Lecture 2 Flashcards
How to get the right sketch for a revolved part
1.Which axix would be serve as the axxis of roration
2.What shape is your starting point from the revolved boss/base feature
Chamfer vs fillet
Chamfer refer to angled or beveled edeges
fillets refer to rounded edges
What is an additive process
It is an example od additve manufacturing, where material is added in sequential layers to create the final object
Benefits to 3D printing
1.Rapid prototyping-make a mock up of design really quickly
2.Minimal waste-using what you need because you go layer by layer
3.reducecost-reduce cost by mock up to see if design works better ebfore you buy
4.energy saving-technology, precise, material cheaper before you buy
Two types of 3D printing
1.Fillamend 3d printers
-more accessiable and common
-It heats and cools the polymer fillament as it is dispense in layers
2.Resin 3d Printing
-most precise and expensive
-utilizes beams of uv light to cure resinous polymer into the desired shape
3d printing consideration
1.tolorancing between parts/features
2.shrinkage and expansion
3.In fills
4.wall thickness
5.overhngs and supports
The diamter of the circular hole is 2.0 inches.WHat does it need to be to fit
shapes must be less than 2.0 inches
tolorance
The allowable variation of a given dimension to achieve proper function-depend on function of th epart
tighter toranceing
more expension and costly because you have to be precise
Nominal Size
Basic size
Nominal size-used for general description not exact like 2x4 \lumber or 1.5x3.5
Basic size-nominal size that get converted to a decimal like 5/8in screw is 0.6250 major diameters
Lower limit and upper limit
1.Lower limit:smallest allowable size for a dminesion
2.Upper limit is the largest allowable size for a dimesnsion
Tolerance math
tolerance is the upper limit-the lower limit
Minimum clearnace
lower lmit of the hole-Upper limit of the shape
Maximum clearance
upper limit of the holes -lower limit of the shape
clearance or free fit
The shaft is always smaller than the hole it interfaces with
positive and minimum maximum clearance
Interference fit
The shaft is bigger than the hole it interfaces with
negative mimum and maximum clearnace
(Ikea funiture need to be hammered inplace)