Affordable 3D printing: New materials, new horizons
Cheap 3D printers have had a bad rap. Seen as toys for enthusiasts, most work by squeezing melted plastic filament through a thin nozzle (Fused Filament Fabrication, or FFF), producing what is often dismissed as tat.
The reality is far more exciting: these devices are revolutionising the world of product development, are set to educate a generation and are home to some of the most innovative developments in the 3D printing world.
The most obvious riposte to those who dismiss consumer 3D printers as playthings are the many crowd-funded projects that start out their manufacturing run using 3D-printed parts. It's not hard to see why: 3D consumer printing offers enticingly low costs for short-run manufacturing.
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The first generation of affordable 3D printers needed as much loving attention as a British motorcycle. Spanners, allen keys, bits of wire and digital callipers were all tools of the trade, helping to unblock and align printheads, or level the print bed. That's now become a lot easier, as has the essential but often overlooked 3D software that runs the show.
Enter Adobe
Low end 3D printing received a significant boost in January this year when Adobe added 3D printing support to Photoshop CC. Until then 'slicers' — the software that converts 3D models into three-dimensional printhead movement — have mostly been written by enthusiasts or limited to the rather basic software provided with printers.
The quality of a 3D-printed object depends as much on the slicer used as it does on the hardware. It manages building supports — bits of plastic not in the design that are needed to cope with parts with overhangs. Slicers also control subtle but vital details like exactly how much and how fast filament is retracted when the head moves to a new location. Enthusiasts can spend as much time fiddling with slicer parameters as they do with the printer itself.
Adobe's offering is a big step forward. It intelligently thickens the walls of models to add strength just where it's needed, and cleverly builds with the absolute minimum of support. Unfortunately even Photoshop CC 2014 — the second release with 3D printing — still only supports seven brands of 3D printer. There is a 'draft' online guide to creating a custom XML file for your own printer, but it lacks basic information such as how to import that XML into Photoshop. Adobe itself offers the bare minimum of support: when we asked, customer service demonstrated that they had no idea how to import the XML either. Adobe, one supposes, expects the 3D printing community to add new printers. They would if they could, but they can't, so they haven't.
More usable, more affordable
3D printing is getting easier and cheaper. In 2012, 3D Systems launched the user-friendly £839 ($1,425) Cube printer, and 2013 saw a raft of even lower-cost self-calibrating 3D printers that claimed to work straight out of the box.
The most promising are yet to ship: at $299, the M3D, planned for launch in January 2015, promises to be a cheap and usable FFF printer. Similarly, the $499 RigidBot has the unique promise that its print area can be expanded just by adding longer rods. The RigidBot is due to ship to non-investors in August 2014.
But at $100 the Peachy photolithographic 3D printer — if it ships and works — will beat them all on price. It works completely differently, using a liquid polymer resin hardened by a laser that's steered by a PC's audio output. This video explains how it works.
And if those aren't enough, there are over 120 other 3D printers trying to launch via crowd-funding sites.
At this point, it's perhaps worth mentioning MOTA's "high-performance and affordable personal 3D printer" as a cautionary tale. The Kickstarter project launched on 7 July, with the promise of an October 2014 launch at a recommended price of $599. Early investors were offered discounts at $99 and $299, both of which quickly sold out. However, there was also much negative feedback over MOTA's proposed use of proprietary filament cartridges ($30 each) rather than 'generic filaments' of ABS or PLA.
As a result, on 10 July, a message appeared on MOTA's Kickstarter page from co-founder Kevin Faro, the crux of which was: "We have learned a great deal from your comments in the last few days. And they tell me we need to go back, work harder, and find a way to reduce the price even more as well as make the technology more open. So we are cancelling the project until we can deliver on that promise."
So if you see a tempting Kickstarter offer, be aware that things may not always go according to plan.
Education, cubed
There are other barriers besides cost. Designing in 3D is far from intuitive, and education is the obvious route to massive takeup in the next generation — something that needs to be fixed. Fortunately thanks to Minecraft most 14-year- olds are skilled in 3D design, and there are already several packages that convert their creations to 3D-printable models. For more advanced work, Trimble Navigation's free Sketchup Make software (formerly owned by Google) offers a simplified introduction to 3D design, while the open-source Blender 3D offers a professional range of features.
Together these applications offer a marvellous training ground for the product designers, animators and games creators of the future. Even the youngest kids can get started; the Printeer 3D printer — another yet-to-ship Kickstarter project — enables any child who is able to scribble on a tablet access to the technology for $549. Perhaps 3D design skills will be the next technological gap separating a generation of teens from their parents.
New 3D printing materials
The last couple of years have seen massive growth in the range of materials that can be used by consumer 3D printers. Until recently there were two options: Acrylonitrile Butadiene Styrene (ABS) and Polylactic Acid (PLA). ABS is the plastic of Lego bricks; it's tough, but hard to print with. PLA, which is usually made from food starch, is biodegradable and easy to print with, but crumbles to dust over a long period.
Recently, new materials have become available for affordable 3D printers such as Taulman's Nylon, which is both strong and resistant to damage by solvents like petrol. High-strength and high-temperature composites that mix carbon fibre and PLA can be had from Proto-Pasta; these combine the advantages of the well-understood print properties of PLA with the strength of carbon fibre. Proto-Pasta also offers a high-strength polycarbonate-ABS alloy and a high-temperature PLA. Or, for the dinner table, you can now obtain food-grade polypropylene from German Reprap.
Building more complex models is getting easier too. Support structures that more easily dissolve away after printing are possible, thanks to High Impact Polystyrene (HIPS) filament that dissolves in solvents like limonene or dipentene.
New 3D printing horizons
Other brand-new 3D printing functions are becoming available. Since 2012's carbomorph, an electrically conductive feedstock developed by the University of Warwick, a raft of commercially available products, such as Makergeeks' conductive carbon composite ABS have made it to market. At 10,000 Ohms/cm, it's more a way to build sensors such as water-level detectors or switches than a replacement for wiring or metal connectors. However, it does make possible a range of more functional 3D-printed objects.
There's also been a big expansion in the range of aesthetic choices: thermochromic plastics change colour depending on the temperature (think Global Hyperolor T-shirts of the 90s), while Taulman 3D's t-glase (short for Tough Glass) offers excellent transparency and, like conventional PET (Polyethelyne Tetrachloride), is relatively easy to work with. Less plasticy finishes are now also an option: Kai Parthy of CC-Products has created Laywood, a composite containing 40 percent recycled wood, and also Laybrick, a chalk and co-polyesters composite with a sandstone-like finish.
Moving towards the mainstream
With costs decreasing and usability improving, together with the ability to print at ever finer resolutions in a fast-growing range of materials, affordable 3D printers may well repeat the 1980s success of the home computer as they too begin to usurp the older and much more costly 'professional' competition.