PRECISION MEASURMENTPRECISION MEASURMENT

VocabularyVocabulary1.1. British imperial (U.S.) Systems British imperial (U.S.) Systems 11.)11.)00.100.1

2.2. Metric system Metric system 12.)12.)inside micrometerinside micrometer

3.3. Psi Psi 13.)13.)dial caliperdial caliper

4.4. Foot- pounds & Newton meters Foot- pounds & Newton meters 14.)14.)dial indicatordial indicator

5.5. Plastigage Plastigage 15.)15.)depth micrometerdepth micrometer

6.6. O.D. O.D. 16.)16.)dial bore gauge dial bore gauge

7.7. I.DI.D. . 1717..))feeler gauge feeler gauge

8.8. Micrometer Micrometer 18.)18.)wire gaugewire gauge

9.9. Thimble Thimble 19.)19.)thread pitch gaugethread pitch gauge

10.10. sleeve sleeve 20.)20.)straight edgestraight edge

Precision measurement is needed to:Precision measurement is needed to: Mass produce products ( assembly line)Mass produce products ( assembly line) Interchangeability of partsInterchangeability of parts Function of assemblies ( oil clearance - ect) Function of assemblies ( oil clearance - ect) Correct fit of assembly.Correct fit of assembly.

In one sixteenth of an inch (1/16) there are In one sixteenth of an inch (1/16) there are sixty two and one half thousandths sixty two and one half thousandths (.0625) (.0625)

Fractions are not accurate enough for the Fractions are not accurate enough for the automotive industry. Every part on your automotive industry. Every part on your vehicle is manufactured using precision vehicle is manufactured using precision equipment capable of accuracy within equipment capable of accuracy within thousandths of an inch. thousandths of an inch.

Decimal systemDecimal system

1 . 5 6 81 . 5 6 8One’s Tenth’s Hundredth's Thousandth’s

4 place decimal4 place decimal

1 . 2 5 7 91 . 2 5 7 9One’s Ten’s Hundred’s Thousandth’s Ten Thousandth’s

Precision MeasuringPrecision Measuring

ToolsTools

Outside MicrometerOutside Micrometer

Outside mic’s come Outside mic’s come in one inch in one inch increments ( 0-1 1-2 increments ( 0-1 1-2 2-3) 2-3)

Can measure to the Can measure to the ten thousandth of an ten thousandth of an inch.inch.

Use three scales to Use three scales to get the reading. get the reading.

Outside MicrometerOutside Micrometer

Outside mic set

standards

Dial CaliperDial Caliper

Measures 0” – 6” O.D. I.D. & depth with .001 accuracy

Dial indicatorDial indicator

Checks for movement .001 accuracy

Snap Gauge (set)Snap Gauge (set)

Can a snap gauge give you a dimension?

Dial Bore gaugeDial Bore gauge

Best tool to check engine cylinder Bore - .0005 accuracy

Feeler gaugeFeeler gauge

Used to check ________ .001 accuracy

Spark plug gap gaugeSpark plug gap gauge

Thread pitch gaugeThread pitch gauge

Metric & std.

Straight edgeStraight edge

Accuracy along length - .001Always used with feeler gauge

Torque wrenchTorque wrench

Foot LBS. In LBS. & Newton Meters How many Ft. lbs. should wheel lugs be?

Plasti-gaugePlasti-gauge

Plasti-gauge crushed on journal Indicated clearance

crankshaft

Parts of an outside MicParts of an outside Mic

spindle

Anvil - carbide

Frame

Sleeve or barrel

Spindle lock

Thimble

Ratchet

How to Read a How to Read a MicrometerMicrometer

.025

.025

.500.010

Total : .535.025

Try these Mic’s

Micrometer PracticeMicrometer Practice

Read Thimble secondRead sleeve first.025 +

.025

.050 total

.125

.130

How to read a Dial How to read a Dial CaliperCaliper

.100

Read first

Read dial second

Total .100

.050

.739

1.000

Dial = .010

Total 1.010

This thing was actually used to BBQ!