Exam 2 Flashcards
(34 cards)
When an instance of a part is brought into an assembly how many degrees of freedom does it have before any constraints are applied? #11
6
11
describe associativity? #11
it is like a cloud system, where if you change a feature on one part all instances will also change
11
What is the difference between components and instances?
Components are the parts that make up a system, while instances are copies of the components
11
describe a subassembly
a group of components that serve a single purpose
11
what is the purpose of assembly constraints and what are they called in solidworks?
assembly constraints help set the dimensional relationship between instances, they are called mates e
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In assembly modeling, the copies of a component within the system are called
instances
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in assembly modeling, you can apply ____ btw two 3-D instances so they maintain their geometric relationships within the assembly
assembly constraints/ mates
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An assembly that is fully constrained is ______
a. dimensional b. concentric c. rigid d. movable
rigid
What is the diff between interferences and clearances when trying to mate 2 parts in a assembly? #11
Clearance is the minimum distance allowed between parts, like when the shaft of a screw is a lot smaller than the hole. Interferences is the amount of overlap btw 2 parts when a screw is much larger than the hole
12
Why is MBD (model based definition) so important?
it allows us to annotate and define 3D models on CAD instead of having to present all the information with 2D drawings
12
describe the purpose of Multiview presentation
it allows us to view all views of a part on the same plane
12
How are viewing planes related to orthogonal projection?
viewing planes are transparent planes that are fixed to your line of sight, while orthogonal projection is the projection of a 3d model on the viewing plane where a face is parallel to the plane
12
What are object lines?
They are the visible and dark lines that represent edges
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What are hidden edges?
They are the dotted lines that represent the obscure and blocked off features
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What are centerlines?
They mark the center of a circular hole with 4 lines
12
What is the difference between first angle and third angle projection?
Third angle uses 3 views with the front view being the rear view, while first angle uses 6 different views
12
What is a pictorial view? and the 3 types?
It is a view that allows you to see 3d objects. The 3 types include isometric, perspective, and oblique.
What is the difference between isometric, diametric, and trimetric views?
isometric has all surfaces with equal angles of 120 degrees, diametric has 2 same angles, and trimetric has all 3 different angles
What view should u use if you want to see features that are hidden on a Multiview drawing?
a section view because it gives a view of a cross section showing the features
Why is using the auxillary view important?
It allows us to see the true surface of an inclined or oblique surface, instead of a isometric or perspective view it replaces it.
What is the difference between a chain and baseline dimensioning?
Chain is when you start your dimensions from where you left off, while baseline is when you dimension everything starting at the outside edge
What is the national standard for dimensioning?
ANSI y14.5
What units do the US and the world use?
The US uses decimal inch, while the world uses millimeters
What are the rules when dimensioning drawings using millimeters?
less than 1 use leading zeros, but don’t use trailing zeros
so like 0.1
