LECTURE 2 Production Engineering

designer to produce a product
Primarily based on part print analysis

The

need to have desired
Form
Fit
Function
Interchangeability


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understand drawings!

GD&T standard --
Replaces ASME Y14.5 – 1994
“Considered the authoritative

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for a feature:

Basic dimensions
Considered theoretically perfect
Basis for variations established by _________

dimension and plus-minus tolerance

general note
In the drawing title block
As applied to the dimension

part is OK?
a)
b)
c)
10.5
1.0
10.5
1.0
1.1
10.5
1.0
1.0

limits control surface form.”

symbols
Datum feature and datum target symbols

Outlines of features (profile)
Location of features
Orientation of features
Relationship of

held on _____________________.
One cylindrical or spherical surface, or a set

S

M

L

I

dimensioning symbols, excluding geometric dimensioning and tolerancing symbols, found on

compartments

0.13
M
A
B
C
M

for each of the items found in the feature control

of size of the actual mating envelope of the feature

S

(symbol under ASME Y14.5-1994;
redundant and not used under ASME Y14.5-2009)

contains the maximum amount of material within stated limits

For example
Largest

M

shaft?


For the hole?

contains the least amount of material within stated limits

For example
Smallest

L

0.25
∅ 10.5 ± 0.25
Shaft
Hole
L

form at MMC

Exceptions
When still in purchased condition stock size
When subject

I

inches or millimeters?

b) Refer to the ∅4.4997-4.4994 dimension:
What is

between the maximum material limits of mating parts (tightest fit)

between the least material limits of mating parts (loosest fit)

Formula:
LMC HOLE
–LMC SHAFT
CLEARANCE

now!