Session 4 - Drawing and Refining in ArtCAM

This session was devoted to more refined CAD drawing of ideas developed by the students in initial paper-based sketches to develop virtual 3D models. This involved some accurate measuring and also introduced the students to the constraints of drawing with CAD in relation to the initial sketch and idea. The students needed to adopt a strategy for breaking their 3D idea down into something that could be manufactured from 2D sheet material. Some of the students' ideas involved making a single object, others involved manufacturing more than one component that would fit together to create the adaptive.

Working in ArtCAM

A 3D ArtCAM model on screen

Aim for students:

- To refine their idea so that it can be made into a physical object
- To understand the process of accurately drawing an idea in ArtCAM
- To be aware of how to draw a 2D shape and 3D object and how they differ
- To be aware of the next stage of the process - programming CAM machinery
- To understand the idea of components and assembly in manufacture

Outcome of Lesson:

- A 2D CAD drawing
- A 3D CAD drawing
- Printouts of CAD drawings in various projections

At the CLC the milling machines and other manufacturing equipment are in a separate section adjoining a computer network room to control noise. However, a carefully positioned camera allows students in the network room to see what is going on.

View of milling machine area

Towards the end of the session one or two students were able explore how CAD models are used to programme the computer-aided milling machine.

Learning how to use program the milling machine

Prototypes are often cut into a much softer material such as blue foam or blue wax to speed the process. Final products can be cut into more resistant material, however, this takes longer.

The Denford milling machine cutting a prototype from an ArtCAM virtual model

A CAD package does not yet have the ease of use to allow the same speed of representing an idea as traditional sketching since the user needs a degree of knowledge before using the software effectively. However, ArtCAM does allow a more intuitive approach to CAD than other packages. Developing simple 3D models through CAD/CAM allows the designer/student to check the physical proportions of their design and create a range of prototypes. A physical prototype is also a very effective object to initiate a group discussion and analysis. A 3D form is much easier to investigate than a drawing and is a stepping stone towards the final manufactured artifact.