midterm Flashcards
first angle
F then L
third angle
F then R
difference between isometric and trimetric
circles in an isometric will be the same amount foreshortened no matter what face they are on
in a trimetric they will be foreshortened different amounts
incline faces in multi view drawing
will show in two views and will be a line in the third
normal planes in a multi view drawing
will show on only one view and will be a line in the other two
oblique faces in multi view drawing
will show in all three drawings
general
basically anything that isn’t full scale or half scale but is full scale on the front
cavaliere
full scale on both sides
cabinet
full scale on front and half scale on the side
determining isometric view
it is isometric if lines are parallel and you can make the front cornet into an x and y axis with two 30 degree lines coming up from the positive and negative x axises
determining oblique view
oblique views show the true shape on the front. if the drawing has a true square or a true circle on the front that is not foreshortened then it is an oblique
determining perspective view
parallel lines on a perspective view are converging.
determining trimetric view
circles or squares on a trimetric view will NOT be foreshortened equally like in an isometric view
are lines parallel on an object also parallel on an axonometric view?
yes
how many views are necessary to show height depth and width
2
in cabinet oblique drawings
two axes are perpendicular
not all faces are equally distorted
is scale stated as a ratio of the number of actual units to the number of drawing units
no
in isometric drawings what lines are drawn true length
the lines that follow the guide box
what is bi directional acciotavitivaty
The changes made in a part file are reflected in the drawing and assembly files and the reverse is true.
three negatives of wireframe models
No rendering capabilityAmbiguous
No volume information, which limits analysis capabilities.
types of CAD
2 dimensional
wireframe
surface model
solid model
2 dimensional examples
floor plan
site plan
detail drawing
cons: difficult to visualize, cant analyze or optimize
wireframe examples
cons: only edges and contours are represented
no surface or volume information
surface model examples
cons: doesn’t show interior information
good for wind experiments
solid model examples
easy to visualize and manipulate
easily able to analyze and optimize
can easily feed to CAM in additive manufacturing process to 3D print
what is the only type of projection that is not parallel
perspective
