Print Reading Flashcards
Orthographic print is what?
Representing a three dimensional object on a print.
What are the six different planes of an orthographic projection?
Front Right Left Top(plan) Bottom Rear
What is the key view in orthographic projection?
Front view
What are the two different types of orthographic design?
First angle projection,
Rare in North America
Third angle projection,
Most common in North America
What is the order of view for third angle after the front(key view) view is drawn?
- top view is placed above
- right side view is placed on the right
- left side view is placed on the left
- bottom view is placed below
- the rear or back is placed on the far left
What is the order of view for first angle after the front(key) view is drawn?
- Top view is placed below
- Right view is placed on the left
- Left view is placed on the right
- Bottom view is placed on top
- rear or back view is placed on the far left
Why are top and right side views important?
Because a 2 dimensional print will not show around corners.
When reading blueprints what terms are used to refer to measurement?
Width = W
Height = H
Depth = D
What does the circle represent when looking at projection symbols?
Front view
- third angle, the right side view goes to the right of the front view.
- first angle, the right side view goes to the left of the front view.
What is a pictorial view?
A view with three dimensions.
What are the types of Pictorial views?
Perspective: less common in mechanical trades. Front view is undistorted and the top and right side taper into distance
Oblique: front face is undistorted, but other two faces are distorted in proportion to the angle on the scale.
Isometric: most common in mechanical trades. Front view is a 30 degrees from horizontal. Which makes all three axis 120 degrees apart
Most important line on a sketch?
Object/visible line: THICK
What does the centre line look like?
Thin, broken line made of alternating long and short lines.
What is the purpose of a hidden line? What does it look like?
The hidden line is used to show objects hidden from view.
It is made up of a series of medium dark short dashes.
What are extension and dimension lines used for?
Extension lines extend from but do not touch the object. Used with dimension lines to signify the distance.
Dimension lines indicate the distance
What is a cutting plane line?
Thick, dark, broken or continuous lines with arrows at right angles on each end. Signifies where the sectional view was taken
What does a phantom line represent?
It shows a mating part or assembly movement of an object.
What does BC stand for?
Bolt circle
What does BHC stand for?
Bolt hole centre
what does BCD stand for?
Bolt circle diameter
What does C to C stand for?
Centre to centre
What does CTRS stand for?
Centres
What does D or Dia stand for?
Diameter
What does TYP stand for?
Typical
What is an arc?
Segment of a circle. Should be dimensioned by its radius rather then diameter.
What is a counterbore?
A hole that has been enlarged for a portion of its depth.
What two standards are threads shown in?
American national standard institute (ANSI)
And
Canadian standards association (CSA)
What are three views threads are shown in? I
Schematic
Pictorial
Simplified (most common)
What is free length?
Length of the spring when it’s under load or stress.
What are the two types of bearings?
Anti friction bearings -
Plain bearings
What is the difference between aligned method and unidirectional dimensioning?
Aligned method all dimensions are written parallel to the dimension lines
Unidirectional method all dimensions are written parallel to the bottom of the drafting paper
Third angle glass box theory helps visualize what they are talking about. See image
What is the difference between a spot face (SFACE) and a counterbore?
Spotface has no specific depth. Main function is to provide a flat seat for the head of a bolt or washer
Counter sink symbol and abbreviation
Break lines
Steel symbol
Cast iron symbol
Aluminum symbol
Brass/copper/bronze symbol
Lead/zinc/babbit symbol
S shape
W shape
