Jay Leno, the ubiquitous and entertaining but abrasive (?) talk-show host uses his ‘Big Dog Garage Team’ to maintain his fleet of very old cars and motorbikes. Recently his team had to fabricate a feedwater heater for his 1907 White Steamer. An innovative approach was done using a 3D scanner to create a detailed digital model of the part; this was then fed to a 3D printer which made an exact copy in plastic (over 30 odd hours) which was then machined from solid metal.

A Rapid Drop in price
This type of rapid prototyping technology has dropped dramatically in price over the past year or two. For example, an industrial 3D printer has fallen from $100k to less than $2k for use in a home environment (and there are kits available to build 3D printers for ~$500).

3D Printing
The 3D printing is done in an additive way. A modified ink jet printer deposits successive layers of material until the 3D object is built up. No wasteful scrap generated from the traditional approach of milling/grinding/boring and cutting. The material used is usually a thermoplastic ($30/pound) or polycarbonate. Metallic powders have been used as well.

One of the critical aspects is the 3D software and this can be done with a variety of packages ranging from the free-ware Google’s SketchUp or Blender. Alternatively Autodesk and Solidworks are available – but at a price. Autodesk have even released a zero-cost program called 123D Catch that can turn multiple photos of an object (at different angles) into a 3D printing file. It should be noted that the scanning process is still an imperfect process so some cleaning up is required.

The Revolution
Suggestions are that personal manufacturing is currently going through the same revolution the PC went through in the 1980’s. Based on the massive growth and enthusiasm in this area; this certainly seems true. This is where the engineering entrepreneurs can go berserk creating new ideas in their garage and then ‘building them’ almost immediately.

The uselessness and expensiveness of it all?
Obviously, there will be comments about the uselessness and expensiveness of this technology as to actual cost of each item created (compared to a mass produced item) and the real application to the every day person. But the same comments were made about personal computers in the seventies and eighties. And I can clearly see incredible opportunities for the engineering professional in prototyping and creating new parts which would have been enormously difficult, time consuming and expensive to produce in a factory.

When you hear about technologies such as 3-d printing, Arthur C. Clarke’s comment comes to mind: Any sufficiently advanced technology is indistinguishable from magic.

Yours in engineering learning

Steve