A Sawzall is a reciprocating saw that cuts by rapidly pushing and pulling a straight blade back and forth, thousands of times per minute. The tool converts the steady rotational motion of an electric motor into a fast reciprocating (back-and-forth) movement through an internal crank or scotch-yoke mechanism. This simple principle makes the reciprocating saw one of the most versatile cutting tools in construction, demolition, plumbing, and home repair work. Note that Sawzall is a Milwaukee Electric Tool Company trademark; the general tool category is called a reciprocating saw.
What Is a Sawzall?
Sawzall is a brand name coined by Milwaukee for their popular line of reciprocating saws. Over decades, the term has become genericized in everyday speech, similar to how some people say “Kleenex” for any tissue. However, reciprocating saws as a tool category encompass many brands and models, each with the same fundamental operating principle.
A reciprocating saw is a handheld power tool with a straight, narrow blade that moves in a horizontal line—pushing forward and pulling backward—to cut through materials. Unlike a circular saw that rotates a round blade in a plane, or a band saw that runs a continuous loop, the reciprocating saw’s blade movement is purely linear and can access tight spaces, make curved cuts, and handle irregular surfaces that other saws cannot.
Reciprocating saws are used for demolition work (cutting through nails, pipes, and wooden studs), plumbing and electrical rough-in (cutting holes in drywall and framing), pruning branches, cutting metal and plastic pipes, and any task where you need a saw that can reach into cramped spaces. They are essential tools on construction sites and in tool collections because of their adaptability and raw cutting power.
The Internal Mechanism: Rotary to Reciprocating Motion
At the heart of a reciprocating saw is a simple mechanical challenge: how to transform the constant circular motion of an electric motor into a back-and-forth linear motion. Most reciprocating saws use one of two mechanisms to accomplish this: a crank mechanism or a scotch-yoke mechanism.
In a crank mechanism, the motor shaft is connected to a crank arm—a short rod offset from the center of rotation. As the motor spins, the crank arm traces a circle. The blade is attached to a piston or slider rod that is connected to the end of the crank arm through a connecting rod. As the crank rotates, the connecting rod pushes and pulls the piston back and forth in a linear path. The farther the crank arm is offset, the greater the blade’s stroke length (the total distance it travels forward and backward).
A scotch-yoke mechanism works similarly but with a different geometry. Instead of a connecting rod, the crank arm slides through a slot in the blade’s drive housing. This slot constrains the crank arm to move only along its length, converting the circular motion into pure linear motion. The scotch-yoke design is often more efficient and produces a more uniform blade speed throughout the stroke, but both mechanisms achieve the same goal: rapid reciprocation.
The motor speed (measured in rotations per minute, or RPM) and the crank’s offset determine the blade’s stroke frequency—how many times per second the blade moves back and forth. Most reciprocating saws operate between 2,000 and 3,000 strokes per minute when set to maximum speed, allowing the blade to make many cuts in a single second. Some models include variable speed controls that allow you to slow the blade’s motion for tougher materials or more precision.
How the Blade Action Cuts Materials
The reciprocating saw cuts by the blade’s teeth engaging and tearing through material on both the push stroke (forward) and the pull stroke (backward). Unlike a traditional handsaw, which typically cuts only on the pull stroke, the reciprocating saw’s blade is designed to cut aggressively in both directions, roughly doubling the cutting action per second.
On the push stroke, the blade’s teeth bite into the material and move forward. On the pull stroke, the same teeth pull backward through the material, continuing to cut. This dual-direction cutting is why reciprocating saws are so efficient at ripping through dense materials like wood studs, metal pipes, and composite materials quickly. The rapid blade oscillation also produces significant vibration and noise, which are inherent to the tool’s operation.
The blade’s design—tooth size, spacing, hardness, and thickness—determines what materials it can cut and how effectively. For example, a coarse wood-cutting blade has large, widely-spaced teeth that clear sawdust quickly and are ideal for fast cuts through lumber. A fine metal-cutting blade has smaller, closer-together teeth that make slower, cleaner cuts in steel or aluminum. Using the wrong blade type will result in poor cutting, rapid blade wear, and potential damage to the motor.
Typical Use Cases for a Sawzall
Reciprocating saws excel in demolition because they can cut through wood, nails, drywall, and pipe without hesitation. When dismantling a wall or removing an old frame, the reciprocating saw’s ability to cut through mixed materials (wood, nails, concrete anchors) in one tool makes it indispensable. The blade can reach into tight corners and between studs where other saws cannot fit.
In plumbing and electrical work, reciprocating saws are used to cut holes through framing for rough-in installations. They can cut through copper, PVC, and galvanized pipe with appropriate blade selection. Contractors also use them for pruning thick branches and cutting roots during landscaping work.
Materials that reciprocating saws can cut include wood, drywall, metal (steel, aluminum, copper), PVC plastic, fiberglass, and cast iron, depending on the blade selected. Some heavy-duty reciprocating saws can even cut through thin concrete and masonry with diamond grit blades, though this typically requires models with higher power ratings.
Key Features and Controls
Modern reciprocating saws include several features that affect how they operate and perform. Variable speed control allows the operator to adjust the motor RPM and therefore the blade’s stroke frequency from as low as 500–1,000 strokes per minute up to the maximum 3,000 or more. Slower speeds provide more control and are better for delicate cuts or harder materials, while maximum speed delivers raw cutting power for demolition work.
Orbital action is an optional cutting pattern available on many reciprocating saws. In orbital mode, the blade moves not only forward and backward but also in a slight elliptical or circular motion. This additional movement lifts the blade away from the cut surface on the return stroke, reducing friction and heat buildup, and can increase cutting speed by up to 30 percent for wood cutting. Orbital action is less aggressive than pure reciprocation and can prolong blade life in repetitive cutting tasks.
The blade clamp system secures the blade to the drive mechanism. Most modern reciprocating saws use a quick-change clamp that allows tool-free blade insertion and removal. You simply pull a lever or trigger, slide the blade into the opening, and lock it in place. This design makes it fast and easy to swap blades for different materials without needing a wrench or hex key. Proper blade clamping is essential for safety and performance; a loose blade can break, bind, or cause loss of control.
