Millwright Level 1 Practice Exam

Why are parallels used under a workpiece during plunge cutting?

1. To improve the aesthetic finish

2. To minimize wear on the cutting tool

3. To prevent cutting into the table

4. For better clamping of the workpiece

The correct answer is: To prevent cutting into the table

Parallels are employed under a workpiece during plunge cutting primarily to prevent cutting into the table. This practice serves several crucial purposes in machining operations. By elevating the workpiece, the parallels create a protective barrier between the cutting tool and the table surface, safeguarding the table from damage that could occur if the cutting tool extends too deep. Using parallels also helps to facilitate better chip removal, as the gaps created allow for more effective evacuation of metal chips produced during the cutting process. Additionally, this setup can contribute to more consistent cutting depth throughout the machining operation, further enhancing the quality of the finished workpiece. When considering the other context of the options, while improving aesthetic finish, minimizing wear on the cutting tool, and enhancing workpiece clamping might seem beneficial, they are not the primary functions of using parallels in plunge cutting. The main aim is to protect the equipment and maintain operational integrity by preventing the cutting tool from incising the table surface.