Precision Machining - Print Interpretation

Views

100

This view shows the most detail

What is Front View?

200

This view sits above the front view in third angle projection.

What is Top View?

300

This view sits on either side in both third and first angle projection.

What is Side View?

400

This view sits below the front view in third angle projection.

What is Bottom View?

500

This view is the least common view.

What is Back View?

600

This view represents the object is 3D form.

What is Isometric?

Lines

100

This line is used to show edges that are visible, this line is thick and continuous line.

What is Object Line?

200

This line show edges that cannot be seen, this line is thin and broken into small dashes.

What is Hidden Line

300

This line is used for dimensioning, this line is thin and continuous with arrows on the ends.

What is Extension Line?

400

This line is used for extending edges to meet dimension lines.

What is Extension Lines?

500

This line is angle with an arrow pointing to a feature, a dimension or note is tied to it.

What is Leader Line?

600

This line is used to make an imaginary cut through an object to show details that may be hidden, creates a section view. This line is thick and has one long line and two short dashes with arrows on the ends.

What is Cutting Plane Line?

Tolerances

100

This is what a dimension shown on a print is called.

What is Basic Size?

200

This condition is when a feature contains the most workpiece material within its tolerance.

What is Maximum Material Condition(MMC)? 

300

This condition is when a feature contains the least workpiece material within its tolerance.

What is Least Material Condition (LMC)?

400

This tolerance allows a dimension to vary both above and below the basic size.

What is Bilateral Tolerance?

500

This tolerance allows a dimension to vary in only one direction from the basic size.

What is Unilateral Tolerance?

600

This tolerance does not use a + or -, rather it uses the upper and lower limits that is allwed.

What is Limit Tolerance?

Mating Parts

100

This is the relationship between the sizes of the two mating parts.

What is Class of Fit?

200

This is the minimum amount of clearance.

What is Allowance?

300

This allowance provides clearance between mating parts.

What is Positive Allowance?

400

This allowance provides interference between mating parts.

What is Negative Allowance?

500

Calculate the allowance

A Shaft has a dimension of .875" +/- .001" and mates with a hole with a dimension of .873" +/- .001". 

What is .004" Negative Allowance?

600

Calculate the allowance

A Shaft has a dimension of 1.3125" +0/-.001" and mates with a hole with a dimension of 1.3125" + .001/-0". 

What is .001" Positive Allowance?

Basic Symbols

100

⌀

What is Diameter?

200

⌴

What is Counterbore?

300

⌵

What is Countersink?

400

↧

What is Depth?

500

°

What is Degree?

600

R

What is Radius?

GD&T I

100

__

What is Straightness?

200

⏥

What is Flatness?

300

⊥

What is Perpendicularity?

400

◎

What is Concentricity?

500

⌭

What is Cylindricity?

600

↗

What is Circular Runout?

GD&T II

100

◯

What is Circularity?

200

⌖

What is Position?

300

∥

What is Parallelism? 

400

⌓

What is Profile of a Surface?

500

∠

What is Angularity?

600

⌰

What is Total Runout?

Computations

100

Total Tolerance:

.236" +/-.0035

What is .007"

200

LMC of a Hole:

.475" +/- .0005

What is .4755"

300

MMC of a shaft:

.8125" +0/-.001"

What is .8125"

400

Convert the unilateral tolerance to a bilateral tolerance.

1.4375" +/- .005"

What is 1.4325" +.01/-0" or 1.4425" +0/-.01"

500

Convert the unilateral tolerance to a bilateral tolerance.

.184" +.006/-0"

What is .187" +/- .003"

600

Find the allowance.

Shaft of 1.121" + .0007/-0"

Hole of 1.121" +/- .0005"

What is .0012" Negative Allowance?