I did an interview last year for EE Times Japan with former Wired editor Chris Anderson who arguably did more than anyone to hype up 3-D printing.
Perhaps I caught him on an off day but he noted:
--There are still big limitations on what kinds of materials can be used by 3-D printers
--Volume manufacturing is still very much the game of big companies because it involves many kinds of machines and processes that are not networked and not available to the average person with a desktop 3-D printer.
I agree 100 percent. The idea that 3D printing is going to displace a lot of the current manufacturing technology is misguided. But that said, I think we can all agree that it will be used for many applications and has tremendous potential. Plus, it's pretty cool too.
"Specifically, GE is developing a metal nozzle for its LEAP jet engine. They will use 3D metal printers to produce the nozzles, which will be lighter in weight due to an advanced design producible only on 3D printers."
3D printing is perhaps a misnomer, but I don't think we should let that limit our thinking.
Hasn't everyone wondered why you can send only certain types of "product" over the Internet? Used to be just text, then it became graphics and essentially finished documents (minus the paper), then sound and motion pictures. So why the limitation? Why do I need to depend on parcel post to have a vacuum cleaner sent to me from a web site? Why can't the web site e-mail me the vacuum cleaner as it sends me a finished document that I can print out at home?
Conceptually, it's because we have technology that feeds paper in to a printer, but we don't yet have the next step that feeds ANY raw materials into a "printer," to manufacture any product, based on instructions received from anywhere else. So while I can order a book from Amazon, I can also, at least in principle, "manufacture" that book at home, by feeding raw material (paper) and instructions (say, an Acrobat file) into a printer, and create the entire product that way.
For now, the "raw material" is limited to paper (2D printing) and plastic (3D printing). Conceptually, it doesn't need to be so limited. Computer aided manufacturing is used to build all manner of products, and I think of 3D printing as merely the first step to doing CAM in the home. For Star Trek fans, 3D printing is another step toward that "replicator" device, where you place your order and out comes the product.
I agree we should not limit our imagination and the emailable machine/object is a great idea.
But does it differ conceptually from an emailable text file that tells you which lego bricks to put where...or an emailable map which shows the shop on your local high street to go buy a conventionally-made machine/object from.
The point of my article I guess was that everyone seems to think because the CONCEPT is extremely fascinating - be it self-replicating or emailable machines -- they also think that 3D printed manufacturing is juat around the corner and that the self-replicating or emailable machine delivered by 3D printing will be just as good as one made using conventional manufacturing.
There are a lot of engineering challenges between the concept and the reality
For example would you want a 3D printed part made today to be used as a replacement part inside your bicycle gears or automobile engine? Even if it met the dimensional specification perfectly it would not have been approved for use and would expect that its plastic construction would not be mechanically strong enough.
I think it is different from e-mailed instructions on how to assemble Lego blocks, in the sense that 3D printing lets you manufacture your own Lego blocks. So 3D printing is really a logical "next step."
As to the material, again, why limit ourselves to plastic? Plastic is merely the "next step," beyond paper. Plastic happens to be easier to mold that other raw materials are, but there's no conceptual reason to think that 3D printing can't produce steel gearsets.
Ultimately, one shouldn't even be dissuaded by the idea that feeding iron to a 3D printer is ridiculous. No reason to assume the 3D printer has to be at home. We can also take our instruction file to a 3D printing facility at the closest shopping mall and have it spit out the finished product. Just as we might do to get professional quality photographic prints made, by taking of JPEG files to a photofinisher.
We are beginning to 3D print metal parts now. But the fundamental problems remain, due to the nature of the 3D printing process. A 3D printer does sintering, applying successive layers of the material used, and heating it to fuse them.
Even with metal, you hit limitations in the kind of metal that can be used, and the heat required for fusing. (The heat requiresd may well make this a "Kids, don't try this at home" exercise.)
Conceptually, it's a bit like the difference betweem casting and forging iron. Cast iron simply isn't as strong as forged iron, and neither approaches steel. What if the part you want to make really needs to be made of steel?
A lot of things people might like to do with 3D printers are likely to remain the province of CNC milling machines, which sculpt the necessary part from an existing piece of metal that is hard enough for the intended usage.
There are companies that print in metal right now! They tend to use a different method than the typical "hot glue" style printer you see right now. Look at Shapeways for example, you can choose for your item to be printed in a variety of plastics as well as stainless steel, silver, and ceramic.
These are all interesting points. 3-D printer is a bit of a mystery for me for long time.
For one, as one of my friends pointed out, it is very good to reproduce "one of a kind" thing. Think about an antique table that you just bought, but a leg is missing. 3-D printer would come in handy.
For another, I believe that it could work in a larger production scenario, too. I used to work for a consumer electronics company. I seem to recall that one of the big investments for those manufacturers was always in making a "mold" for their next product that needs to be mass produced. 3-D printer could take some pressure off of that mold cost.
Thanks for the article Peter and I agree with your points, but thought I'd add this recent example.
Whether the average Joe can expect to buy the system AR uses is anyone's guess, but it already makes significant improvements in cost and schedule, so it will certainly stick around. Imagine what only a few generations of improvements to the system will do for reducing the system's cost and complexity.
Early users or investigators should never say never, but for a couple reasons I find 3-D printing limited. The primary limitation is that the printing process is an additive one where a maleable substance is deposited in precise locations. This is the opposite of most manufacturing processes in which material is precisely removed from a billet by various machining operations. The latter lends itself with few changes to an almost unlimited palet of materials from plastics to the hardest metals. I think power and speed must also be factored in somewhere. A lathe can remove a quarter of an inch of steel from a 4 inch long shaft in a matter of minutes, powered by a 1 HP motor. A 3-D printer would have to melt (assuming it possible) the amount of metal required to build the shape. Add to this the fact that most of the time heating the metal to melting point would drastically alter its characteristics.
I can see 3-D printers useful for building a T-Rex skull on the kitchen table and perhaps making paterns for castings but I'm not going to throw away my broom while waiting for a vacuum cleaner to appear in my paper tray.
Well, as to your second sentence. CAD drawings can be immediately converted to Numerical Controled Machine language which can operate many different machine tools. That's the easy part. But loading the stock, provisioning the machine with the appropriate cutters, etc. is considerable overhead for a one off item. Assuming a 3-D printer could process the same raw material (right now unlikely) a single or small production quantity might be less costly, overlooking completely the energy equation.
I'm not sure about structure strength. Crystalline structure is not much affected by proper machining and temperature control. It seems that would be hard act to follow for any type of deposition fabrication.
I also wonder about the ability to scale a 3-D printer. In most things one size doesn't fit all. I'll guess that both processes will be eventually be joined at the hip and both processes will be used to their best advantage.
I agree with most of what you've said. It has always bugged me when people comment on how a 3d printer can print itself. Especially when you're talking about additive plastics. The most important parts of the machine are the hot nozzle(extruder) and the stepper motors. Neither of which can be printed as a functional unit right now.
I was amused by the following statement though.
"Also, in the general case a machine that could print itself could only make smaller copies of itself -- just as a mother makes a baby. I am excluding special topological cases, such as a donut-shaped machine that could extrude a sausage-shaped daughter-machine designed to then curl up to form a full-sized repeat of the mother-machine."
This only holds true if you also require that machine to assemble the product. I own a 3d printer and have actually printed several things that, when assembled, are of a larger volume than the printer itself.
This is a very interesting topic. I suppose one awkward point for 3D printing is what happens if a particular piece got botched in the middle. I suppose it would have to be scrapped? Otherwise, you'd have to pick up exactly where you left off. Wouldn't that automatically generate a flawed interface (like a defect) between the previous and restarted printing portions?
I absolutely agree that 3D printing won't let machines reproduce. (That may happen, but not because of 3D printing.) The most impressive use I've seen to date was by a heart-surgeon who transformed a CAT scan into a 3-D model of the heart upon which he planned to operate. It enable him to see exactly what he would find inside the heart itself in a way that a 2D image just can't do. At that point, I started believing a lot of what I'd previously dismissed as hype.
I think the 3D printing has brought the manufactruing to home just like the desktops brought the computing to home some 30 years ago. So tomorrows kids will not just assemble the DIY kits from the blocks provided but will have the freedom to create their own building blocks. 3D printing is a good tool for prototype building and also a tool to build small actual objects. I have seen a news where there is a plan to construct a full size house using a special 3D printer. So what 3D printers will do in the near future is best left to one's imagination. The only hitch is the material handling !
Looking behind the hype, what is left ? A new tool.
And - as it is with every tool - there are hobbyists fiddling around with it and there are others using it to the extremes. An - well known - example: a solder iron is a versatile tool. You can even use it to make pictures on wood. In the expert's hands it can be used to produce the most complicated and advanced electronics. (Though you might choose more sophisticated soldering tools :) )
And one of the latest 3D printers in the - extended - hobbyist budget is a real photolithographic printer: no longer fiddling with thermoplasts. - - - Time will show how these tools are developing. I'd expect new applications to be found.
BTW: in the far, far past there have been some "unorthodox" plotters having wheels instead of some kind of flatbed. Applying this principle on 3D printers would - to some extend - overcome the current object size limitations.
On the other hand the "subtractive tools" (vulgo: CNC lathes and milling machines) are becoming more and more affordable too. Though currently this is not in the public focus.