Precision Measuring Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Precision Measuring Design and Modeling © 2011 Project Lead The Way, Inc.

Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Precision Measuring Precision – How close together or repeatable the results are A precise measuring instrument will give nearly the same result each time that it is used. Accuracy – How close a measurement is to the accepted value For example, a balance loaded with a standard 100 g weight should read 100 g. If it doesn’t, then the balance is inaccurate. Precision measuring tools are used to improve precision and accuracy of measurement

Tools for Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Steel Rule Micrometer

Tools for Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Digital Caliper One of the most common tools for reverse engineering is the dial caliper because of its versatility. Dial Caliper

Dial Caliper Parts Inside Measuring Faces Dial Clamp Screw Blade Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Dial Caliper Parts Inside Measuring Faces Dial Clamp Screw Blade Fine Adjustment Screw Dial Adjustment Screw Outside Measuring Faces

{ Reading a Dial Caliper The dial caliper is a precision measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring The dial caliper is a precision measuring instrument. The caliper’s blade graduations are in inches and tenths (.1) of an inch. inch { Each inch is broken into ten, for .1 of an inch.

Reading a Dial Caliper The caliper’s dial graduations are Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring The caliper’s dial graduations are in thousandths (.001) of an inch. The reference edge keeps track of larger increments; the dial is for smaller increments.

One full revolution of the pointer on the dial equals Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring One full revolution of the pointer on the dial equals one hundred thousandths (.100).

2 Reading a Dial Caliper Step 1 Read inches from the blade Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Step 1 Read inches from the blade 2 1 in. – 6 in.

2 3 Reading a Dial Caliper Step 2 Read tenths of an inch from Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Step 2 Read tenths of an inch from the blade 2 3 1 in. – 6 in. .0 in. -.9 in.

2 3 2 8 Reading a Dial Caliper Step 3 Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Step 3 Read thousandths of an inch from the dial 2 3 2 8 1 in. – 6 in. .0 in.- .9 in. .001 in.- .099 in.

Dial Calipers Measure Thickness or Outside Diameter Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Dial Calipers Measure Thickness or Outside Diameter

Dial Calipers Measure Thickness or Outside Diameter Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Dial Calipers Measure Thickness or Outside Diameter Inside Diameter or Space Width

Dial Calipers Measure Thickness or Outside Diameter Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Dial Calipers Measure Thickness or Outside Diameter Inside Diameter or Space Width Depth

Dial Calipers Measure Thickness or Outside Diameter Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Dial Calipers Measure Thickness or Outside Diameter Inside Diameter or Space Width Depth Step Distance

Discussion Questions List measurement tools… Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Discussion Questions List measurement tools… Steel Rule Tape Measure Dial Caliper Meter Stick Which of the tools listed would be best to use, and why, when measuring: The hallway Engineering Notebook Pencil diameter Height of your desk

Precision Measuring PLTW Gateway® Unit 1 – Lesson 1.3 – Measuring Image Resources Microsoft, Inc. (2008). Clip Art. Retrieved October 10, 2008, from http://office.microsoft.com/en-us/clipart/default.aspx Wikimedia commons (2008). Retrieved October 15, 2008, from http://commons.wikimedia.org/wiki/ImageCaliper