Lecture 4 Flashcards
What are the two types of working drawings
Detail and assembly
What do detail drawings communicate
Shape of features, Size and location of features, size, and materials finish and quailty
What is the purpose of dimensions
To provide a clear and complete descrition of the object
What are the dimensioning guidlines
acuracy, clearness, completeness and readability.
What is a dimension line
a thin line, broken in the middle to allow dimension value with arrows at each end
what are the dimensions of the arrow head
3mm long and 1mm wide
What does an extension line do
entends a line on the object to the dimension line
How far should the first dimension line be from the object
12mm or .6 inch
where do extension lines begin
1.5mm from the object and 3mm from the last dimension line
What is a leader
A thin line used to connect a dimension with a particualr area
What are the different dimenson categorys
Linear
Angular
Cylindrical
Radial
When is the cylindrical dimension category used
non hole single curved surfaces
when is radial dim cat used
for curved surfaces under 180 deg
What are dimension rules
dimensions should be in most descritive view
dim are read from bot of page to the top
show machining processes with callouts
How far apart should parallel dimensions be
1/4 inch
How many mm in 1 inch
25.4mm
What are the two standards
ANSI Y14.5 – break the dimension line
ISO R1101 – text over dimension line
How are holes dimensioned
local note or call out in their cicular view
what is the counter bore symbol
recantgle without the top line seagment
what is the counter sink symbol
a V
The depth symbol is what
line with an arrow pointing downward from bot
