Here we continue our 3D printing feature by looking at where you can find 3D models to print and how to design your own.
3D printing Resources
Whether you buy a 3D printer, assemble one from a kit or use the services of a 3D printing company, before you can start printing you need a 3D software model. There are various ways of getting hold of 3D models for all levels of expertise.
First of all, just as you can find photographs of pretty much anything online, the same is true of 3D models. A lot of these libraries were set up for people who wanted to manipulate three-dimensional images on-screen but many are also suitable for 3D printing. To start, though, we suggest that you turn your attention to those online resources that cater specifically for the growing demand for 3D models for printing.
We’ve already seen that 3D printing company Sculpteo’s site has a large library of 3D models but this is just the tip of the iceberg. Perhaps the biggest online resource is the Thingiverse which is owned by Makerbot. Described as “a place for you to share your digital designs with the world”, the Thingiverse is also the converse, namely a place for the world to share their digital designs with you.
According to Makerbot, the Thingiverse currently holds designs for 36,000 ‘things’ and reports that the number of items is growing rapidly. To help you find your way around this huge collection of 3D models they are grouped into nine categories – art, fashion, gadgets, hobby, household, learning, models, tools, and toys & games.
An alternative that requires minimal work, yet still allows you to create something that's your own, is to use one of the online utilities provided by some 3D printing bureaux. Sculpteo is well ahead of the game here in providing utilities for printing customised iPhone cases, geometrical models, 3D text and much more.
Similarly, Makerbot has just launched the Thingiverse Customizer that lets you customise 3D designs in your browser. As an example suggested by Makerbot, “you can take a snowflake that you find on Thingiverse, bring it into the MakerBot Customizer, determine how many points and stars it has, and then print that custom, one-of-a-kind item”.
If you want to create something truly original from scratch, you’ll need to turn to a 3D CAD (Computer Aided Design) package. While this isn’t for the faint-hearted, if you persevere there’s every chance that you’ll succeed in making your own 3D models that you can view and manipulate on screen and ultimately turn into a real world object.
Alternatively, if you want to print a real-world object, you can take lots of photographs of it and use software to stitch them together to automatically generate a 3D model. For step-by-step instructions on how to do that take a look at How to print 3D models.
3D file formats
On thing to be aware of in choosing or creating your own 3D models is the question of file formats. Just as there are several file formats for photographs, of which Jpeg is the most common, there are several formats for 3D models and you should choose a format that is compatible with your printer or which your chosen 3D printing service can accept. However, if you find something that you like that’s in the wrong format, you’ll probably be able to convert it yourself. MeshLab, for example, is a free package for editing 3D models but since it can both import and export nearly all the common formats, you could easily use it for format conversion.
A final thing to bear in mind is that while even the cheapest 3D printers are suitable for producing decorative items and curiosities of various types, you might be disappointed if you need something with structural strength.
Certainly 3D printers have been used to create very durable objects for use in engineering projects but this can’t be guaranteed for selective laser sintering printers working with plastics. This was demonstrated recently by The Verge who tried printing customised cases for the Lumina 820 following Nokia’s decision to release the 3D designs of its own case.
The cases were printed by two bureaux who both expressed doubt that it was appropriate to 3D print a design that had been intended for conventional plastic manufacturing techniques such as injection moulding. In particular they had misgivings that parts of the case were thick enough for selective laser sintering. This view was confirmed by the fact that weak spots on both cases broke when attempting to remove the cases from the phone.