How to chisel concrete?

What is a masonry chisel?

How to use a concrete chisel? Before we hammer in and start drilling into the procedures, let’s get to the basics. 

Masonry chisels

How to use a concrete chisel? Before we start drilling into the procedures, let’s get to the basics.

Masonry chisels or cold chisels are used mainly to cut through and shape hard materials, such as various stones and masonry. These are highly effective even on hard concrete without blunting. 

Where to use masonry chisels?

1. Removing excess concrete. Masonry chisels are better at removing excess concrete than if you simply use just a hammer. Cold chisels work with more precision, best for decorative concrete chiseling, and reducing the likelihood of damage and having to redo surfaces.
2. Breaking away concrete runs. Cold chisels allow you to break up concrete/pavement similar to how an ice pick breaks up ice – convenient and controlled. With masonry chisels, you can work at breaking up a corner edge inside a concrete channel, reducing error margins compared to an electric breaker.
3. Creating a channel in concrete. Masonry chisels classify as cold chisels, meaning that they excel at cutting hard materials. If you have some concrete to shape, you can easily hollow out a channel within it by gradually chipping away the excess.

What tools can chisel concrete?

Your way on how to chisel concrete will depend on the scope of your project and the tools available to you.

Dyna drill or rotary hammer

A Dyna drill or rotary hammer uses hydraulic drilling fluid to drive a drill bit or masonry chisel instead of a direct electric motor.

What makes the Dyna drills and other rotary hammers different from other power drills is their ability to ‘pound’ drill bits back and forth as they spin, allowing them to punch through tougher materials like concrete and stone. 

And in this case, they can even be used with a masonry chisel bit in a back and forth motion without rotation.

Steel bar

This refers to a long steel bar that has a chisel tip on one end and a pointed tip on the other. It can be used to break off a lot of dense material very quickly before refining with a smaller masonry chisel.

A specialized steel bar is good for breaking large bits of concrete up using only the weight of the bar and its sharp edge.

Kango hammer

Just like the Dyna drill, a kango hammer is a powerful tool that looks like a miniature jackhammer. In fact, it does exactly the same thing, but on a smaller scale than a jackhammer and with more power than a Dyna drill.

It can break rock, concrete, and masonry and offers more precision and control as opposed to a regular jackhammer.

Where to use a Dyna drill (rotary hammer)?

Use a Dyna drill or any rotary hammer for breaking off medium portions of concrete such as on floors and making grooves or channels in concrete. Set the drill to hammer mode so that it only drives the bit back and forth without any torque.

Of course, you can also drill out holes as either a guide for chiseling corners or to weaken the concrete to make it easier to break.

When to use a steel breaker bar?

Also known as a digging bar, this is a multipurpose steel bar that can be used for several applications from breaking up compact material to levering heavy objects.

It usually has a chisel tip on one end and a spike on the other. Use these for post-hole applications or when needing to loosen or break up large slabs of masonry such as concrete pavements and asphalt road layers.

When to use a Kango hammer?

If you need a very powerful tool to break the largest and hardest concrete or masonry segments, the kango hammer is your best bet. Use this to tear down concrete and masonry walls, slabs, and rock.

Aside from being a breaker, you can also use the kango for some detail-work such as roughly shaping concrete with the help of a small chisel tip.

Manual chiseling vs hammer drilling concrete

Chiseling by hand had always been the traditional way of shaping and breaking concrete. Despite the introduction of power tools on the market that makes the task more manageable, manual chiseling has and will not die out anytime soon. Let’s take a look at why:

Manual hammering concrete

Advantages

• More precision and offers a greater degree of control.
• More suitable for smaller tasks and those that require greater detail.
• A more practical and affordable option.

Disadvantages

• Slower. 
• More tedious.

Hammer drilling concrete

Advantages

• Faster and more convenient.
• More suitable for higher volume work. 
• Better for harder/tougher materials. 

Disadvantages

• Results are a bit rougher and the tools have a higher learning curve.
• More expensive to set up the gear needed.

How to pick a masonry chisels?

Take note that most of these are compatible and designed to function with rotary and similar types of power hammers not only as a hand chisel.

Chisels attached to Dynad drills are also referred to as hammer drill chisel attachments or masonry bits. And the tips are similar to manual cold chisels.

Moil chisels

This rotary hammer drill chisel has a sharp, tapered tip for piercing through concrete, brick, and slab.

These are great for optimum positioning of materials for easier separation. Ideal for clean-up operations and demolition work.

Asphalt cutters

These are specialized chisels that are mainly used for cutting and chipping away asphalt layers. They usually have wider-than-normal blades, with some measuring up to 5”. They look like spatulas and are best used on surfaces with asphalt.

Carbide bushing tool

A distinct masonry chisel almost exclusively used to roughen smooth concrete surfaces. The common flat cutting edge has been replaced with a square, toothed striking one which agitates a finished concrete surface just enough to allow for additional layers and coats for renovation/touch-up projects.

Clay Spade

A chisel designed to work with softer materials such as clay, dirt, and gravel. They look very much like asphalt cutters but are not intended to be used on concrete and similar surfaces.

A great option for gardening, excavation, and other lighter applications.

Flexible chisels

Versatile chisels are adept for medium to heavy-duty applications and can work with a range of light materials from linoleum to vinyl.

These are better at scraping and shaving off material, especially if you don’t want to damage the base material. Best used on flooring and walls.

Tamper

A unique kind of ‘Chisel’ in that it doesn’t really remove material, but is mainly used to either stamp or imprint a particular pattern onto material surfaces or to compact loose material.

Flat chisels

As the name implies, these are chisels with flat cutting edges and are the choice masonry chisels for doing detailed work or when smoothing out and finishing surfaces.

A common SDS hammer drill chisel and best used in tandem with other chisels.

How to pick the right concrete breaker?

But before you find out how to use an SDS chisel to remove mortar from concrete, make sure you know what type of concrete breaker to use.

Rotary hammer (Dyna drill)

Go with a rotary hammer for finer control and variety. These are subtler and more versatile than chipping hammers as they can also be used to drill into both soft and hard materials. And are available in both a corded and cordless version.

Chipping hammer (Kango hammer)

If you’re going for raw power, then a chipping hammer is the better option for chiseling off excess concrete.

Pick this for projects that require mass breaking or chiseling of portions or for demolishing walls and flooring.

What type of hammer to use for cold chisel?

For a cold chisel, you’d use a sledgehammer made of forged steelhead or a machinist’s hammer.

For masonry chisels, a power hammer (rotary) is commonly used. A hammer’s added power has good synergy with the chisel’s natural characteristic to be able to take on harder and tougher materials.

1. Hold the chisel firmly with one hand and a hammer with the other.
2. Place the chisel on the surface you want to break. Angle the tip so that only one of the corners touches the surface.
3. Strike the back of the chisel with the hammer at half swing and follow through with a full swing.
4. Continue until you have dug a hole at a depth you want to break off.
5. Remove the rest of the concrete by repositioning the chisel with the tip parallel to the concrete’s surface. Strike the back of the chisel while alternating between half and full swings until you have your desired result.

Here’s to more hammer types for striking jobs.

How to chisel concrete with a breaker bar?

1. Hold the breaker bar firmly with both arms with the pointed tip facing down and raise it up.
2. Aim at the surface you want to break and drive it down. You may have to repeat this a couple of times until an impact crater has formed.
3. Rotate the bar so that the chisel tip now faces downwards.
4. Lift the bar and strike down repeatedly until it cracks in half or portions of the concrete you want to break apart.
5. Lever the portions of cracked concrete with the pointed tip of your bar and lift them out with the chisel tip.
6. Repeat until you reach your desired results.

How to chisel with concrete breaker?

1. If you’re using a rotary hammer, or kango hammer make sure to set it to hammer-only mode.
2. Attach the appropriate chisel-tip bit for the job. For a cleaner result, start off with a smaller bit to create pilot cuts before stepping up to larger ones.
3. Make sure there is plenty of grease in the joint that connects the breaker bit to the tool to stop it from overheating.
4. Connect your concrete breaker to a power source.
5. Place the tip of the bit on the surface you want to break.
6. Power the breaker on. Remember to only apply appropriate pressure and let the concussive drilling/ hammering do most of the work for you. Pushing too hard on the tool is just unnecessary.
7. Occasionally remove debris from the work area. This can help you see better, prevent binding as well as prolong the life of your bits.
8. Repeat until you reach your desired results.

Safety tips when chiseling concrete blocks

Chiseling and breaking concrete creates safety hazards such as falling debris, flying shrapnel, and lots of dust. Always remember to dress properly and wear safety goggles, work gloves, and a dust mask. You may also want to wear hearing protection when working with concrete breakers as they tend to create noises loud enough to cause hearing damage. Make sure your tools are working properly and in good condition.

Ways to chip concrete without using chisel

Angle grinder

An angle grinder isn’t just used to cut wood and metal. See how and where to use them. With an appropriate concrete-cutting blade, an angle grinder can do wonders if you need to create clean and straight cuts in concrete to make breaking easier.

Concrete cutter

Also known as a concrete saw, this is a specialized tool designed solely for cutting concrete.

They can vary in size, with some even having wheels to make large cuts on concrete slabs.

Conclusion

The best tool for chiseling concrete depends on the scope of your project. Concrete can be found everywhere from the walls and floors of structures to the pavement and pillars that support roadways and bridges. Knowing how to chisel concrete is essential for any DIYer and professional who works with masonry materials as refinement, repair, and restoration are not fully attainable without this knowledge and skill set. Keep your masonry tools in good condition and out of rust.

Structural integrity is important for keeping things together, but in the event that you have the sudden urge to demolish stone, brick, and mortar, then think of this guide as your pocket-manual for breaking various forms of rock-based mediums.

But if you’re into woodcrafts, here’s how you can chisel through woods.