Understanding Concrete Saws
Concrete saws are your go-to tools to cut, shape, remove and joint the many types of concrete construction you do every day. Like other tools of the trade in your job boxes, these workhorses have undergone important updates in the last few years.
Even though these tools have realized innovations in design, performance, and safety, the basics for selecting the right tool remains the same. Concrete saws fall into several basic configurations. Each is designed for specific cutting actions and orientation of the saw blade to the concrete surface. Let’s look at how to choose the right equipment for cutting and removing concrete.
Even though these tools have realized innovations in design, performance, and safety, the basics for selecting the right tool remains the same. Concrete saws fall into several basic configurations. Each is designed for specific cutting actions and orientation of the saw blade to the concrete surface. Let’s look at how to choose the right equipment for cutting and removing concrete.
Common types of concrete saws
Cut-off Saws
The most common cutting tools are cut-off saws, also referred to as power cutters or hot saws. These handheld tools are very portable and can cut on all types of work areas. The 2 and 4-stroke models are powered by a gas engine. Other options are battery power, electric, and high-frequency electric. Cut-off saws are commonly used in field work as their compact design allows for working in limited access areas with ease. They are also useful to make end cuts on rebar and concrete pipe.
The most common cutting tools are cut-off saws, also referred to as power cutters or hot saws. These handheld tools are very portable and can cut on all types of work areas. The 2 and 4-stroke models are powered by a gas engine. Other options are battery power, electric, and high-frequency electric. Cut-off saws are commonly used in field work as their compact design allows for working in limited access areas with ease. They are also useful to make end cuts on rebar and concrete pipe.
Ring Saws
Operators use ring saws, another type of power cutter, to make deep cuts in pavements, curbs, walls, and floors. These specialized tools use a drive mechanism that spins the outside of the blade (or ring) to add significant cutting depth. The 2-stroke models are powered by a gas engine. Other options are high-frequency electric and hydraulic. A similar style of saw includes a design for step cutting for very deep cuts without overcutting at corners.
Operators use ring saws, another type of power cutter, to make deep cuts in pavements, curbs, walls, and floors. These specialized tools use a drive mechanism that spins the outside of the blade (or ring) to add significant cutting depth. The 2-stroke models are powered by a gas engine. Other options are high-frequency electric and hydraulic. A similar style of saw includes a design for step cutting for very deep cuts without overcutting at corners.
Chainsaws
Concrete chainsaws have bars, on which a diamond-impregnated chain travels, powered by a gas, hydraulic, or high-frequency electric motor. These tools are also useful for end cuts, but their real value is to make entry cuts into walls because they leave no overcut.
Recent research has found that chainsaws are the best choice for cutting pipe below grade, because they expose the operator to less kickback than a circular blade saw. These saws can also be adapted with abrasive grit chains to cut cast iron pipe.
Concrete chainsaws have bars, on which a diamond-impregnated chain travels, powered by a gas, hydraulic, or high-frequency electric motor. These tools are also useful for end cuts, but their real value is to make entry cuts into walls because they leave no overcut.
Recent research has found that chainsaws are the best choice for cutting pipe below grade, because they expose the operator to less kickback than a circular blade saw. These saws can also be adapted with abrasive grit chains to cut cast iron pipe.
Walk-Behind Saws
Walk-behind saws, also referred to as floor saws or flat saws, are circular blade saws mounted on a frame, that are designed for a downward cut into a slab. These assemblies come in a wide range of styles and engine sizes to match your project needs, from small push saws to self-propelled saws and even ride-on models for highway work. There are two basic styles of floor saws to choose from, depending on your project. The first type of floor saws are designed to cut hardened concrete either for tear out and repair or to cut deep control joints in fresh concrete.
Walk-behind saws, also referred to as floor saws or flat saws, are circular blade saws mounted on a frame, that are designed for a downward cut into a slab. These assemblies come in a wide range of styles and engine sizes to match your project needs, from small push saws to self-propelled saws and even ride-on models for highway work. There are two basic styles of floor saws to choose from, depending on your project. The first type of floor saws are designed to cut hardened concrete either for tear out and repair or to cut deep control joints in fresh concrete.
Early Entry Saws
A second type of floor saw is specifically designed to cut control joints in freshly-placed (green) concrete. These saws use small diameter blades specifically designed for joint cutting and typically use guards to prevent spalling.
Saw cuts leave thinner contraction joints, and thus, are easier to fill. And saw cuts leave a squarer joint that reduces any elevation levels between the concrete panels. Some early entry saws can also be fitted with decorative blades that can cut beveled or radiused joints.
The real advantage to these saws is concrete crack control. Ultra Early Entry™ saws allow contractors to cut control joints before stress fractures begin to form in the concrete and direct any cracking to the joint. This process is often specified by architects or engineers, and particularly in critical applications and super-flat floors. These saws can be used as soon as the concrete is hard enough to walk on, which also increases production and eliminates the need to come back the next day.
A second type of floor saw is specifically designed to cut control joints in freshly-placed (green) concrete. These saws use small diameter blades specifically designed for joint cutting and typically use guards to prevent spalling.
Saw cuts leave thinner contraction joints, and thus, are easier to fill. And saw cuts leave a squarer joint that reduces any elevation levels between the concrete panels. Some early entry saws can also be fitted with decorative blades that can cut beveled or radiused joints.
The real advantage to these saws is concrete crack control. Ultra Early Entry™ saws allow contractors to cut control joints before stress fractures begin to form in the concrete and direct any cracking to the joint. This process is often specified by architects or engineers, and particularly in critical applications and super-flat floors. These saws can be used as soon as the concrete is hard enough to walk on, which also increases production and eliminates the need to come back the next day.
Wall Saws
Wall saws are assemblies that position circular saw blades to cut into the vertical or near vertical faces of structures. They are most commonly used to cut doors, windows and ventilation ducts into concrete and masonry walls.
The frames are anchored into the face they are to penetrate. Operators direct the sawing action using hydraulics or cables leaving a clean, precise, and square cut.
Wall saws are assemblies that position circular saw blades to cut into the vertical or near vertical faces of structures. They are most commonly used to cut doors, windows and ventilation ducts into concrete and masonry walls.
The frames are anchored into the face they are to penetrate. Operators direct the sawing action using hydraulics or cables leaving a clean, precise, and square cut.
Wire Saws
Wire saws are demolition tools used to cut sections out of large massive concrete structures such as piers, foundation walls, and footings for removal. Instead of blades, wire saws are assemblies that combine pulleys mounted on a frame and even the structure itself to direct diamond-laced cables along a cutting path. Since the sawing action is more grinding than chipping, the technique minimizes vibration. The final cut surface is smooth and often free from any damage.
Wire saws are demolition tools used to cut sections out of large massive concrete structures such as piers, foundation walls, and footings for removal. Instead of blades, wire saws are assemblies that combine pulleys mounted on a frame and even the structure itself to direct diamond-laced cables along a cutting path. Since the sawing action is more grinding than chipping, the technique minimizes vibration. The final cut surface is smooth and often free from any damage.
Factors When Selecting a Concrete Saw
You should match your investment in concrete saws to the type of work your crews commonly perform. Your decision should be based on three categories – saw cut orientation, depth of cut, and scope of project.Floor saws enable you to make straight line cuts into slabs, floors, and pavements. Your options for types of downward cutting tools include: early entry saws to craft control joints in fresh concrete, walk-behind saws to cut hardened concrete, and cleanout saws to chase cracks prior to repair and to clean out sealant from joints.
For cuts into vertical walls, you have three options. Concrete chainsaws enable you to cut square openings in walls for windows or doors. For larger projects, contractors often opt for either wall saws or wire saws that accurately slice through thick concrete elements leaving clean edges.
For those in-between types of projects, you have two choices. You can use handheld cut-off saws to slice off projections and create openings on curbs and gutters. Some cut-off saws can even be used to remove sections of pavement with the proper blade. If you do a lot of trench work, the concrete chainsaw is a must as it provides a safety factor when cutting embedded pipes.
Methods of Dust Containment
Concrete sawing generates dust as the blade passes through the slab, block, or wall. To create a safe and efficient operation, you must opt for a containment system that allows the job to be completed quickly, while containing any fugitive dust.Dry cutting describes the method that allows the blade to make its entry in the concrete without water. Shrouds that are positioned at the cutting point direct the light chips and silica dust into a dust collector through a vacuum.
Wet sawing uses water that is sprayed just before the contact point to help contain dust emissions. The water also helps to lubricate and cool saw blades. When sawing is completed, you need to collect the slurry that contains the cuttings and dust for disposal.
Check out our page on Sawing Safety to learn more.
Selecting the Right Concrete Saw Blade
Matching the right concrete saw blade to the task at hand is often the difference in making money or not. Blades range in rim styles and cutting materials.Start by looking at the concrete itself. First determine if you are cutting fresh (green) concrete or hardened concrete.
The next choice is often which type of saw you will be using for cutting. It’s important to know that dry cut blades can be used when wet cutting. But wet cut blades should never be used to dry cut.
Cutting depth is also an important consideration. To be ready for all field conditions, saw types, and cutting positions, have a wide array of blades on hand. Check how deep of a cut you want every time. All saw blade manufacturers list the maximum cutting depth on the package.
And the final decision factor is performance versus blade price. For small jobs or occasional cuts, a lower priced, multi-application blade is your best choice. For larger jobs and more regular use, you should invest in blades that last longer and cut faster.