precision measurement. precision measuring precision – how close together or repeatable the...
TRANSCRIPT
Precision Measurement
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
Steel Rule
Micrometer
Tools for Precision Measuring
Digital Caliper
Dial Caliper
Tools for Precision Measuring
The dial caliper is a precision measuring instrument.
The caliper’s blade graduations arein inches and tenths (.1) of an inch.
Reading a Dial Caliper
inch
Each inch is broken into ten, for .1 of an inch.
{
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.
Reading a Dial Caliper
One full revolution of the pointer on the dial equalsone hundred thousandths (.100).
Dial Caliper PartsInside Measuring Faces
Dial Clamp ScrewBlade
Fine Adjustment Screw
Dial Adjustment Screw
Outside Measuring Faces
Step 1 Read inches from the blade
1 in. – 6 in.
2
Reading a Dial Caliper
Step 2 Read tenths of an inch from the blade
Reading a Dial Caliper
1 in. – 6 in. .0 in. -.9 in.
2 3
Step 3 Read thousandths of an inch from the dial
Reading a Dial Caliper
1 in. – 6 in. .0 in.- .9 in. .001 in.- .099 in.
2 3 2 8
Dial Calipers Measure
• Thickness or Outside Diameter
Dial Calipers Measure
• Thickness or Outside Diameter• Inside Diameter or Space Width
Dial Calipers Measure
• Thickness or Outside Diameter• Inside Diameter or Space Width• Depth
Dial Calipers Measure
• Thickness or Outside Diameter• Inside Diameter or Space Width• Depth• Step Distance
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