Making An Assembly

Mechanical Design > Assembly Design

In this page, I want to demonstrate how to assemble some automotive parts together. I'm using parts that I've already have so this tutorial is to be a reference on how to make an assembly. You should try again when you really have some parts ready to assemble.

When making assemblies, you should visualize what type of constraints to be used. It is either to use the Coincidence Constraint, Contact Constraint, Offset, Angle, etc.

There is another way where we can create parts while making an assembly but I'll show it later because I'm in a really tight schedule right now.

Start the Assembly Design Workbench by selecting Start > Mechanical Design > Assembly Design or select New > Product which will automatically brings you to the Assembly Design Workbench. (If it's not, try the first step)

In the Assembly Design Workbench, you'll see a product tree on the top left corner with Product1 as the parent. You can change the name by modifying the properties.



Now right click on the Product1 tree and select Components > Existing Components or select Insert > Existing Components or click on the Insert Existing Component Icon .

A File Selection box will appear and select all the parts to be assembled.



Now all parts have been loaded but all at the same place. Just click on the Explode icon on the Move Toolbar . The parts shall be spread automatically.



We start by fixing the crankshaft using the Fix Constraint or select Insert > Fix and then select on the crankshaft on the screen or on the tree.

To assemble the piston and the piston pin, select the Coincidence Constraint . Then select the outer surface of the piston ring and the inner surface of the piston hole. An axis should pop-up on each cylindrical profile you are selecting that will guide you to select the correct profile.


After the Coincidence Constraint had been established, you should notice the Update Button is active and the constraints on the parts are in dark color. After you pressed the Update Button, the constrained parts should automatically moved to follow their constraints. Then you should see that the Update Button is not active anymore and the constraints are in green color indicating that the parts are in their constrained positions.



Now to make the piston pin exactly in the correct position, we have to insert another constraint between the piston pin and the piston. Select the Coincidence Constraint and select surface 1 and 2 as shown in the figure below.



After that, just push the Update Button so that they move to their correct position.

Then connect the connecting rod to the piston pin using the same method as above. Just try and error to obtain what you want. (the Undo function will be very important).

To move any part to any direction, use the Manipulation Function on the Move Toolbar shown above. After you have selected the Manipulation Function, a Manipulation Parameter Box shall appear and make sure you checked the "With respect to constraint" box. With this, the parts will only move according to their constrained positions.



When using the Contact Constraint , you should know which surface to be involved. After each constraint, try using the Manipulation Function with the "With respect to constraints" checked just to make sure the assemblies and constraints are correct. If the parts are moving just like you intended to, it means that the assemblies are correct. If not, try revise your assemblies. Try to remove the Fix constraint on a part and apply it to other part. Then use the Manipulation Function to check how the parts move.



*I'll make a simple assembly tutorial because I don't feel this is quite helpful. Is it?