Here is a list of everything that you’ll need to grind a concrete surface:

  • An angle grinder – the general idea is that it should have a blade of 4-7 inches in diameter. You might also need a dust shroud, and don’t forget the diamond polishing pads or similar alternatives.
  • Safety equipment – wear proper clothes, and put on a mask and goggles. Kneepads could also be useful when working on the floors.
  • Cleaning supplies – depending on your needs, you could use a vacuum, mop, or broom.

3.2. Steps to Grinding Concrete Successfully

Angle grinder scoring concrete

Angle grinder scoring concrete

Now that you have everything ready, it’s time to move to the concrete grinding process. Let’s use the garage floor as an example because it’s an excellent testing area before you proceed to more sensitive ones.

3.2.1. Clean the Surface First

The first thing to do is to clean the floor. Therefore, use a broom to clean it and remove any bumps from gums, grease, or similar stains. However, consider vacuuming it or even using a pressure washer if it’s necessary. After the cleaning, you shouldn’t have any residue where the grinder might get stuck.

3.2.2. Get the Angle Grinder Ready

It’s much easier to divide the floor into sections because you’ll have more options to move around and better control of the work done. Additionally, if you want to minimize dust problems, it’s smart to use a dust shroud for the project.

Now it’s time to mount the wheel on the tool. Make sure not to connect your grinder to the electricity socket yet. Therefore, check it’s powered off and mount a diamond polishing or an alternative pad. Finally, wear safety equipment, such as earplugs, gloves, masks, and kneepads. 

3.2.3. Start Grinding!

The time has come to smooth the garage floor by working with your angle grinder. Also, if you have problems reaching corners, it might be smart to use a smaller tool for those sections. 

According to experts, you can divide the floor into sections and start by smoothing the edges first. That’s a matter of preference, so find the way you consider most fitting. If you move from the perimeter inwards, making circular moves with your grinder might be the fastest way to smooth Concrete.

3.2.4. Deal with any Imperfections

Once you finish the grinding process, it’s time to check the results of your work. Therefore, start checking the floor and try to find any imperfections. If you identify an area where the results aren’t up to standards, grind that section again. 

However, before you do that, remove the dust shroud from the tool. That way, the grinder will have better contact with the floor. Finally, the only remaining thing is to mop or vacuum the floor to remove any dust residue.

4. Stay Safe While Smoothing Concrete

Stay safe while using an angle grinder

Stay safe while using an angle grinder.

Apart from ensuring a smooth concrete floor, your primary requirement for angle grinder projects should be staying safe. These are power tools, so caution is necessary if you don’t want to risk injuries and other problems.

Did you know that an average grinder runs at 10,000 RPMs? That’s why you should follow these steps to stay safe:

  • Always wear protective equipment, such as gloves, glasses, and a mask.
  • Never change wheels without checking that you unplugged the grinder. That’s risky because you could accidentally activate the tool, which leads to injuries.
  • Keep the tool with both hands, but always have a firm grip on the handle.
  • Test a new wheel before using it on a concrete surface. That way, you’ll ensure there aren’t any defects.
  • Ensure the debris goes down to reduce the risk of entering your eyes.
  • Never work when other people are around, especially when they don’t have protective equipment.
  • Make sure there aren’t any flammable materials that could get in touch with the sparks.

5. Are grinders the Best Tools for Grinding Concrete?

A grinder at a construction site

A grinder at a construction site

Grinding Concrete with an angle grinder is fairly simple, so even beginners will master the project quickly. However, it would be best to consider some factors that could affect the process. 

5.1. Size

The first consideration is the grinder’s size. Furthermore, the blade size you want to focus on should have a diameter of four to seven inches. However, the problem with these blades is that they aren’t big. You’ll need patience when smoothing rough concrete surfaces, especially with large areas. If that’s the case, don’t hesitate to consider a floor grinder as an alternative.

5.2. Comfort

An angle grinder is a small tool, and you’ll need to move it around. Therefore, using it for grinding floors will require going down on your knees, which can be uncomfortable. Knee pads are a convenient option to make yourself more comfortable, but it can still be unpleasant to smooth large concrete surfaces.

5.3. Efficiency

Once again, we circle back to the small size of an angle grinder. It implies you’ll need plenty of time to smooth a large surface, which doesn’t make this tool very efficient. 

Additionally, it’s worth noting that you might need a wet attachment for a grinding machine. That will improve the cooling down process and ensure the blades don’t head and wear down quickly during use.


Angle grinders can be the perfect option for smoothing concrete surfaces, especially at home. Therefore, DIY enthusiasts and individuals who need it for modest-sized areas will find these tools convenient. Always remember that the project’s success depends on the blade’s suitability and quality.

If you need high-quality blades and other products for power tools, don’t hesitate to contact NCCutiingTools. We gather a team of experts that can help with customized orders and deliver large product batches quickly. Feel free to get in touch if you have any questions or requirements related to power tools and blades!

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