Mechanical assemblies fundamentals - Import geometry then edit with direct modeling

Tutorial resources

These downloadable resources will be used to complete this tutorial:

Import an assembly created on another CAD platform and edit it in Autodesk Fusion.

Import an IGES file

To import geometry created on another CAD platform such as SolidWorks or PTC Creo, upload an IGES file to Fusion.

If the Data Panel is not open, click Show Data Panel .
In the Data Panel, click New Project.
Enter Imported Geometry for the project name.
Double-click the new Imported Geometry project.
Click Upload.
Click Select Files.
Navigate to Gear_Housing.iges, double-click the file, and click Upload. The file is added to the contents of the Imported Geometry project folder.
Right-click Gear_Housing and select Open. The Gear_Housing geometry appears on the Fusion canvas.

Notice that there is no timeline at the bottom of the screen. You are in direct modeling mode, so Fusion is not recording history (as it would if you were in parametric mode). With direct modeling, you can change the imported model even though no history, sketches, or relationships were imported with it.

Remove small ribs

Seeing that two small ribs on the part are unnecessary, you decide to remove them.

In the Model workspace, select all four faces of the first rib. To select faces that are hidden by other geometry, hold down the left mouse button and use the menu that appears.
Press the Delete key.
Rotate the model to select all faces of the small rib on the opposite side.
Press Delete.

Edit fillets

Further investigation of the model shows that one of its fillets isn't tangential to neighboring faces. You remove and replace it.

Zoom in and select the problematic fillet.
Press Delete. The neighboring faces of the removed fillet now form a sharp edge.
Select the fillet on the opposite side.

Information shown in the lower-right corner of the screen indicates that the existing fillet has a radius of 20 mm. Using this dimension, create a fillet to replace the one you removed.
Select the edge for the new fillet.
Right-click and select Fillet in the Marking menu.
Enter 20 mm.

The fillet is replaced.

Remove a stepdown

In this step, you remove an unneeded stepdown area at the back end of the model. Direct modeling makes this task easy, because you can change one part without affecting other parts.

Zoom in to the area and select the faces you want to remove.
Press Delete to remove the stepdown.

Note: Without direct modeling, you might have to recreate a profile and extrude it, but that would cover up the recess. You would then have to create another profile to project up through that extrusion. The extra geometry could cause modeling issues. With direct modeling, you just select the faces you want to remove and delete them.

Move the cylindrical boss

In this step, move and rotate the cylindrical boss to line up with another part.

Dragging from left to right, draw a selection rectangle around the area to move.
Right-click and select Move/Copy in the Marking menu.
Use the vertical manipulator to move the boss to a distance of -3 mm.
To rotate the boss cylinder and support arm, right-click and select Move/Copy in the Marking menu again.
In the Move/Copy dialog, specify the following values:
- Set Move Object to Faces.
- Set Move Type to Free Move.
Dragging from right to left, draw a crossing rectangle to select all the faces of the cylinder and its supporting arm.
In the Move/Copy dialog, click the Set Pivot icon and select a pivot point at the base of the arm.
Click the Set Pivot icon again to confirm that you've finished setting the pivot point. The arrow manipulators dim, putting focus on the rotation manipulator.
Drag the vertical rotation manipulator 25 degrees to the right. You can also type -25 deg in the text box.

Rotate support ribs

For structural reasons, you decide that the support ribs shown here should intersect with the screw bosses. Specify pivot points from which to rotate the ribs until they align correctly with the screw bosses.

Hold down the left mouse button; from the context menu, select the faces to move.
Right-click and select Move/Copy in the Marking menu.
In the Move/copy dialog, specify the following values:
- Set Move Object to Faces.
- Set Move Type to Free Move.
In the Move/copy dialog, click the Set Pivot icon and select a pivot point on the rib.
Drag the rotation manipulator 5 degrees, so that the rib aligns with the screw boss.
Hold down the left mouse button to select the faces of the support rib on the other side of the gear housing.
Right-click and select Move/copy in the Marking menu.
In the Move/copy dialog, specify the following values:
- Set Move Object to Faces.
- Set Move Type to Free Move.
In the Move/copy dialog, click the Set Pivot icon and select a pivot point on the second rib.
Using the rotation manipulator, rotate the second rib 5 degrees, so that it also aligns with the screw boss.

Both ribs now intersect with the screw bosses.

Strengthen the model with an additional rib

After running a finite element analysis, you determine that an end section is structurally unsound because it's supported by only one small rib. Rotate the rib to one side and then use mirroring to create a second support rib.

Hold down the left mouse button and select the two vertical faces of the rib from the context menu.
Right-click and select Move/copy from the Marking menu.
In the Move/copy dialog, specify the following values:
- Set Move Object to Faces.
- Set Move Type to Free Move.
In the Move/copy dialog, click the Set Pivot icon and select the circular outside edge of the model as the pivot point for rotating the rib.
Drag the rotation manipulator to rotate the rib -35 degrees.

Even though you selected only the two vertical faces, the adjoining fillets move with them.
Choose Create > Mirror.
In the Mirror dialog, set Pattern Type to Faces.
Dragging from left to right, draw a selection rectangle around the faces to be mirrored.
In the Mirror dialog, click the Mirror Plane button and select the correct plane for the second rib.
Click OK. A symmetrical second rib appears.

Begin capturing design history

So far, you have changed the design by using direct modeling. In this step, switch to parametric modeling, in which design history is captured. Chamfer a few edges in the model and then see how the recorded design history assists your further edits.

Right-click the Gear Housing component at the top level of the browser and select Capture Design History. The timeline appears at the bottom of the window, showing the model as a base feature.
Select an edge to chamfer.
Right-click and select Chamfer from the Marking menu.
In the Chamfer dialog, set Distance to 1.00 mm.
Select three other edges to chamfer.
In the Chamfer dialog, click OK. Chamfers appear on the four edges.

Notice the chamfer feature that is added to the right of the baseline feature in the timeline.
Right-click the chamfer feature in the timeline and select Edit Feature.
In the Edit Feature dialog, change the distance to 2 mm.
Click OK. All four chamfers change to 2 mm.