Chapter 11: Threads and
Fasteners
Agenda
Why they are important
Creating Threads and blocks to re-use them
Creating Hexagonal Bolt and Nut shapes
2
But First…TEST 2 !!!
Next Saturday 1-2PM
Will Cover: Chapters 6 -10
Sectional Views
Auxiliary Views
Dimensioning
Tolerancing
Geometric Tolerancing
Open Book and Notes
You may be asked to do a hand sketch
• Practice Visualizing aux views…see examples3
Sample Auxiliary View Problems
4
Threads and Fasteners
Most mechanical objects need to be held
together
DesignCenter choices are somewhat limited
More flexibility and better clarity by
making our own and saving for later use
We’ll use them next week:
working drawings
5
Design Center Demo
Pre-constructed blocks
Choose Fasteners, US or
Metric
Place, resize, etc
6
3 ways to represent threads
7
Threads—
terms and specs
Pitch in threads/mm
or threads/inch
Preferred Metric Threads
8
Thread specs for English Units
(Inches)
9
Detail Thread (Inches)
10
Creating wblocks
After drawing the object you want to re-use
Select the object
Type “wblock”
Choose a filename reflecting it’s content:
• DETLIN-1in
And a place to store it (myDocs, Desktop, USB)
Then you can choose Insert>Block, find the file,
and insert (rotating or scaling first as needed)
11
MM thread
Or try
scaling the
inch thread
by 20 and
saving as a
new wblock
DETLMM
12
Internal Thread
explode then erase, Hatch ANSI 31
13
Schematic Thread
14
Metric Thread, scale inch by 20
Save as
SCHMMM
15
Internal
Schematic
Thread
Scale by 36/20=1.8
Section using Hash ANSI31
16
Simplified thread
Draw hatch before hidden lines
17
Ortho & Sec
Views
Internal Threads
18
Bolts, Nuts, Screws, Studs
19
Nuts and Bolts
Hex Head Bolts HEXHEAD-10mm.dwg
Distance across flats should be 1.5D
D=major diameter of the thread
Head thickness should be 0.67D
Finishing Nuts FNUTHEX-10mm.dwg
Thickness = .88D
Locking Nuts
LNUTHEX-10mm.dwg
Thickness = 0.5D
Insert and scale to Major Diameter of thread
20
Sample Problem 11-1
Threaded hole depth
Pilot hole depth
21
SP11-2: Length of bolt
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