Home factory: Short-run manufacturing with your 3D printer

3D printing is making innovation possible in many new ways. David Gewirtz shows a short run 3D printing project and explains why his friends think he should be kept far away from power tools.

Let's talk about how 3D printing can make it possible to manufacture products without the barrier of entry previously associated with manufacturing. For small, innovative businesses or for specialized products with small total available markets, this can be transformative.

To understand this, let's take a moment to explore, at a very basic level, what's involved to build a product at volume. Essentially, it's the difference between making something by hand and making something using manufacturing.

The word "manufacturing" is interesting. If you look it up in Webster's, you'll see the definition shown below:

definition-of-manufacturing.jpg

Generally, it's something made systematically or something made with mechanical power and machinery. But the term "manufacture" comes from two Latin elements, "manu," which basically means "made" and "factum," by one's own act or deed. So the Latin "manu factum" means made by hand -- and yet, we today use manufacturing to mean made by a means of production.

The constraints of traditional manufacturing

Historically, production had two characteristics: it was very expensive and time-consuming to set up and make the first unit. Then, because of the volume of production, subsequent units became far less expensive.

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The initial fabricating process was so expensive because first, there was the design and development phase (where models and prototypes had to be made by hand, tested, and for more advanced manufacturing processes, often sent out to machinists to produce). Both the prototypes and the molds or jigs for the production process could take weeks per turnaround, and cost thousands to millions of dollars per cycle.

For objects you expect to produce a lot of, this makes sense. In fact, most of the objects we have in our homes and offices were designed this way, from the push pins we use to stick notices on bulletin boards, to the mice we use to control our computers.

A key concept here is that manufacturing favors volume. It's just inherent in the limitations of the process.

So, now let's think again about building things. If you want a single unit of something, a craftsman can create it by hand. It might take hours, days, or weeks, but one craftsman can produce the object. If you want thousands of something, a factory can do the work.

But what about that middle ground? What if you want 30 of something? At that volume, it becomes far too time-consuming and expensive for a craftsman to build by hand, too expensive to hire a small army of craftsmen to duplicate the original design, and not nearly cost effective enough to justify the relatively measurable investment of traditional manufacturing.

Short run production has always been problematic. Until 3D printing.

Safety considerations

I realized this paradigm shift as a result of a recent project I did for my wife. My wife has figured out something pretty astounding about 3D printing: her husband can build things without causing damage to himself, to others, or to property.

The closest I normally get to power tools is my Dremel and the Keurig coffee maker. Everyone who has ever known me has generally (for good reason) prohibited me from using power saws, welding equipment, plasma cutters, and sometimes even the cutlery one uses in a kitchen to carve a turkey. I am a software guy.

But 3D printing is safe. I have yet to explode anything, blow up anything, short circuit anything, or cause anything to burst into flame after four months of use. This, by the way, is an all-time record.

My wife, therefore, has figured out she can ask me to make things. Not only can I generally do it with my limited shop skills, I can do so without the ultimate result being a 911 call. Yes. It's happened. Nothing is more embarrassing than having three firemen in your house, looking at you like you're a total moron for making a completely stupid mistake.

The high point, when it comes to my craftsman skills, was when I was awarded Eagle Scout at 14. It's all gone very far downhill since then.

Short run project example

My wife is passionate about home and office organizing. She requested that I make a special plastic label holder for those popular cloth bins you see everywhere, so that she knows what's in them without having to open each one up. She had a specific size she wanted, and she wanted it to latch over the bin's handle so it could be attached and removed easily, but not slide off accidentally.

Here they are in use. You can see one of the drawer handles the tags slide over, and she has already labeled a few of them.

3d-printed-label-holders.jpg

I opened up 123D Design and created the model below. It's a simple pair of one millimeter planes separated by a small block, with a semi-circular holder on the bottom that slips over a cloth handle and keeps it securely in place.

makerbot-3d-printer-label-holders.jpg

What's interesting is not the design, but the design process we went through. My wife and I iterated on it five times, each time adjusting size, and tinkering with the space between the planes and the size of the holding gripper.

Before 3D printing, we could have never made something like that out of plastic. If I were a real fabricator, I might have been able to fold steel appropriately to make a holder.

Typically, four or five prototype design and build cycles would have taken something like six months, and cost tens of thousands of dollars. We did it in one weekend, and the filament used cost less than a buck.

Production, too, would have been costly and expensive. That sort of plastic would have to be made out of molds. If done with metal, jig-work would be necessary to make everything match. Large metal presses would stamp out the steel and folding machines would fold it, or plastic would be melted and injected into the molds. That's super expensive, so it favors production runs in the thousands of units.

So far, I've made twelve of those bin tags for my wife. Granted, it takes the MakerBot about 9 hours to produce three units, where large run manufacturing could produce 50 units in a minute.

But we're not in a rush, especially when the entire set my wife wants, which will probably number about 30 when we're done, will cost less than ten bucks. Here they are on the printer.

3d-printing-label-holder-model.jpg

There is a small amount of post processing to get the burrs and stringy things off, but that's a five minute process with a scraper and a sanding block. After that, they're ready to be used.

Suitability for short run production

My one concern was whether these desktop 3D printers were suitable for short run manufacturing, rather than single unit production. I reached out to MakerBot and was told:

The part that wears out over time is the extruder, so if you keep the printer running continuously, you should plan on replacing the extruder after a while. In our testing, the Smart Extruder+ performed consistently and reliably for over 700 hours on a MakerBot Replicator Desktop 3D Printer, which equals 1.44 miles of MakerBot PLA Filament. In fact, over 90 percent of test units were still printing successfully at 1,200+ hours of print time.

The extruder is about $200. Our run will take roughly 90 hours, so we've got a lot of life left in that extruder. Replacing it takes less than five minutes, so even if we did use it to failure, $200 is a tiny fraction of what traditional production would cost.

I've talked earlier about the confluence of crowdfunding and 3D printing mutually supporting a new surge in innovation. The ability to cost-effectively do short run production, with a massively reduced time-to-market, is another example of 3D printing fostering a new level of innovation.

I can't wait to see what people manufacture using 3D printers. If you want to make your own label holders, the design files are up on Thingiverse.

If you 3D print these label holders, or make something of your own, let us know. If you've seen or done 3D printer-based manufacturing, Talk Back below. Heck, if 3D printing blows your mind like it does mine, Talk Back below. Happy printing!

By the way, I'm doing more updates on Twitter and Facebook than ever before. Be sure to follow me on Twitter at @DavidGewirtz and on Facebook at Facebook.com/DavidGewirtz.