Why surface plates are used for marking?
| Why surface plates are used for marking?
A. Because it can withstand heavy weight job
B. Because the marking tools can be placed over it
C. Because its surface is too big
D. Because it provides datum surface / base
Please scroll down to see the correct answer and solution guide.
Right Answer is: D
SOLUTION
Explanation:
- Surface plate is used to test the flatness of other surfaces or to provide a truly flat datum surface in marking off work for machining.
- The flat surface provides stability.
- It is also used for inspection of gauges, jigs, and fixtures.
- Surface plates are generally made of good quality cast iron which is stress-relieved to prevent distortion.
- In order to retain its flatness, a surface pate must be treated with extreme care:
- Always clean a surface plate with a soft dry cloth before use and cover it after use.
- Slide heavy objects onto a surface plate rather than lowering them
- Never hammer anything on a surface plate.