Complete Guide to Cutting Concrete with Angle Grinder

In a developing world like today, where building skyscrapers are every day’s hot topic and building houses for the growing population is a daily activity, cutting concrete slabs, floors, block, and walls are typical there. You will find various options to cut concrete, but cutting concrete with angle grinder is always more convenient for small jobs. Alongside cutting reinforced concrete with angle grinder, cutting tiles, and bricks are also allowable with an angle grinder, as it is a versatile tool.

We already have seen that electricians use angle grinders to make square holes on the wall for electrical outlets. Angle grinders make very sharp and straight cuts in concrete. So, cutting concrete with an angle grinder is a proven task that can be seen worldwide.

If you are reading this article from Electric Counselor, you don’t need to look further into any article mentioning ‘angle grinders and concrete.’ Here we will discuss everything about cutting concrete with angle grinder. Such as everything about concrete cutting blade for angle grinder, cutting reinforced concrete with angle grinder, advantages of using water with angle grinder, cutting concrete footings and cutting concrete slab, etc. An enormous list! Huh? Now, let’s dive into it together.

The Best Concrete Cutting Blade For Angle Grinder

As mentioned before, you will find different options available for cutting concrete. But among all of them, cutting concrete with angle grinders is the most practical and budget-friendly method for DIYers. To cut the concrete slab, concrete blocks, etc. with an angle grinder, you will have to choose the suitable concrete cutting blades for the angle grinder.

Check angle Grinder price

‘Diamond cutting blades’ is the answer you might be looking for. Diamond blades are the best fit for dry and wet concrete cutting. Some facts make a diamond cutting blade the best fit for cutting concrete –

• A synthetic diamond rim around the edge of this blade surrounds an engineered steel core.
• There are ventilation grooves in the blade. These grooves help to cool the blade and keep concrete dust away from the diamond rim.

Concrete Cutting Blade Size

• With a 4.5-inch angle grinder, you can go deep up to 1-1.5 inches.
• With a 9-inch angle grinder, you can go deep up to 3-3.5 inches.

There are various options for a 4.5-inch angle grinder, which can make the task easier for you to cut through concrete up to 1-1.5 inches. There is a rich review article about the best angle grinder for different types of works; you can have a look.

If you have more than 1.5 inches deep to cut through, you can choose a 7-inch or 9-inch angle grinder as they offer more ‘amp motor’ than a 4.5-inch angle grinder.

Right Angle Grinder Diamond Blades

So far, we have discussed the best concrete cutting blade for angle grinders and concrete cutting blade size. We have mentioned that diamond concrete cutting blades are the best fit for cutting concrete with an angle grinder. But there is still a term waiting to be enlightened, that is between the dry type and wet type which one you should choose and why. Dry concrete blades are good as you can use them with or without water. But a wet blade is not recommended to use without water. Since there is no wet cutting angle grinder, using water with an angle grinder is never easy.

So, you have to go for dry-cutting angle grinder diamond blades. You will find three types of these blades. Let’s have a brief discussion.

• Segmented rim angle grinder concrete blades 

  Are you looking for diamond-angle grinder blades to cut concrete? Segmented rim angle grinder concrete blades are the suitable choice for your task. These blades are the best choice available if you can’t choose water to use because the segmented rim of these blades doesn’t allow dust to accumulate and let the airflow cool down the blade. These segmented diamond blades are used to cut bricks, reinforced concrete, concrete pavers, and limestone.
  

• Turbo rim angle grinder diamond blades

  This type of blade helps the operator cut through concrete, brick, and limestone. The specialty of these blades is they can conduct a faster cut speed, be it dry or wet. These diamond blades contain a turbo rim that lets air flow to cool the disc. Also, there are small holes on the turbo rim, which provide extra cooling facilities. Besides, the turbo rim doesn’t allow you to worry about the dust and debris as they push out those dust and debris outside.
  

• Continuous rim angle grinder diamond blades

  Continuous rim diamond blades don’t contain extra cooling methods like segmented and turbo rim blades. So, these blades are preferred for wet cutting. Marble, granite, ceramic, and porcelain tiles are the materials to cut by a continuous rim diamond blade. It’s not wise to cut concrete by continuous rim angle grinder diamond blades.

Cutting Concrete with an Angle Grinder

Mark your cutline

Using a tape measure and pencil, outline the cut you will make on the concrete block. Draw a straight line across the surface of the block using a pencil and carpenter’s square as a guide. The measurement marks are the point from where you have to start.

Safety first

Wear safety glasses, a dust mask, and leather work gloves. When cutting concrete blocks, angle grinders produce a large amount of dust and dirt in addition to the cut.

Dive into the operation

Put the angle grinder into operation. Hold the cover upwards while holding the angle grinder with the blade facing outwards. Whenever it makes a cut, the blade throws debris back to the handle where the operator stands. The disc will roll the sander away from the user if the angle grinder falls or gets stuck in the cut. This provides protection to the user.

Creating grooves

Using the blade of an angle grinder, create grooves on the surface of the concrete block according to the pencil marks. Repeat this process until you have a 1/8 inch deep groove, moving the blade back and forth across the pencil line. Do this action on each of the pencil lines.

Continue the cutting

Using an angle grinder, carefully cut through the concrete block and observe the marks. When cutting straight lines across the entire face of the block, start by cutting both outer edges of the block. Only then should you cut the center of the line. If you want to cut a hole in the center of the concrete block, you need to ensure the angle grinder blade goes through the center of each mark. Once the blade has passed through the center of the scoring marks, you should move it to the four corners of the hole.

Complete your task

To start, you need to turn the concrete block over. On the opposite side of the concrete block, complete the corner cuts and use an angle grinder to remove any excess concrete that was created during the cutting process. The viewing surface of the concrete block should be trimmed from the reverse side to protect it.

Cutting Concrete Slab / Cutting Reinforced Concrete

Cutting concrete slabs or cutting concrete that is reinforced with steel is never easy and not a job for amateurs. For these kinds of jobs, diamond-cutting blades are the priority choice. Make sure that you choose a new one. Because the steel will make the diamond wear down faster than the concretes.

There are some cautions to follow while cutting reinforced concrete or concrete slab. Make sure you are a professional. Because concretes that are reinforced with steel are extremely hard to cut through. This needs extra force and experience to handle. Never try this on your own if you don’t have enough experience to implement it in your work.

Make sure you are not cutting the conduits or any other utilities.

Cutting Concrete Blocks with Angle Grinder

Cutting concrete blocks is a lot easier than cutting concrete slabs. But, no work can be done properly without a suitable plan. To make a proper cutting, you must first mark where you want to cut.

Choosing the dry-cutting option for cutting concrete blocks with an angle grinder will be wise as it is safer and doesn’t create the problems that water does.

Cutting Concrete Pavers with Angle Grinder

It takes several cuts through the concrete while cutting concrete pavers with an angle grinder. After making a cut a few inches deep, you chip or tap out any loose concrete you want to remove, then continue cutting into the tile until you reach the end.

Questions to ask before Cutting Concrete with Angle Grinder

When you are going for cutting concrete with angle grinder, there are some questions to ask yourself. Those questions will help you get your project done correctly and ensure your safety. So, look at the questions below suggested by Electric Counselor.

Is your grip okay?

Before using the angle grinder, you should check the handle and weight to ensure you won’t have any problems managing it. By examining its two handles, you should ensure you can comfortably hold the grinder with the hand you use most. Most grinders have two handles to help keep the tool steady. Be aware that you will need to apply some pressure to move the disc through the concrete, which will cause the tool to feel heavier than it is due to vibration.

Have you prepared your work area?

To ensure a clean workspace and no objects that can harm you and your project later, clean your workspace and make sure you have only the necessary tools besides you. In addition to removing any obstacles that could cause tripping, you should also check that the appliance’s power cord is always behind it, where it is safe to avoid getting into the blade’s path. If your workplace is an enclosed space, you must ensure that it has adequate ventilation.

Are you fully prepared with the safety precautions?

The angle grinder guard will help you from debris and sparks that an angle grinder creates while in operation. Also, there are more personal safety precautions that you have to follow to ensure your complete safety. For example, wearing loose clothes is a bad idea; you should use gloves to protect your hands and improve your grip. During the cutting process, small pieces of concrete can come loose and fly away, creating a potentially dangerous situation. Wear goggles or safety glasses to prevent dust or other particles from entering your eyes. To reduce the chance of inhaling concrete dust, it is recommended to wear a face mask.

Have you marked your cutline?

We have mentioned before that you cannot complete any project correctly without proper planning. So, it is essential to plan appropriately. When you are about to cut any material with an angle grinder, you need to be sure where you will cut and have a clear idea about your starting point and ending point. So, grab a straight edge and a pencil to mark the location of the line you want to cut. This will ensure that the cut you make will be accurate. At this point, you should carefully gouge along the pencil line with a hammer and chisel, making sure the resulting groove is deep enough to hold the blade in place. Depending on the thickness of the concrete, it should take no more than three blows to break through the entire line, and it should be completed successfully. Carrying out this procedure will ensure that you only cut in the desired places, and there is no risk of the blade slipping on the surface.

Are you correctly cutting concrete with angle grinder?

Use both hands while cutting concrete with angle grinder. Let the angle grinder reach its full speed. You will feel a pressure change when you touch the rotating blade with concrete. Get yourself ready for that pressure change. 

The angle grinders were initially designed for angle grinding of metal welds. But day by day, people found it a versatile tool that can be used in many types of projects. Cutting concrete with angle grinder is one of those tasks a grinder can do very smoothly.

The tools have blades that range from 412 inches to 9 inches. The 412-inch and 5-inch models can reach 11,000 rpm but have low torque. Best for grinding concrete stumps. Some manufacturers make tools specific to tuckpointing.

Angle grinders improve stamped concrete, engrave, polish, and handcraft decorative concrete.

More extensive models with 7- to 9-inch blades have lower RPM and more torque. The larger models look the same as, the smaller ones but have different uses. These tools can cut joints like a saw and perform angle grinding. Larger sizes can cut more profound and even bricks.

The Rat Tail Angle Grinder has a long, tapered body and a pistol grip. Ryan Anderson, Bosch angle grinder product manager, says the pistol-like handle is more comfortable. Anderson sees the rat tail grinder becoming a transitional tool.

Angle grinders are similar. Angle grinder features are often user preferred.

Switches can be rockers, slides that click and stay on, finger-activated triggers, or paddle switches. Some models have a feature that prevents the switch from sliding across the floor and injuring workers or damaging the floor. Anderson says some jobs require a sander with a paddle switch for safety.

All angle grinders have wheel guards that slide over the rotating wheel to catch the particles. These covers limit the user’s view of the machine and tool. Because of this and the lengthy replacement of the wheel covers, many users remove them, which the manufacturers do not recommend.