Industrial Design
Fixtures: What are they for?
- IARM Systems
- April 2022
- 8 min read
If we go back to the origins of mass production, the boom in serial manufacturing created a strong need to meet demand while ensuring quality and compliance with international standards. To achieve this, the industry began adopting specialized tools—one of the most important among them: the fixture.
As you know, the specialization and standardization of production processes have only been possible thanks to a wide variety of devices—each serving a specific purpose and, together, enabling consistent, efficient workflows on production lines.
In this article, we’ll explore what fixtures are, their main characteristics, and the technical terms you’re likely to encounter when using them in industrial automation projects.
Ready to dive in? Let’s start by understanding…
What is a fixture?
A fixture is a device designed to hold, locate, and secure one or several components during a manufacturing process. It incorporates mechanical elements, fasteners, or welded components that help reference and align both the parts being processed and the tools being used.
Unlike jigs, fixtures don’t guide the working tools themselves; they simply position and retain the part, while jigs add tool guidance to the operation.
Checking fixture.
As mentioned earlier, quality is fundamental in manufacturing. Checking fixtures are devices designed to verify that a product, part, or assembly complies with all specifications, dimensions, and tolerances defined by the client.
These fixtures are built according to the ideal or acceptable conditions of the finished part, allowing operators or inspectors to confirm whether the product meets required standards.
They can include features for quick verification, bore measurement, flatness or position checks—helping determine whether process or tooling adjustments are needed. This minimizes rework, reduces material waste, and ensures the final product meets the expected quality and reliability levels.
Welding fixture.
A welding fixture holds one or multiple components in precise alignment to ensure correct positioning before joining them through welding processes such as MIG, TIG, stick, or submerged arc.
Because these parts become structural elements of the final product, ensuring their alignment is essential to prevent weak joints, deformation, or failure in the field.
Welding fixtures can range from simple setups with manual clamps and locating pins to semi- or fully automated systems using sensors, pneumatic cylinders, or electric actuators.
These mechanisms ensure that both robotic and manual welders operate under optimal, repeatable conditions—guaranteeing weld quality and production consistency.
Holding fixture.
A holding fixture is used to secure a part or assembly for dimensional verification with a Coordinate Measuring Machine (CMM).
In this process, a Cartesian-type robot equipped with a probe measures key points of the part and compares them to CAD model data.
This ensures that specified tolerances and dimensions are met. Without a proper holding fixture, measurements could vary between tests—leading to inaccurate or misleading results and potentially affecting product quality and supplier reliability.
Holding fixtures include support surfaces and fastening elements to fix the part in a consistent reference position (the “zero” point) defined in the CMM program.
Fixture tool.
The term “tool” is often used generically to describe fixtures that assist with part placement and alignment. In many cases, these tools are integrated into machines or serve as the actual means of performing a specific operation.
Fixture tools not only secure and align components but may also include features that guide cutting, assembly, or machining tools—ensuring accuracy and repeatability throughout production.
Fixture and jig.
The term “jig” originated from machining operations, where templates were used to guide cutting tools and maintain accuracy. A jig controls both the position of the workpiece and the movement of the tool, guaranteeing repeatability and precision.
While a fixture may or may not include a jig, a jig always incorporates a fixture to properly hold the part in place.
Conclusions.
As we’ve seen, fixtures are much more than support tools—they are essential for ensuring optimal production conditions. They can even act as poka-yoke (error-proofing) devices that enhance quality, consistency, and operator specialization while safeguarding process reliability.
Their versatility makes them indispensable in modern manufacturing. Fixtures can be purely mechanical—with manual clamps and bolts—or integrate electrical, pneumatic, or hydraulic elements, depending on the automation level required.
Ultimately, the right fixture determines the precision, safety, and repeatability that define successful industrial production.
