Assemble and merge

Create assembly

Now we assemble all the individual parts. In the model tree, expand Assembly, double click on Instances and select all 3 parts. Instance Type should be set to "Dependent".

Checking “Auto-offset from other instances” is also helpful as Bottom Layer A & B have identical shapes and positions and overlap each other, making them hard to distinguish. Alternatively, you can manually translate one of the overlapping parts.

Position parts

Now the parts have to be positioned properly relative to each other. To do this 6 total constraints are needed: 3 translational DOF for each of 2 parts, relative to one fixed part.

Use the face-to-face tool to “mate” faces like you would in SolidWorks (hold down the parallel faces button until another menu appears).

With this tool, you select the two faces you want to mate. the order in which you select faces is important: one of the parts is designated as movable, and the other as fixed. As you add more constraints, you should be consistent about the part you choose to be fixed, otherwise you will create a dependency cycle and get an error.

Here we will treat Bottom Layer A as fixed, and move the other parts relative to it.

The 2 arrows that appear should be pointing in the same direction (click on “Flip” if they aren’t).

Next, set ‘Distance from the fixed plane along its normal’ to 0 and hit Enter. This completes the constraint and the movable part has changed its position.

When mating the bottom face of the Main Body to the top face of Layer A, the arrows will initially point in opposite directions. Click the Flip button to make them point in the same direction.