---
title: "Jigs and fixtures: purpose and differences"
subject: "Workshop Technology"
chapter: 12
key: "semester_2/workshop_technology:jigs-and-fixtures-purpose-differences"
source: https://www.bctengineer.com/q/semester_2/workshop_technology/jigs-and-fixtures-purpose-differences
site: BCT Engineering
---

# Jigs and fixtures: purpose and differences

Workshop Technology · Chapter 12: Jigs and Fixtures for Machine Shops

- Asked in: year not given, 5 marks
- Video: [Difference between Jig and Fixture full detail in hindi](https://www.youtube.com/watch?v=_sbhmIuAcJ8) — AK All Education
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_2/workshop_technology/jigs-and-fixtures-purpose-differences
- Whole chapter: https://www.bctengineer.com/md/semester_2/workshop_technology/chapter-12

## Question

What are jigs and fixtures? State their purposes and advantages. Differentiate between a jig and a fixture with examples.

## Short answer

A jig guides the tool via bushes (e.g., plate jig); a fixture only locates and holds work without guiding (e.g., milling vice). Purposes include repeatable positioning, eliminating marking out, and faster production with improved accuracy. Jigs are light, for drilling; fixtures are heavy, for milling, turning, etc.

## Answer

A **jig** is a work-holding device that holds and locates the work and also guides the cutting tool (through bushes). A **fixture** holds and locates the work and sets the tool position, but does not guide the tool.

#### Purposes and advantages
- Locate and hold the work in the same position every time, so parts are interchangeable.
- Remove the need for marking out, measuring and setting up, saving time.
- Increase the production rate and reduce the cost per piece; allow semi-skilled operators to be used.
- Improve accuracy and repeatability; reduce scrap.
- Provide safe and rigid clamping; allow several tools or parts to be handled at once.
- Make operations on difficult shapes possible.

#### Differences
| Jig | Fixture |
|---|---|
| Guides the tool through bushes | Does not guide the tool; the tool is set with setting blocks and feelers |
| Usually used for drilling, reaming, tapping | Used for milling, turning, grinding, welding, inspection |
| Usually light, and often not clamped to the table | Heavier, and firmly bolted to the machine table |
| The tool position is fixed by the bush, so no tool setting is needed | The tool must be set relative to the fixture using gauge (setting) blocks |
| Examples: plate jig, box jig, template jig | Examples: milling vice, turning fixture, welding fixture |

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is the key difference between a jig and a fixture?
   A. A jig holds the work and guides the tool; a fixture holds the work but does not guide the tool
   B. A fixture guides the tool; a jig does not
   C. Both guide the tool
   D. A jig is always bolted to the machine table
   Answer: A. A jig guides the tool by bushes, whereas a fixture only locates and holds the work and uses setting blocks. (Key point: Jig vs fixture definition)

2. Which pairing is correct?
   A. Jig: milling; fixture: drilling
   B. Jig: welding; fixture: reaming
   C. Jig: drilling, reaming, tapping; fixture: milling, turning, grinding, welding
   D. Both only for drilling
   Answer: C. Jigs are mainly for hole-making operations; fixtures for milling, turning, grinding, welding and inspection. (Key point: Typical operations)

3. Which is an advantage of using jigs and fixtures?
   A. More marking out is needed
   B. Skilled operators are required
   C. Interchangeable parts, less set-up time and lower cost per piece
   D. Production rate falls
   Answer: C. They locate work repeatably, remove marking out and set-up, and allow semi-skilled operators. (Key point: Advantages)

4. Which is an example of a fixture?
   A. Plate jig
   B. Box jig
   C. Template jig
   D. Milling vice
   Answer: D. Plate, box and template are jigs; a milling vice is a fixture. (Key point: Examples)

## Related in Workshop Technology

- [Locating principle and design of a drill jig](https://www.bctengineer.com/question.md?key=semester_2%2Fworkshop_technology%3Ajig-locating-principle-design) — Workshop Technology, chapter 12

## Related in other subjects

- [Jigs and fixtures: purpose and 3-2-1 principle](https://www.bctengineer.com/question.md?key=semester_4%2Fmanufacturing_and_production_processes%3Ajigs-fixtures-purpose-locating-principles) — Manufacturing and Production Processes, chapter 10
- [Drill jig and fixture design considerations](https://www.bctengineer.com/question.md?key=semester_4%2Fmanufacturing_and_production_processes%3Adrill-jig-milling-fixture-design-principles) — Manufacturing and Production Processes, chapter 10