1. Precision Measuring Precision Measuring Gateway To Technology®
Unit 1 – Lesson 1.3 – Measuring
Precision Measuring

2. Precision Measuring Precision measuring tools are needed for accuracy
Gateway To Technology®
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 needed for accuracy

3. Tools for Precision Measuring
Gateway To Technology®
Unit 1 – Lesson 1.3 – Measuring
Steel Rule
Micrometer

4. Tools for Precision Measuring
Gateway To Technology®
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

5. { Reading a Dial Caliper The dial caliper is a precision measuring
Gateway To Technology®
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.

6. Reading a Dial Caliper The caliper’s dial graduations are
Precision Measuring
Gateway To Technology®
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.

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

8. Dial Caliper Parts Inside Measuring Faces Dial Clamp Screw Blade
Precision Measuring
Gateway To Technology®
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

9. 2 Reading a Dial Caliper Step 1 Read inches from the blade
Precision Measuring
Gateway To Technology®
Unit 1 – Lesson 1.3 – Measuring
Step 1
Read inches from the blade 2
1 in. – 6 in.

10. 2 3 Reading a Dial Caliper Step 2 Read tenths of an inch from
Precision Measuring
Gateway To Technology®
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.

11. 2 3 2 8 Reading a Dial Caliper Step 3
Precision Measuring
Gateway To Technology®
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 in.

12. How to read a caliper (Click on the black part to play video)

13. Now it’s your turn!
Ask Mr. Yung for a Dial Caliper and a Ruler. Measure the items listed with a ruler first in inches. Then use a dial caliper to measure the accurate measurement.

14. Dial Calipers Measure Thickness or Outside Diameter
Precision Measuring
Gateway To Technology®
Unit 1 – Lesson 1.3 – Measuring
Dial Calipers Measure
Thickness or Outside Diameter
Inside Diameter or Space Width

15. Dial Calipers Measure Thickness or Outside Diameter
Precision Measuring
Gateway To Technology®
Unit 1 – Lesson 1.3 – Measuring
Dial Calipers Measure
Thickness or Outside Diameter

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

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

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

19. Precision Measuring
Gateway To Technology®
Unit 1 – Lesson 1.3 – Measuring
Image Resources
Microsoft, Inc. (2008). Clip Art. Retrieved October 10, 2008, from
Wikimedia commons (2008). Retrieved October 15, 2008, from