1. PRECISION INSTRUMENTS EXPLAINED
MICROMETERS
CALIPERS
GAGE BLOCKS

2. .001 TENTHS THOUSANDS HUNDREDS
HOW PRECISE DO I NEED TO BE ? WE NEED TO BE ABLE TO ACCURATELY MEASURE PARTS TO 1/1000 OF AN INCH OR AS A DECIMAL
.001
TENTHS THOUSANDS
HUNDREDS

4. MICROMETER PARTS Ratchet Screw Thimble Thimble Scale Barrel
Barrel Scale
Frame
Spindle
Anvil

5. Divisions 0.001” Division 1 2 3 0.025” Division 0.100” Division Barrel
Scale
Thimble
Scale 1 2 3
0.025” Division
0.100” Division

6. Reading a Micrometer
Observe the greatest inch division on the barrel scale.
Observe the number of inch divisions on the barrel scale.
Add the thimble scale reading (0.001-inch division) that coincides with the horizontal line on the barrel scale.

7. Observe the greatest 0.100-inch division on the barrel scale. (three 0.100” = 0.300”)1 2 3 10 5

8. Observe the number of 0. 025-inch divisions between the 0
Observe the number of inch divisions between the inch mark and the thimble. (two x 0.025” = 0.050”) 1 2 3 10 5

9. Add the thimble scale reading that coincides with the horizontal line on the barrel scale. (eight 0.001” = 0.008”) 1 2 3 10 5
Micrometer reading
0.300”
0.050”
0.008”
0.358” +

10. TYPES OF CALIPERS
VENIER
DIAL
DIGITAL

11. OUTSIDE MEASURING JAWS BAR SCALE
PARTS OF A CALIPER
INSIDE MEASUREING JAWS
DIAL DEPTH GAGE
OUTSIDE MEASURING JAWS BAR SCALE

12. Divisions
1.000”
0.100”
0.010”
0.001” 1 10 20 30 40 50 60 70 80 90

13. Reading Calipers Observe the greatest 1.000” division 1.000” 1 90 101 10 20 30 40 50 60 70 80 90
1.000”

14. Observe the greatest 0.100” (0.100” = 0.600”)
1.000”
0.600” 1 10 20 30 40 50 60 70 80 90
0.600”

15. Observe the greatest 0.010” (0.010” = 0.000”)1 10 20 30 40 50 60 70 80 90
1.000”
0.600”
0.000”

16. Observe the greatest 0.001” (0.001” = 0.005”)1 10 20 30 40 50 60 70 80 90
0.005”
1.000”
0.600”
0.000”
0.005” +
1.605”

17. GAGE BLOCKS ARE VERY ACCURATE MEASURING STANDARDS TO 1\1,000,000 IN.

18. FIVE INDIVUAL GAGE BLOCKS FROM SET
Project Lead The Way, Inc.®
Principles of Engineering
Resource Guide

19. RINGING TWO BLOCKS TOGETHER SO THEY ATTACH

20. GAGE BLOCKS RUNG TOGETHER TO GIVE AN ACCURATE SIZE