PRECISION INSTRUMENTS EXPLAINED MICROMETERS CALIPERS GAGE BLOCKS

.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 .001 TENTHS THOUSANDS HUNDREDS

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

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

Reading a Micrometer Observe the greatest 0.100-inch division on the barrel scale. Observe the number of 0.025-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.

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

Observe the number of 0. 025-inch divisions between the 0 Observe the number of 0.025-inch divisions between the 0.300-inch mark and the thimble. (two x 0.025” = 0.050”) 1 2 3 10 5

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” +

TYPES OF CALIPERS VENIER DIAL DIGITAL

OUTSIDE MEASURING JAWS BAR SCALE PARTS OF A CALIPER INSIDE MEASUREING JAWS DIAL .001 DEPTH GAGE OUTSIDE MEASURING JAWS BAR SCALE

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

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

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”

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”

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”

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

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

RINGING TWO BLOCKS TOGETHER SO THEY ATTACH

GAGE BLOCKS RUNG TOGETHER TO GIVE AN ACCURATE SIZE