Precision Measuring Precision Measuring Precision How close together

Precision 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

Tools for Precision Measuring Steel Rule Micrometer

Tools for Precision Measuring Digital Caliper Dial Caliper

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

Reading a Dial Caliper 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 one hundred thousandths (. 100).

Dial Caliper Parts Inside Measuring Faces Dial Clamp Screw Blade Fine Adjustment Screw Dial Adjustment Screw Outside Measuring Faces

Reading a Dial Caliper Step 1 Read inches from the blade 2 1 in. – 6 in.

Reading a Dial Caliper Step 2 Read tenths of an inch from the blade 2 1 in. – 6 in. 3. 0 in. -. 9 in.

Reading a Dial Caliper 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

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

Discussion Questions • List measurement tools… Steel Rule Dial Caliper Tape Measure 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

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/Image. Caliper