The document explains how to use a micrometer screw gauge to measure the thickness of objects. It describes clamping the object between the measuring jaws of the micrometer and turning the screw until the reading no longer changes. To calculate the total reading, add the main scale reading and the product of the head scale reading and the least count. It provides examples of using the formula to calculate total readings from sample main and head scale readings.

1. Micrometre Screw gauge
CH-5 Measurements
Modern Metal working by John R Walker

2. •Objectives:
•To learn the procedure of using MICROMETER SCREW
GUAGE.

3. Micrometer: Is a tool designed to measure the
thickness of an object
SCREW GAUGE/ MICRO METER

4. MEASURING USING THE MICROMETER:
1. Keep the object between the measuring jaws.
2. Bring the measuring jaws together by turning
the screw until the object is clamped and the
thickness to be read no longer changes.
3. Take the main reading and the head scale
reading.

5. For micrometer:
Total reading = MSR + (HSR x LC)
MSR = Main Scale Reading
HSR = Head Scale Reading
LC = Least Count
QUESTION 1
MSR = 7 mm
HSR = 0 x 0.01 mm = 0 mm
Total Reading = 7 mm

6. QUESTION 2
• MSR = 8 mm
• HSR = 12 x 0.01 mm = 0.12 mm
• Total Reading = 8.12 mm

7. QUESTION 3
MSR = 8.5mm
HSR = 12*0.01=0.12
Total Reading =8.5+0.12=8.62

8. Answer : 12. 69
QUESTION 4

9. QUESTION 5
Answer : 23.99