Question

Indexing fixture is used in _______
1. Surface finishing on a milling machine. 
2. Countersink boring on a drilling machine. 
3. Turning operation on a lathe. 
4. Gear cutting operation on a milling machine.

Answer 1

Correct Answer - Option 4 : Gear cutting operation on a milling machine.

Explanation:

• Jigs and fixtures are production tools used to accurately manufacture duplicate and interchangeable parts.
• Jigs and fixtures are specially designed so that large numbers of components can be machined or assembled identically, and to ensure interchangeability of components.

Fixtures

• A fixture is a production tool that locates and holds the work-piece
• It does not guide the cutting tools, but the tools can be positioned before cutting with the help of setting blocks and feeler gauges, etc
• Fixtures of different types are made for milling, turning, grinding, welding, bending, etc
• Types of fixtures are determined mainly by how the tool is used. Because of the increased tool forces, fixtures are built stronger and heavier than jigs.
• The most common type of fixtures are
  • Plate
  • Indexing
  • Angle plate
  • Vice jaw
• Indexing fixtures
  • These fixtures are used for parts that require machining on evenly spaced surfaces, therefore, in a hobbing machine to manufacture the gear teeth, the index plate is fixed on the machine to generate evenly spaced teeth.