Introduction to CAD with “OnShape”
Day 2
Lesson Outcome
Focus on fundamental CAD concepts specific to Onshape including:
OnShape
The OnShape Model: 3 Design Environments
Parts
Assemblies
Drawings
OnShape is ASSOCIATIVE
So?
What’s it mean that OnShape is associative?
OnShape is FEATURE-BASED
OnShape is PARAMETRIC
User Interface
} Menu bar
Resources Pane
Feature Manager Pane
Graphics Area
“Document” subWindow
} Tabs to switch between project files
Introduction to OnShape
Basics of Sketching
Let's do this!!!!
1) Log in to OnShape account
2) Click “My OnShape”
3) Click “Create”
4) Select “Document” and name it “L-Bracket”
This is the Main view - NOT the individual sides!
Notice: There aren't any line, circle, or other drawing creation tools in the toolbar.
Before moving on, we need to create a sketch of the side we are trying to draw.
Then the needed tools will appear.
Viewing the proper side to sketch
5) Click “Sketch”
Selecting the proper pane
6. click somewhere on the “front” pane.
Should look like this
Notice that the 3D image is still there but now we have and active “front” pane that can be sketched.
Rotate the pane for ease of sketching
The front view should look like this
Note where the origin is located.
Notice the new tool panel available
These can only be seen in the sketching a pane mode.
They can be used to create various shapes of any drawing.
Objectives: Basic Sketching Practice
1. Practice sketching using a variety of sketch tools.
2. Practice applying constraints to sketch entities.
3. Learn when to apply a constraint vs a dimension to an entity.
4. Create a fully defined sketch.
5. Create a basic part by extruding the correct sketch face.
We will be creating this part with proper dimensions
From OnShape 1.2.1 - Exercise - Basic Sketching.pdf
1. Now use the Line tool and circle tool to create the sketch profile shown on the right.
Be sure that the center (of the drawing?) is not sketched as the midpoint of the vertical line.
(Hint: Note the location of the origin)
If you mess up
Dimensions
2. Add dimensions to fully define the sketch geometry using the “Dimension Tool”
3. Experiment by selecting line segments, or combinations of lines and points as you place each dimension, and type in the values shown.
(Hint: Be sure to select the top and bottom circles along the vertical line and make them equal. 0.75”)
Creating Construction Lines
4. Change the vertical and horizontal lines to construction lines using the “Construction Tool”
Adding connection lines and constraints
Constraints? Are basically limitations or restrictions that tell each line how to behave.
What is a “tangent line”?
Defined: A line that intersects a circle (or curve) at one single point.
Example “Line l is tangent to the circle at point P”
Property: A tangent line is perpendicular to the radius of the circle
Examples of tangents to a circle
Line that is tangent to a curve.
NOTE: You will need to click on both the circle and the line to add a tangent constraint. (see next for clarification).
5. Add lines that connect the outsides of the circles as shown in the sketch profile to the right.
6. Fully define the lines by adding “Tangent” constraints between each line and the circle it connects to.
Using the tangent constraint
Click “Sketch 1”
Click “Show Constraints”
Adding Tangent Constraints
The “Tangent Tool”
This denotes that the line is tangent to one of the circles.
Which one?
Hint: Hover over the tangent icon to see which one it is refering to.
Break away to my OnShape sketch to see how hovering works
Double check
Adding more features to the part
7. Create five additional circles and make them equal.
8. Create a Sketch Fillet at the inside corner of the “L” where the two tangent lines intersect
9. Add the remaining dimensions to fully define the sketch.
Circle
Circle
Circle
Circle
Circle
Fillet
Ready to Extrude? (create a 3-dimesional part)
Ready to Extrude? (create a 3-dimesional part)
10. Create a new part by extrudng the correct sketch faces.
(To create an Extrude, click on the “Extrude Icon” in the toolbar, then select the settings shown on the right and click the green check.)
Set the depth of part to .12”
Other feature: Finding the Area of a part
- While in the sketch view, you can click on any part and see the area.
Try finding the area of the whole piece. Solution on next slide.
Other feature: Finding the volume of a part
1. Select the part “Part 1” in the features list.
2. Click on the balance icon that appears in the lower right hand corner of the OnShape interface.
Share your completed sketch with me
Recap and review
Compare drawing to our first one.
1. Measurements?
2. New tools introduced?
3. Face used?
4. Where was the origin?
Try it! depth extrude: 25mm
Share your completed sketch with me
Working with angles and other features
Practice:
#8 “Anvil”
Extrude to 1-7/8” thickness
Set origin where ever you want.
Things you need to be aware of:
More things to be aware of:
Typed
displayed
Notice, I used dimension lines to adjust my drawing lines
Method: Working with dimension lines on the one corner
Don't forget to extrude!
Extrude to the front!
Or extrude to the back!
Method 2 - using a centerline to measure out
Share your completed sketch with me
#2 “Hook”
Extrude to 1” thickness�
#3 “Buckle”
Extrude to 1” thickness
#14
“Lock Finger”
Extrude to 1-7/8” thickness�
“Bench”
“Game Piece”
Extrude to .125”
Adding features and other helpful hints
Sketching in Context Objectives
Activity Link - click on address below
Note: make sure you are already logged into OnShape and then select “make a copy”
Hint: Be sure to make the large arc, the circle, and the vertical construction line coincide at the same point.
�
7. Add the necessary constraints and dimensions as shown. (the dimensions are in mm - millimeters)
Notice type all mm measures in and it converts it to inches
Remember that arcs are marked as radius and circles are diameters.
Hint: Relations suc as Tangent, Perpendicular, and Vertical may be required to fully define sketch.
8. Create a construction line that connects the midpoints of the two vertical lines on the sides of the profile (this may have already been done)
9. Mirror all the sketch entities of the tab profile about the construction line.
(I did not get a chance to figure out how to do this yet)
Goals: Even more features
Revolve, Sweep, Fillet, and Chamfer
We will be creating a highly detailed version of this part.
Directions
Step 1. Open the Onshape document at:
Step 2 Select “Make a Copy”
Step 3 Watch the following short video: (located on flash drive)
6 Revolve Feature - Basics - Onshape 3D CAD
2.1.2 - Revolve.mp4
Step 4 Create the Revolve feature shown to the right using the copied sketch.
Directions on next slide.
Step 5 Watch the following short video: (located on flash drive)
2.1.1 - Extrude.mp4
Step 6 Create the Extrude on the left side of the part using the copied sketch. The thickness should be set to 0.25 inches.
(Hint: Be sure to select the correct sketch faces and end types for both features.)
Problem: Extrude the flat left end so that the part remains symetric.
Directions on next slide.
Check it: Did it work? Nope? BAD! See below
Not symmetric?
Locate the drop down menu that now reads “Blind”
Change the “Blind” to Symmetric
Then click the green check
Note: A feature is that the blind arrow indicates which way it it to get Extruded. If you flip the arrow it extrudes the other direction.
Select the right side of the part
Select the Right face of the part
Select “Sketch” (make sure you did not select “Sketch 1”, this should be a new face sketch that gets added the the drawing.)
“Sketch 2” should appear
(may have to constrain them to be tangents and perpendiculars)
Should look like this
Same photo with constraints shown
Step 8 Create the extrusion (of the end piece you just created) on the right side of the part.
The total thickness of the extrusion is .3”, and extends into the part by .05 inches.
Hint: you will need to use multiple features within the Extrusion drop down to create this.
Directions on next few slides.
Solution: Here's how
(there are 3 total)
The extrude should be a total of .3” (this was 1” default... we will change this in the next slide.
Creating holes of a certain radius and depth
Goal:
Create the sketches for the two holes on the top faces of the part using a diameter of .12” for each hole
Extrude the hole on the left to a depth of .7”
Extrude the hole on the right to a depth of .41”
Note: Remember these measures.
Step 9 Create a holes on the right and left side of the part that extrudes up to the face shown in the image.
Creating hole on the right
Create a new sketch by clicking the top of the right face and select “Sketch”; a new sketch should appear as “Sketch 3”
Creating and Centering the circle
Ignore this menu, it was done by right clicking and the only way I could get a screen shot.
Extruding the circle (removing material)
Did it work?
Creating the left hole
Fillet Video
Adding fillets
Sep 10 - Add fillets to the edges of the cylinder using .05 radius
Step 11 - Add fillets to all external edges on the left side of the part (excluding the hole) using .05 radius
Step 11 - Add fillets to all external edges on the right side of the part (excluding the hole) using .05 radius
Note: you can do them all within one fillet drop down, but you will need to rotate several views of your part as you do them
Putting it all together: Complete book diagrams
Videos
Next Activity - Basic Features 2
Directions
Step 1. Open the Onshape document at:
Step 2 Select “Make a Copy”
Step 3: Determine which two sketches in the features list can be used to create the sweep feature for the handle.
Show these two sketches in the model.
To determine which two sketches are to be used, play around with the sketches and (right click and hold somewhere on the open space of the drawing) move the vase around several different views and it becomes apparent that sketch 5 and 6 are the ones that form the profile of the handle.
Look at the front-right, front, and front-left view of Sketch 5
You can see and egg shaped profile that will become the shape of the handle after sweep
Now look at the Right view of Sketch 6
Sweep path will appear here.
Go to next slide.
Step 5 - Creating the inside of the pitcher
However, we need to create a vessel that would hold a liquid.
We can do this by using what is known as the “rollback bar” function. This feature allows us to place a function in the features list between exisiting features.
- Determine where to place the rollback bar in the features list to create the “shell” feaure as it appears in the image to the right.
Create a shell that has a thickness of .25”
How to:
We need to be able to remove the material or “create a shell” after “Extrude3” in the features list.
To insert a new feature just after Extrude3, right click on Extrude3, scroll down and click “Roll to Here”
Note: I tried doing this after “Revolve 1” but it did not work. I kept moving ahead in the feature list to determine that it should be after “Extrude 3”
Shell 1 will appear as well as new drop menu, ready to select thickness and face to “Shell”
Click the “Shell” icon.
Then click the green check
The vase should look like this with the handle sticking inside.
select all parts of inner extrusions
“Cap” smooths out the gaps on the inside of the pitcher when deleting faces.
Adding a profile to the TOP of the pitcher
Create a wavy extruded surface in the features list that cuts through the top of the water pitcher.
We will use the “Replace Face” function tool to replace the upper rim of the pitcher with the wavy extruded surface.
Set the offset distance to “Zero”
Then hid the wavy extruded surface.
Goals:
1. Create a new part within the context of a part studio.
2. Learn to assess which faces and/or planes to use for sketching.
3. Practice creating extrudes, fillets, and chamfers from sketches and features made by your.
Right click and rotate the part so you can see the face under the tip of the top bearing on the left.
https://cad.onshape.com/documents/2e7ea22bcffc498c8d4f1b79/w/32854cb9f9e0466abbe4eaee/e/8ec249ad3b1245758ba0eaa0
Create the sketch shown in the image on the right.
(Hint: In order for the geometry to fit the bearing, some sketch entities must be created by projecting existing geometry onto the sketch plane.
Advanced sketching techniques
1. Create a sketch profile by utilizing geometry from existing part.
2. Apply a variety of sketch constraints.
3. Learn how to speed up the design process when a part is symetric.
4. Enable the new part to update when the existing part is modified.
Activity overview
We will be taking this existing part and adding tabs to it... so that is looks like.... psst next slide
This!!
Basically -
+
=
1. Start with the following file - open the web link
Sketching in Context
So what are we creating?
Rough sketch of shape - NO measurements yet
Hint: Be sure to make a large arc, the circle, and the vertical construction line coincident at the same point
Add measures and constraints
5. Add the necessay constraints and dimensions as shown in the image.
Hint: Use tangent, Perpendicular, and vertical may be required.
Larger view on next slide