Jig vs Fixture - Differences, Similarities and Design
Difference between Jig and Fixture
The jig tool is a type of machine which helps in guiding the cutting tool. It is used primarily for spacing and locating the drilled holes. The commonly used jig tool is called the drill jig. This tool helps in guiding the drill bit during the creation of holes at required locations. The drill jigs help in increasing the production rate by reducing the time used while using a centre punch, height gauge, scriber, and more.
Whereas, a fixture is a tool that helps in holding the workpiece along the machine bed at the precise location. It helps in reducing the non-productive fixing time, unloading, and loading of the working piece. It does not guide the cutting tool. It only provides a reference to the device or the surface.
Similarities between Jig and Fixture
Fixtures and jigs help in increasing productivity by reducing or eliminating frequent checking, positioning, and individual marking. They also help in reducing the operation time by increasing the depth of cut, feed, and speed due to high clamping rigidity.
Fixtures and jigs allow for the employment of semi-skilled and unskilled machine operators which helps in saving the labor cost. Both the tools provide for easy assembly and reduction in the scrap that further helps in the decrease in unit cost. Users can produce articles in vast quantities with better accuracy and uniform quality.
Advantages of Jig
There are various advantages of using jigs. Some of them are mentioned below but not limited to the followings,
- Reduction in cost while an increase in production.
- It ensures high accuracy of the parts and interchangeability.
- Low variability in the dimensions. Hence, leading to consistent quality and quantity of manufactured products.
- Massive and complex components can be machined easily with them.
Disadvantages of Jig
When you are using jigs, there are a few disadvantages about them that you need to keep in mind from beforehand. For instance, they can use a tremendous amount of material during the operation. Jigs can be bulky at times.
In addition to that, the initial setup time, as well as the cost, is high. Hence, you have to make sure that you have enough amounts of cash as well as time in your hand to spend behind it. Moreover, if you are not buying a high-end jig which features premium quality, you would not be able to work peacefully.
They can wear away quickly within a short period. If you want to use the jig tools for a long time, you have to invest in high-end products.
Advantages of Fixture
The benefits of using fixtures are innumerable as well. Take a look at some of them,
- They eliminate the requirement of setting up the individual work-piece, alignments, positioning, punching, marking out, and measuring, thereby reducing the setup time and the cycle drastically.
- It helps in reducing the number of production defects.
- It also helps in saving labor due to its easy assembly feature. The tool can cater to some extent of automation.
Disadvantages of Fixture
The obstacle that you would face while using a fixture depends on the type of fixture tool you are using. Here we will talk about two commonly used fixture tools and the disadvantages related to them.
For instance, if you are using a fixed position measurement fixture, the reloading, unloading, and loading, of similar parts, is time-consuming. It can also lead to distortion or damage to the parts that might ultimately result in dimensional failures.
Whereas, if you are using a rotational position measurement fixture, the weight of it might bother you. In addition to that, the Y-axis has a larger spacing than the fixed type. This disadvantage is in terms of accommodating the rotation of all the rows.
Types of Jigs and Fixtures
The complexity, model, and quantity of jigs and fixture depends on the work type to be a machine as well as the production scale required. Here is a list of different kinds of jigs and fixtures.
Although there a lot of variety of jigs available for multiple purpose, the following are the main types of jigs used in woodworking:
- Pocket-Hole Jig
- Dowel/Doweling Jig
- Dovetail Jig
- Cabinet Hardware Jig
- Router Jig
- Table Saw Jig
- Tenoning Jig
- Taper Jig
Just like jigs, you can find different kinds of fixtures as well. Some fixture tools are used for particular purposes which others are used for general purposes. There are ten different types of fixture tools, as well. They are mentioned below,
- Assembly fixture
- Welding fixture
- Duplex fixture
- Tapping fixture
- Indexing fixture
- Boring fixture
- Grinding fixture
- Broaching fixture
- Milling fixture
- Turning fixture.
Jig and Fixture Design
The design of fixtures and jigs depends on numerous factors that are analyzed for achieving an optimum output. For making the expected objectives, fixtures and jigs consist of various elements. While designing the fixture tools and jig tools, the mod of clamping and location should be kept in mind. So that the idle time can be reduced to a minimum.
The tool needs to be arranged such that the loading should not take more than a single batch of components; meanwhile, another batch is machined at the same time. The clamping and location influence both the quality and accuracy of a part.
In addition to this, for rough surfaces, there should be adjustable locators. The location pins should also be easily accessible, visible, and tapered to the operator. The manipulative difficulties and safety of the operator should also be given due consideration. It can be achieved by using retractable location pins.
Therefore, it can be easily inferred that both fixtures and jigs can be used for reducing the non-productive time in terms of the mass production process. They can bring huge profits in terms of saving money and labor.
The only difference between these two is, the jig tools are used as a guiding tool. It comes in contact with other devices like the cutting tool. While the fixture does not have any direct contact with any device, it only assures the alignment and position of the workpieces.
