I have been thinking quite a bit about 3D printing lately. Maybe that’s because I’m now surrounded by 3D printed prototypes at work. Maybe it’s because the news in the tech world is full of stories about products and services related to 3D printing. All of this has lead me to two conclusions:
- In the short to medium term 3D printing will be something that companies use to provide customized goods to consumers, not something that consumers use directly.
- 3D printing won’t take off for in-home manufacturing until a printer can build something like a toaster
A 3D printer is an incredibly powerful tool for prototyping. In the hardware lab at the office we have a couple of Dimension printers, a laser cutter, a PCB mill, a Vinyl cutter, and a fairly complete set of power and hand tools. With those tools, a few McMaster-Carr and Digikey orders, and enough assembly time we can build a prototype of just about anything. A dizzying array of goods has come out of that lab and let us try out things in a few days to a week that would have taken us a few months to a year if we had tried to do the same thing ten years ago.
The problem is that the output of the printer requires additional off the shelf parts and significant assembly time to turn an ABS structure into something functional. This is where I think the toaster is a useful mechanism to talk about.
The pop-up toaster is arguably the simplest appliance in your kitchen. And yet it is also filled with components that are beyond the reach of 3D printing today. (You can learn more than you ever wanted to know about how a toaster works here.) Here are several challenges that toasters present for 3D printers:
- The whole device is heat-resistant. Toasters heat to about 300 degrees Fahrenheit, but the melting point of ABS plastic is only 221 degrees. Clearly printing the toaster body out of ABS isn’t going to work.
- The power cord of a toaster contains both conductive elements and insulating elements. There are also insulating elements scattered around inside the toaster. Extrusion printers can handle the insulating elements, but not the heat resistance. Binding printers (sintering or EBM) can handle the conductive elements, but only print one material at a time so they can’t combine the conductive elements with the insulating elements in one object.
- “A toaster’s heating element usually consists of Nichrome ribbon wound on mica strips.” Nichrome is actually used in extrusion printers to heat the plastic. I can’t find any reference to either it or Mica being printable, and that would definitely require multiple materials in a binding printer.
None of these problems are insurmountable. Several 3D printers can already print in multiple materials. They just all happen to be different kinds of extruded plastic. Eventually those printers will figure out how to include metal in their parts. Heat resistance is probably a bigger challenge given how the printers work, but in theory they could use materials with even higher melting points so the resulting products could handle 300 degrees without a problem. And the list of materials that can be printed is growing every year. Eventually these problems will be solved.
That brings me back to the first conclusion, however, because I don’t think those solutions are going to come from the low-end printers you can afford to put in your house. Figuring out how to print conductive and insulating materials in the same batch is a hard problem. Heat resistance is a hard problem (for extrusion printers). Printing new and exotic materials is hard problem. These are the sort of thing that researchers are going to chew on for a while, then expensive first generation commercial implementations will need to be built.
As MakerBot eats away at the low end businesses of Objet and Dimension these bigger companies will move further up-market and add some of these higher-end features. Eventually MakerBot and its ilk will get those features too, but that is going to take a long time, probably ten or more years. In the meantime, the only printers capable of printing “advanced” devices like a toaster will be those that cost tens or hundreds of thousands of dollars. Price alone will keep these printers out of the hands (and garages) of individuals for a long time.
The only people who will be able to afford the next generation of toaster-capable printers are companies that use that capital investment as part of their business. That includes hardware labs that use these as tools for prototyping, but also mass-customization companies that build iPhone covers or print MineCraft levels today. These companies can charge a premium for their products because of the customization so they can amortize the cost of the printers (and learning how to use them) over thousands of customers. They will also be the primary market for companies like Dimension and Objet, so those printer providers will have no reason to drop their prices to a level normal people can afford.
One last random thought before I end this meandering post: The printers that we’re running in twenty years will bear about as much resemblance to today’s 3D printers as my Nexus 4 bears to my first computer (a TI 99-4/A). They will be a combination of binding and extrusion, or something we can’t even imagine now. They will include many elements of a pick-and-place machine to include complex semiconductors in the resulting devices. And, once their utility reaches a certain point, their prices will be in free-fall. Eventually the future of 3D printing is bright. I just don’t think it’s going to happen overnight.