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Feature-Based Modeling and
Optional Advanced Modeling
ENGR 1182
SolidWorks 05
Today’s Objectives
 Feature-Based Modeling (comprised of 2 sections as shown below)
1. Breaking it down into features
 Creating Construction Centerlines
 Construction Centerlines to Create Holes
 Constraining Circular Patterned Holes
2. Edge Features(3D Fillets & Chamfers) and Model Tree
 SW05 In-Class Activity
 SW05 Out-of-Class Homework Assignment
 Optional Advanced Modeling –Methods to Save Time ( Planes, Axes,
Mirroring & Patterning, Holes, Shells, Sweep, & Loft) with HYPERLINK
navigation
Feature-Based Modeling
• Break down into Features
• Series of Steps
• 1st Step: Base Feature
• Adding / Subtracting Material
• Edge Features
• Model Tree
Breaking it Down into Features
ENGR 1182
SolidWorks 05
Breaking it Down into
Features
• Objects can be
thought of in terms of
features
•
•
•
•
Shapes
Holes
Rounds
Etc.
• Determines design
strategy
Feature Modeling
Example
Series of Steps
• Base Feature
• First Extrusion or
Revolve
• Reduce Steps of
Construction
• Features
• Additions or
subtractions from
original base feature
How many different ways
could we make this?
Example Construction 1
We can think of the block in
terms of 2 “L” shapes and
then cut out the hole
Example Construction 2
We can think of the block in
terms of a “C” shape and then
add the plank with a hole
Example Construction 3
Finally, we could draw the overall
shape from the top view and
remove unwanted material
An Important Concept
 Most sketches can be greatly simplified by
establishing horizontal and vertical
"Centerlines" and then applying constraints
employing those construction centerlines.
When the object exhibits symmetry, those
construction centerlines are often drawn
though the origin. Many sketches will be
much easier to constrain if one uses
horizontal and vertical construction
centerlines. Typically used constraints
include dimensioning, symmetry and equal.
 So even if you don’t initially recognize a
need for vertical and horizontal construction
centerlines, it is a very good practice to
include them in your sketches!
Using Construction Center Lines
to Position Multiple Holes
In the sketch mode insert
a construction line of
infinite length at a 45O
angle through the origin
Draw 4 center point
circles on construction
lines and make them
equal
Repeat procedure at a
-45O angle through the
origin
Establish Symmetry
for each pair of circles
Dimension
Exit sketch and perform an
Extruded Cut through all
A Short Cut Method to Produce
Multiple Holes
In the sketch mode insert
a construction line of
infinite length at a 45O
angle through the origin
Sketch a single circle on the
construction line, locate and
dimension the circle
Note that the number 4 could
have been set to any number
… 2, 3, 8,etc
Select Linear Sketch Pattern/
Circular Sketch Pattern
Select the drawn circle
Set the number of
circles to 4, accept and
Extrude Cut as before
Breaking it Down
Wrap Up
Breaking it down
 Base Feature
• Start with an extrusion (or
revolve) that contains the basic
shape of the object
• Minimize steps by choosing an
appropriate shape for the base
step (what shape can be used to
build off of)
• Do not try to take into account
every detail, add later with
additional features
 Series of Logical Steps
Homework Assignment SW05-OUT:
Problem 6.4 (ss) from the text.
In-Class Activity
The object to the right can be
created many different ways.
Can you determine at least 2
different methods (starting on
different planes) and create the
same object?
Edge Features and Model Tree
ENGR 1182
SolidWorks 05
Edge Features
3D Fillets create rounded edges
3D Chamfers create slanted edges
2D Fillets vs. 3D Fillets
•
•
2D Fillets are
only to be used
in Sketches
3D Fillets are
used on edges
of the part
(3D Fillets are
extremely powerful in
making realistic
designs)
SolidWorks Example:
Piston Head
How would you break this down into features?
Where would you start? Where would you use the
edge tools? At what point in the process?
SolidWorks: Base Feature
There are a couple ways to effectively
model this piston head but for these
slides we will start with a simple extrusion
of a circle to create a cylinder
SolidWorks: Extruded Cut
The volume will be
removed using an
extruded cut offset from
the bottom surface
SolidWorks: Revolved Cut
The piston rings will be cut out
using a revolved cut
SolidWorks: Review Design
Is there any other way that we
could have reached this point
and how many steps would it
have involved?
Would it be easier?
SolidWorks: Extruded Cut
The pin hole and groove will be
removed using an extruded cut
SolidWorks: Chamfer
The top slanted edge will be
added using a chamfer
SolidWorks: Fillet
And finally the bottom edge of the
head will be smoothed out using a
Fillet (under the features menu)
SolidWorks: Finished Part
This finished product can
now be used in an
assembly with other
components shown here
SolidWorks: Design Tree
The design tree on the left of the
screen catalogs all the steps of
creating this part and records the
steps from top to bottom
Sketches are absorbed into
features but can be accessed by
clicking the plus sign next to
each feature
SolidWorks: Part Editing
The design tree can be “rolled
back” by clicking and dragging the
blue bar at the bottom up and the
features are no longer shown
New features can be added to
this model in the middle of the
design tree while other items are
still “rolled back”
SolidWorks: Altered
Final Part
These changes will also
carry over to the assembly
that contains the part
When the design tree is restored then all the
features return as long as changes do not
interfere with previous features
Feature Based Modeling
Wrap Up
 Recognize Features of Object
 Start with Base Feature
Homework Assignment SW05-OUT:
Problem 6.4 (nn)
 Carefully consider the use of construction
centerlines in most sketches
 Add or Remove Material in a series of
steps
 Features to add last:
• 3D Fillets: Rounded edges
• 3D Chamfers: Slanted edges
 Editing Features with Model Tree
R3
In-Class Activity
Problem 6.4 (u)
Create the following shape
according to the features and
dimensions.
• First break this object down
into features (you should be
able to create this in 2
sketches)
• Then use 3D Fillets for the 4
rounded edges
Important Takeaways
 Feature-based modeling is used to
break down the features of a part
to create the part in an efficient
way.
 Edge features, like chamfers and
fillets, are used to create different
edge designs efficiently.
R3
What’s Next?
 Due Next Class SW05 Out-of-Class HW
 Before next class, you will read about
assembly modeling.
 Assemblies are collections of 3D parts
that are constrained to form one
engineering system.
 Take SolidWorks 6 Quiz on readings
Optional – Advanced Modeling
• Methods to Save Time
• Methods to Create Shapes
•
•
•
•
•
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Reference Geometry – Planes & Axes
Mirroring
Patterning – Linear & Circular
Hole Wizard
Shells
Sweeps
Lofts
Advance Modeling Wrap Up
In the SLIDE SHOW MODE this page supports HYPERLINK navigation
Optional Advanced Modeling Techniques
ENGR 1182
SolidWorks 05
Reference Geometry: Planes
SolidWorks starts off with
the 3 original planes:
front, right, top
To add a new plane we can
reference previous planes
and create offset new
planes or other options
RETURN TO START PAGE
Reference Geometry: Axes
Axes can also be
created without the
creation of a 2D
sketch
RETURN TO START PAGE
Mirror
Mirroring creates an
reverse copy of
features on the
opposite side of a
mirroring plane
First the Mirror Plane
must be chosen
Mirror
Once the plane has been
chosen then the features to
mirror are selected
The new features are joined
to the original model
RETURN TO START PAGE
Linear Patterns
Once edges are selected for direction, number
of instances and distance are specified in the
dialog box
Features can also be
duplicated in linear patterns
in either one or two
directions.
RETURN TO START PAGE
Circular Patterns
Once features and axes
are chosen the angle
and number of
instances are specified
Features can also be
duplicated in circular
patterns around an axis
Also see slide 12 - Using Construction Center Lines to Position Multiple Holes
RETURN TO START PAGE
Holes
• Mating Parts
• Hole Specifications
• Built-in Hole Tools
• Location and Size
Selected
Holes using the Hole Wizard
1) Under Feature select Hole Wizard 2) Specify the type of Hole 3) Specify Hole Position 4) Add threads
1
2
3
4
RETURN TO START PAGE
Shells
• Removes Volume
• Thin Wall Created
RETURN TO START PAGE
Sweep
Pathways can be
combined with a 2D
profile, such as a circle,
to create what is known
as a sweep
Mirror
complex
features to
save time
RETURN TO START PAGE
Loft
The same shape but different sizes
can be used
Lofting is taking two
profiles on separated
planes and filling the
space between with
material that blends
the original profiles
Loft
Different shapes can be blended into one solid such as the
hexagon is connected to the circles of different sizes
Circular patterns,
fillets, and
appearances can
also be added
RETURN TO START PAGE
Advanced Concepts Wrap Up
Time Saving Methods
 Reference Geometry
• Planes/Axes/Points
 Mirroring
 Linear Patterns
• One or two directions
OPTIONAL:
SolidWorks tutorials
 Lofts
 Pattern Features
 Revolves and Sweeps
Found under the Building Models tab of
the SolidWorks tutorials
 Circular Patterns
Advanced Shapes
 Sweep
 Loft
RETURN TO START PAGE
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