Many industrial components rely on precise internal features to fit, engage, and perform as intended. Whether that means transferring torque, maintaining alignment, or creating a reliable connection between parts, the machining process plays an important role in the final result.
One process commonly used to create these features is broaching.
Broaching is a machining method used to produce accurate internal and external profiles efficiently and consistently. It’s often used for applications involving gears, keyways, and splines—features where repeatability and precision can directly impact performance.
In this guide, we’ll break down how broaching works, explore common broaching applications, and look at how broaching compares to keysetting when selecting the right approach for a component.
What Is Broaching?
Broaching is a machining process that removes material using a multi-tooth cutting tool called a broach. Each cutting tooth removes a small amount of material until the final shape is achieved.
Broaching is a type of gear cutting action that is progressive, meaning the first teeth begin the cut, while each tooth that follows removes slightly more material than the last. By the time the broach completes its pass, the finished feature is already formed.
This approach gives broaching a distinct advantage for applications that require consistency and repeatability.
Broaching machining is commonly used when manufacturers need:
- Reliable part-to-part consistency
- Efficient production once tooling is established
- Minimal secondary machining or finishing
The process can be used to create both internal and external features, although internal profiles are among the most common applications.
Because the geometry is built directly into the tool itself, broaching is particularly effective for producing features that need to perform reliably once assembled and in operation.
How the Broaching Process Creates Precision Features
Broaching creates precision by removing material in controlled increments until the final profile is achieved.
The equipment used for this process is called a broaching machine, which applies the force needed to move the broach through the workpiece while helping ensure accurate and repeatable cutting . While machine setups vary by application, the overall process remains consistent:
- Secure and align the workpiece
- Position the broach for the required feature
- Complete the cut in a continuous pass
- Produce a finished profile with minimal additional machining
Because the final geometry is built into the broach itself, the process delivers strong repeatability and consistent results across production runs.
That combination of efficiency and dimensional control is one reason precision broaching remains a common solution for producing industrial gears, keyways, splines, and other critical internal features.
Common Broaching Applications in Industrial Manufacturing
Broaching supports a wide range of industrial applications, but it’s especially common when main components require accurate engagement, controlled motion, or reliable power transmission.
Gear Broaching
So, what is gear broaching?
Gear broaching refers to the use of a broach to create or finish specific gear-related profiles and internal features. Because most types of gears depend on precise geometry to work correctly, even small variations between the teeth can affect performance, efficiency, and wear over time.
Broaching provides a repeatable method to create these profiles while maintaining consistent dimensions across production runs.
Gear broaching is often selected when applications require:
- Accurate profile creation
- Consistent engagement between components
- Reliable repeatability
- Production efficiency for repeat parts
When evaluating gear broaching services, manufacturers are typically balancing precision requirements with production goals to achieve reliable long-term performance.
Keyway Broaching
Keyway broaching is one of the most common broaching applications and plays an important role in power transmission.
Keyways are machined slots that allow a key to connect rotating components—typically a shaft and hub—so torque can transfer between them. Because these features directly affect how components engage, dimensional accuracy matters.
A keyway that is too loose can lead to movement and wear. A keyway that is too tight may create assembly challenges or affect performance.
Broaching provides a practical solution for producing keyways with consistent dimensions and repeatable results.
You’ll commonly find keyway broaching used in:
- Industrial drives
- Couplings and hubs
- Rotating assemblies
- Equipment with shaft-driven systems
For repeat production, the process offers both consistency and efficiency.
Spline Broaching
Spline broaching is used to create profiles with multiple grooves or teeth that engage with a mating component.
Unlike a single keyway, splines distribute load across several contact points, which can help support better alignment and higher torque transmission depending on the application.
Spline profiles are typically used when components need:
- Consistent mechanical engagement
- Improved load distribution
- Reliable alignment
- Repeatable assembly performance
Because splined components depend on close tolerances, the machining process plays an important role in how those parts function once installed.
Broaching vs. Keysetting: What’s the Difference?
Broaching and keysetting are often discussed together because both are used to create internal features, but the processes operate differently. Each one offers different advantages depending on the application.
Broaching uses a dedicated cutting tool with progressively larger teeth to remove gear material and form the final profile.
Keysetting uses a reciprocating cutting action to machine internal features, including keyways.
The best choice for your application depends on several factors, including:
- Production volume
- Component geometry
- Feature dimensions
- Tooling requirements
- Tolerance expectations
Broaching is often selected for repeat production and dedicated profiles, while keysetting can offer flexibility for certain geometries or applications where broaching may not be the ideal fit.
Rather than viewing one process as a replacement for the other, try to think of them as two different solutions for achieving the same goal: producing accurate, functional features that support reliable performance.
When to Consider Professional Broaching and Keysetting Services
Choosing the right machining process isn’t just about creating the required feature—it’s about selecting an approach that supports long-term performance, production efficiency, and consistent quality.
As components become more specialized, factors like geometry, tolerances, production volume, and tooling requirements can all influence whether broaching or keysetting is the better fit.
That’s where working with an experienced manufacturing partner can add value.
At Lawler Gear, broaching and keysetting services are used to produce precise internal features that support reliable fit and function across industrial applications. Rather than treating every project the same, the team evaluates the specific requirements of the component to determine the most effective machining approach.
For manufacturers managing repeat production, replacing worn components, or developing custom gears and other parts, selecting the right process early can help reduce rework and improve consistency throughout production.
Finding the Right Fit for Your Application
Broaching offers an efficient and repeatable way to produce precise internal features, but selecting the right machining process for industrial gears goes beyond simply achieving the final geometry. Production volume, tolerances, feature requirements, and long-term performance all play a role in determining whether broaching or keysetting is the better fit.
That’s why process selection matters just as much as execution.
At Lawler Gear, we work with manufacturers to evaluate application requirements and determine the best approach for producing accurate, reliable internal features. With broaching and keysetting capabilities, our team helps customers match the machining process to the performance demands of the finished component.
If you’re planning a new project or evaluating options for an existing part, contact Lawler Gear today to discuss your application and explore the right solution for your production goals.
