Reading Assignment
- Lab 1 – Measurement
- 10.1 Introduction to Measurement and Testing
- 10.2 Standards of Measurement
- (10.3 Allowance and Tolerance) recommended, not on test
- 10.4 Inspection Methods for Measurement
- 10.5 Measuring Instruments
- 10.7 Coordinate Measuring Machines
- 10.8 Angle-Measuring Instruments
- 10.9 Gages for Attributes Measuring
- Calibration Certificate (pre-NIST)
- Calibration Certificate (NIST)
Recommended Links:
- Handbook of Dimensional Measurement
- Metrology and Quality Control
- Unit Study Guide – Intro. to Measurement
- NIST Gauge Block Handbook
- Video: Nobody’s Exactly Sure How Much A Kilogram is Right Now
Outline
Typically measured values
- Part dimensions – Interchangeable parts
- Size
- Orientation
- Form
- Location
- Time
- Weight
- Temperature
- Pressure
- Hardness
Two systems
- English
- Metric (SI)
Primary Standards
- Instruments calibrated to a primary standard
- Gage blocks & Surface Plates – are used as an internal primary standard (Gage block applet )
- Traceability to NIST
Core Metrology Concepts
- Precision
- Resolution
- Accuracy
- Repeatability
- Reproducibility
- Repeatability and Reproducibility are measured using Gage R&R analysis
Measurement & Gauging Tools
Non-graduated measuring tools & gauges
- Calipers
- Inside caliper
- Outside caliper
- Divider caliper (Dividers)
- Oddleg caliper (Hermaphrodite Calipers)
- Bore Gages
- The telescope gauge
- The small hole gauge
- Machinist Square
- Straightedges
- Adjustable parallels
- Sine bar
- Height of Gage Blocks = Hypotenuse * sin(angle)
- Angle = asin(height/hypotenuse)
- Be sure your calculator is in DEGREE mode
- Sinebar Spreadsheet (for practice)
- Sinebar Video
- Sinebar Calculator
- Radius gage
- Feeler gage
- Screw pitch gage
- Go-no-go gages
Graduated measuring tools & gauges introduction
- Rules
- Combination Square
- Calipers introduction
- Vernier caliper
- Other vernier tools
- Dial caliper
- Digital caliper
- Micrometer
- Depth micrometer
- Dial indicators & dial test indicators
- The dial caliper
- Other tools incorporating dial indicators
- Height Gage
Electronic digital readouts (DRO)
Advanced measuring devices
The optical measuring projector
Vision systems
Pneumatic Comparators (Dimensional Air Guages)
The coordinate measuring machine (CMM)
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