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FITTER - CITS

LESSON 20: Jigs And Fixture

Objectives

At the end of this lesson you shall be able to
• define the jigs and fixture
• state the different types and application of jigs and fixture
• state the difference between jig and fixture
Definition Of Jig & Their Applications

Define the jigs
A jig is a type of tool used to control the location and/or motion of another tool. A jig’s primary purpose is to provide
repeatability, accuracy, and interchangeability in the manufacturing of products
Types of jigs
Jigs are essential tools in manufacturing and machining, designed to guide and hold work pieces during various
operations. They come in several types, each tailored to specific tasks. Fixture jigs secure work pieces in a fixed
position for tasks like drilling or welding. Template jigs use templates or patterns for shaping work pieces, often
seen in woodworking.
Template Jig:Template jigs are the most common and basic type of jigs used to produce and machine a small
number of simple parts.

Plate Jigs- Plate jigs are redesigned or upgraded versions of template jigs, as they typically include a method of
fastening to the part that’s.
• Unlike fixtures, jigs both hold and guide the tool.

• Jigs are lighter for easier handling and often do not require clamping.
• Typically used for drilling, reaming, or tapping operations.
Channel Jigs- As their name implies, channel jigs are formed as channels and allow the machining of parts on
three sides, or three surface
• It features a channel-like cross-section.
• The workpiece is fitted within the channel and located using a knob.
• The tool is guided through a drill bush.

Leaf Jigs- Leaf jigs are comprised of a plate jig and a backup plate that provides additional support for thinner
parts that would otherwise bend or distort under tool pressure.
• Includes a hinged leaf or plate for easy loading and unloading of the workpiece.

• Work is located by buttons and clamped using set screws.
• The tool is guided through a drill bush.
Box Jigs- These are used in a similar way to channel jigs but are typically formed as a box or a framework around
the work piece.
• Box-like construction that locates the component using buttons.
• Work is clamped by rotating a cam handle, which also provides location.
• Drill bushes guide the tool.

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