Machining is the removal of material from the workpiece using machine processes such as milling, drilling, turning, and grinding. During the machining, the workpiece and the tool of the machine should be in the correct position.
Usually one is moving while the other is stationary. Therefore, we need a mechanism to keep the position of the workpiece and the tool at the right position. As a result, we use jigs and rigs to hold the material or the tool. However, the mechanisms are different, even if the purpose is similar.
The jig is a component that is used to guide the tool, while the fixture is a device that use to hold the workpiece. The best example for a jig is the drill bushings, which supports and guide the position of drill bits. And the best example for a fixture is the vise, which holds the workpiece in position, but doesn’t guide any tools.
JIGs are used in various operations like drilling, reaming tapping, counterboring, and so on. While fixtures are used in processes such as turning, reaming, milling shaping, grinding, boring, and so on.
Differences Between Jigs and Fixtures
Jigs | Fixtures |
Guides the moving tool position | Holds stationary the workpiece |
The operation of the tool depends upon the jig | The operation of the tool does not depend upon fixtures. |
Most jigs cost more than fixtures | Most fixtures are relatively cheaper than jigs |
Jigs have less weight compared to jigs | Fixtures are heavy |
Less ability use for other manufacturing processes | Ability to use other manufacturing processes as well |
Fixed in different places of the machine or outside the machine | Usually fixed in the table or the base |
Precision is higher with Jigs | Precision is comparatively low |
Increase the efficiency of the manufacturing process by saving time on preparation and marking steps | Efficiency is low compared to jigs |
Jigs
The jig is a machine component that guides the moving tool that operates on a stationary workpiece. In other words, the jig directs the cutting tool to the workpiece. There are several types of jigs.
- Template jigs: a solid plate with drilled holes to guide the drill bit
- Plate jigs: clamped template jigs
- Channel jig: the workpiece is clamped inside the jig
- Diameter jigs: To clamp cylinders and guide the drill bit
- Table jig: the entire table is designed to guide tools
- Sandwitch jig: when template jigs are placed both the top and bottom
- Angular plate jig: to clamp the workpiece in an angular position to guide the tool
- Ring jig: to drill holes for circular flanged parts
- Box ring: to guide the drill bit in different angles using the same clamping settings
- Indexing jig: to guide the bits using a reference
Fixture
The fixture is a machine component that supports and holds the workpiece or the tool in a stationary position. There are several types of fixtures.
- Duplex fixtures: when fixture holds two workpieces
- Turning fixtures: to support and hold the workpiece while rotating
- Miling fixtures: to support and hold the workpiece during the milling process
- Broaching fixtures: to support and hold the workpiece during the broaching process
- Boring fixtures: to support and hold the workpiece during the boring process
- Grinding fixtures: to hold and support the workpiece during the grinding process
- Tapping fixtures: to support and hold the workpiece during the tapping
- Welding fixtures: to support and hold the workpiece during the welding process
- Assembly fixtures: to support and hold the workpieces while assembling
Advantages and Disadvantages of Jigs
- The production speed can be improved using Jigs. For example, when drill bushings are used, the production speed is much higher compared to marking the position for each workpiece.
- When it’s compared with fixtures, jigs are light in weight.
- But the biggest disadvantage of jigs is the cost. Usually, jigs cost more than fixtures.
- Better when the process needs to be repeated over and over again
- Less manual interaction is required, so the labor cost is low.
Advantages and Disadvantages of Fixtures
- Jigs are rigid and fixed into a table or a base. So, it can handle more power.
- Jigs can be used even for different manufacturing operations later.
- Compared to most Jigs, most fixtures are less complex.