Early desktop printers were horrible. For the price of thousands of dollars one got lo-res dot matrix printouts on paper that had tractor-feed holes punched into the margins. It wasn’t pretty, but those early models paved the way for high-resolution, low-cost laser printing.
Today’s 3-D printers are similarly crude. They all use Fused Depositon Modeling (FDM) technology and are essentially robotic hot glue guns. Fortunately, a new generation of higher-resolution, faster, and more reliable machines are starting to come to market.
This new breed of printer use Stereolithography (SLA) technology, utilizing light instead of heat to make models. How? A high powered light source hardens a cross section of light-sensitive liquid plastic. The machine then raises the build platform a smidge and the process is repeated. It’s very dramatic — models look like they are being pulled from a puddle of goo.
This pioneering technology brings three much needed improvements to home based 3-D printers:
1. Higher Resolution Models, Built Quicker
Parts made on SLA systems are much higher resolution than prints from FDM machines which have bumpy, ridged surfaces. They aren’t quite as polished as injection molded parts, but are almost as good as professional grade mills.
Also, since the light hardens the plastic simultaneously, the only factor impacting print speed is the height of the object. With FDM printers, speed is determined by the amount of plastic needed to fill in a cross section, which slows the process considerably.
2. More Complex Geometry is Possible
Trying to print a complex sphere like the one above on a FDM machine would lead to nothing but pulled hair and wasted plastic. The SLA construction opens up new, richer design possibilities.
3. Translucent Materials
Because of its capacity for high-resolution and the nature of the chemicals used in the process, SLA models can be translucent. They won’t be optically clear, so you won’t be printing yourself new specs any time soon, but the see-through look brings a new palette of options for designers.
Yes, There Are Downsides
SLA-based 3-D printers do have drawbacks. The biggest red flag is that no established companies are selling these kits yet. They’re being developed by enthusiasts (read: no dedicated customer service when you’re in desperate need of help).
Also, they’re expensive, retailing for $1,999 to $3,375. While that’s not too far a stretch from the top-of-the-line MakerBot, it’s vastly more than a $500 BuildrBot.
The ‘consumable’ resin is also more expensive. A few pounds of plastic for an FDM machine costs $50-80, but a similar amount of light-sensitive resin will cost $120+ dollars.
Early-adopter limitations aside, SLA based 3-D printers are much closer to the state-of-the-art in the professional market and will produce parts that have the polished look of mass manufacturing.
Ready to learn more? We compiled a handy list of SLA printers on offer:
Cost – $2,375 for the kit, $3,375 fully assembled
Build Size – 3? x 4? x 8?
Layer Height – 0.004?
Special Features – The B9 Creator boasts the biggest build area and a pretty boss industrial design.
Cost – $1,999
Build Size – 1.1? x 1.7? x 7?
Layer Height – 0.005?
Special Features – The MiiCraft has a pump to automatically distribute, collect, and store resin and a “hardening chamber” to cure prints after the initial build. Be warned though, the build size is small with a challenging aspect ratio.
3-D Home Made
Entrepreneur Junior Veloso is a major contributor to the SLA 3-D printing community and launched an IndieGoGo campaign that raised $60,000 in 24 hours. Unfortunately, he has seemingly pulled the plug on his impressive looking machine. No word on commercialization, but subscribe to his blog for future updates.
DIY 3-D printing started out as a humble open-source project, but in less than five years has become a big business with a plethora of kits, packaged systems, and amazingly low prices. With these new SLA based kits, the pace of progress doesn’t look to be slowing any time soon.