Technical guide
Jigs vs. Fixtures in CNC Machining: What They Are, When to Use Them, and Why It Matters
The key difference, historical context, selection criteria and industry applications.
If you work in CNC machining or partner with a manufacturing supplier, you've probably run into the terms "jig" and "fixture". Many people use them interchangeably, but they're two distinct things with clearly different roles.
At PrintingHub.ro we regularly work on projects where prototypes or functional parts need these accessories to be machined correctly.
What's the essential difference?
Jig
Guides the tool
Fixture
Holds the part
A drilling jig has hardened bushings that guide the bit exactly where it needs to go. A fixture locks the part on the CNC table, leaving the software to manage tool motion.
How do you choose between a jig and a fixture?
- → Repetitive operation with tool guidance? Jig.
- → Part must stay perfectly still for pre-programmed paths? Fixture.
- → High volume, minimum setup? Jigs are the long-term investment.
- → Short runs with varied geometries? Fixtures are more flexible.
3D printing is increasingly used for prototyping jigs and fixtures — fast iterations, low cost, much shorter lead times.