Vernier, Dial, and Electronic Digital Calipers
Session 3
Shop Tools and Techniques 2
Used to lock readings into place
Parts of the Vernier Caliper
Manufactured with both 25- and50-division vernier scales
Bar of 25-divisionvernier scale graduatedsame as micrometer
Shop Tools and Techniques 3
Shop Tools and Techniques 4
Measuring a Workpiece• Remove all burrs from workpiece• Clean surface to be measured• Open jaws enough to pass over work• Close jaws against work and lock
right-hand clamp screw• Turn adjusting screw until jaws just
touch work surface• Lock clamp screw on movable jaw• Read measurement
Shop Tools and Techniques 5
Inch Vernier Caliper
Shop Tools and Techniques 6
Inch Vernier Caliper
Shop Tools and Techniques 7
Inch Vernier Caliper
Shop Tools and Techniques 8
Reading the Measurement
A vernier caliper reading of 1.464 in.
1 x 1.000 = 1.000
4 x 0.100 = .400
1 x 0.050 = .050
14 x 0.001 = .014
1.464 in.
Shop Tools and Techniques 9
Metric Vernier Caliper• Parts same as inch vernier• Main scale graduated in millimeters
• Every main division numbered, each 10 mm• Fifty graduations on sliding scale with every
fifth one numbered• 50 graduations occupy same space as 49
graduations on main scale (49 mm)• 1 vernier division = 0.98 mm so difference between
1 main scale division and 1 vernier division = .02 mm
Shop Tools and Techniques 10
Metric Vernier Caliper
Shop Tools and Techniques 11
Metric Vernier Caliper
Shop Tools and Techniques 12
Reading a Metric Vernier• Last numbered division on bar to left of
vernier scale represents number of millimeters multiplied by 10
• Note how many full graduations showing between this numbered division and zero• Multiply number by 1 mm
• Find line on vernier scale that coincides with line on bar and multiply by 0.02 mm
• Add for total reading
Shop Tools and Techniques 13
Shop Tools and Techniques 14
Dial Caliper• Dial indicator, hand attached to pinion,
mounted on sliding jaw• Accurate to within 0.001 inch.• 1 revolution = .100 or .200 in. of travel
Shop Tools and Techniques 15
Dial Caliper
Shop Tools and Techniques 16
Dial Caliper
Making OD
Measurement
Shop Tools and Techniques 17
Dial Caliper
Shop Tools and Techniques 18
Dial Caliper
Shop Tools and Techniques 19
Dial Caliper
Shop Tools and Techniques 20
Dial Caliper
Shop Tools and Techniques 21
Dial Caliper
Left Hand Version
Shop Tools and Techniques 22
Reading Dial Caliper• Read number to left of moveable jaw.
•Reading is 0.500 inch
• Read dial face•Reading is .028
0.500 + 0.028
0.528
Shop Tools and Techniques 23
Reading Dial Caliper
1.300
+ 0.048
1.348
Shop Tools and Techniques 24
Reading Dial Caliper
2.100
+ 0.033
2.133
Shop Tools and Techniques 25
Reading Dial Caliper
54.00
+ 0.34
54.34
Shop Tools and Techniques 26
Reading Dial Caliper
30.00
+0.04
30.04
Shop Tools and Techniques 27
Shop Tools and Techniques 28
Digital Electronic Caliper• Can provide readings to resolution of
.0005 in. or 0.01 mm at touch of button• No rack, pinion or glass scale• Can connect to Statistical Process Control
(SPC) equipment for inspection purposes
Shop Tools and Techniques 29
Digital Electronic Caliper
Shop Tools and Techniques 30
Digital Electronic Caliper
Shop Tools and Techniques 31
Digital Electronic Caliper
Shop Tools and Techniques 32
Dial or Digital Caliper Base Attachments
Shop Tools and Techniques 33
Vernier Depth Gage• Measures depths of holes, slots and recesses• Read same as
standard vernier caliper
Shop Tools and Techniques 34
Vernier Height Gage
• Variety of sizes:• 12-72 in. or 300-1000 mm.
• Accuracy .001 in 0.02 mm)
• Offset scriber• Attachment that permits
setting heights from face of plate
• Depth gage attachment
Shop Tools and Techniques 35
Shop Tools and Techniques 36
Vernier Height Gage
Shop Tools and Techniques 37
Dial Height Gage
Shop Tools and Techniques 38
Digital Height Gage
Shop Tools and Techniques 39
Precision Height Gage• Provides quick and accurate method of setting
any height within range of instrument• Eliminates need for calculating and assembling
gage blocks• Surface plate used as reference surface
• Made from hardened, ground round steel bar• Measuring steps spaced at 1.000-in (25-mm)• Bar raised or lowered by micrometer thimble
graduated by steps .0001 in or 0.002 mm• Can be used for precision inspection and also
connected to statistical process control equipment
Shop Tools and Techniques 40
Precision Height Gage