Re-use pattern, Sectioning, Save management

We mentioned re-use pattern when we discussed Product structure tools and constraints, however we did not see it practically. Also, there are other concepts worth understanding with regards to an assembly. Let's see them one by one. 

Re-use pattern

Re-use pattern let's us make use of pattern used in part to instantiate and assemble parts easily and quickly. Consider the plate shown below where one of the hole was created originally using hole command, while rest were simply patterned. Now, in an assembly, we are required to put bolts in all holes. To do this, we would only assemble one of the bolt in its place using constraints like offset, coincidence of the axis etc. And that is what is shown below, we assembled one bolt in one of the hole.

One bolt assembled with plate

Creating top-down assembly, Copy and paste, Assembly features

How to create a top-down assembly in Catia?

Making a top-down assembly is same as making a bottom-up assembly, to the extent that you would need to apply the constraints in the same way as you applied during the bottom-up assembly. However, in case of the top-down assembly it is required that we start with an assembly file and make all parts from within that particular assembly file, unlike in case of bottom-up assembly, where we called already modeled parts and assembled them. 

For the top-down assembly, we would create a three part assembly. By creating this assembly in the top-down manner, we would learn how to effectively navigate between product / part environments and modify parts and assemblies from within the single document. The drawings for these parts are present below. We have kept the parts simple for the sake that you can practise easily.

Top-down assembly - Assembly and Parts drawing

Creating bottom-up assembly

To create a bottom-up assembly, you would require already modeled parts saved in a folder. If you have not made the parts or do not wish to make them, you can download the parts using this link. These parts have been made using Catia V5R21, so you can use the same release or higher to work with these parts.

Assembly file, Product1 created

Product structure tools, Constraints, Move toolbar

Creating an assembly requires use of tools that are specific to the Assembly design workbench. Creating bottom-up assembly or even the top-up assembly requires knowledge of these basic tools. These tools are present under Product Structure tools toolbar, Move toolbar and Constraints toolbar. Let's first study these tools and then we will move to creating an assembly. 

Product structure tools

Product structure tools toolbar has the tools for creating new part or product files from within the workbench environment which you may do in a top-down assembly process. It also has tools for bringing in the parts that have been already created for the purpose of assembly. In addition, it also has some other relevant tools.  Below you can see all the tools that are present in this toolbar. Let's see these tools one by one.

Product structure tools toolbar

Assembly design workbench

What is an assembly?

An assembly or a product, in general, refers to the collection of different parts and assemblies, that together perform a required function. For example, an engine that comprises of piston, crankshaft, camshaft etc. is an example of an assembly. In Catia, an assembly is basically a document with .CATProduct extension that stores information about the collection of different components (parts, assemblies etc.) that the assembly constitutes, and all these parts are held in position / assembled together at their respective working positions. So wherever you open this assembly document, it displays all parts and assemblies that the document constitutes.

Assembly shown with specification tree