How We’re Building a Robotic 3D Printing Factory

A manufacturing startup’s journey to cut costs and take on injection molding.

Jonathan Schwartz
Mar 15, 2017 · 12 min read

Co-written with Max Friefeld.

Manufacturing is one of the most fundamental, yet inaccessible building blocks of modern society. It is how we produce the overwhelming majority of parts and products we use both intentionally, and inadvertently. “Manufacturing”, unlike “making”, can be described as the process of repeatedly producing a physical object at scale. Over the past couple centuries we’ve transformed our methods of manufacturing from the human-first approach used to make textiles during the Industrial Revolution, to the assembly line structure introduced by Henry Ford, to modern just-in-time production invented by Toyota, to today’s imminent robot revolution.

Voodoo Manufacturing is a Brooklyn-based startup that uses commoditized 3D printing technology to manufacture plastic parts and products. Our unique approach to manufacturing enables us to produce anywhere from 1–10,000 parts in less than 2 weeks at injection molding prices. That last part is critical — being able to cost-compete with injection molding is what makes us a viable alternative for producing a given part. Up until today, 3D printing has remained a technology used primarily for prototyping or high-value part production (i.e. custom medical devices or rocket engines). However, we are pushing it in a direction that makes it available for actual end-use part production for more common applications.

Beyond 3D printing specifically, we believe in a digital future for manufacturing where lead times are short, iteration cycles are fast, products can be customized, and runs can start small and scale instantly. Our goal at Voodoo is to alway stay focused on those core goals so we achieve that future.

We believe in a digital future for manufacturing where lead times are short, iteration cycles are fast, products can be customized, and runs can start small and scale instantly.

One of our printer banks in our Brooklyn factory. We have a total of 160 printers on our 2,000 sq-ft floor that are used for part production on a regular basis.

A New Hope

(Or How We’re Going to Take on Injection Molding by Cutting Costs)

As a result of our efforts over the past 2 years, we’ve found a comfortable niche within the market for sub-10,000 unit runs of plastic parts. The most popular applications for our service include marketing and promotional products, and then hardware and engineering components. However, the fact remains that the majority of today’s world-wide part production is for runs of greater than 10,000 units. Therefore, to make our manufacturing method a more viable alternative to injection molding, we must offer the ability to scale beyond 10,000 units and still compete for price.

Injection molding may be used to produce millions of units of a given part, so for the purpose of setting an achievable goal that would still have significant impact, we decided we need to hit 100,000 units as our next milestone. In order to do that, we’ll need to cut costs by an order of magnitude. When my co-founder and I first realized this, we looked at each other in a slight horror. After taking a minute to think it over, he said “If Elon Musk can improve the cost of traveling to Mars by 5,000,000%, we can improve our costs by 1,000%, right?” [1] We then began the task of figuring out how the hell we could cut costs that much (equivalent to a 90% reduction) over the next 3 to 5 years [2].

“If Elon Musk can improve the cost of traveling to Mars by 5,000,000%, we can improve our costs by 1,000%, right?”

Our costs today come from three main areas: material, machines, and labor. To reduce our overall costs by 90%, we will need to reduce each of these cost areas by 90%, or an equivalent combination.

A graph showing the relationship between the effective unit cost for a hypothetical part using injection molding vs. 3D printing. By reducing our costs 90%, the point at which injection molding becomes more cost effective (“cost-intersection” point) gets pushed to a higher number of units.

Material is the easiest cost to reduce. It’s just a matter of time until 3D printing material costs approach the cost of raw plastic pellets used by injection molding factories. This is mainly due to the fierce competition between the enormous and growing number of material suppliers. As larger incumbents continue to enter the market, this cost will continue to drop further and further. If that doesn’t get us low enough, we could also eventually vertically integrate and produce our own material in house, eliminating the margin added on by an intermediary supplier.


Next up is machine cost, which determines how much we have to charge for each hour of a printer’s time. This cost is a result of the amortized machine price over the expected lifetime of the machine at a given rate of use. That means our levers for this cost are the machine price, lifetime, utilization, and output. We figure machine costs will stay about the same since we expect the technology to improve overtime (yes, you can buy a cheap laptop today, but many of us spend more for better machines). However, given our expected growth, we assume we’ll be able to reduce the machine costs by buying in bulk and getting manufacturer discounts.

As for machine lifetime, we don’t expect this number to ever change significantly. Even if we could extend the lifetime of the printer, one of our fundamental hypotheses is that underlying technology will improve rapidly and so we’ll want to update our machines every few years, regardless of whether they are still functional.

Lastly, machine efficiency is based on production speed, scrap rate, and equipment utilization (this is known as OEE — “Overall Equipment Effectiveness”) . We expect that as high-end technology trickles down to the low-end, we’ll see scrap rates decline and build speeds increase. Considering machine utilization, today with 160 printers and 5 full-time factory employees working 8 hours/5 days a week, we are at about 40% utilization. The question now is how do we push that as close to 100% as possible while minimizing the cost of doing so? This leads us to our last cost category: labor.

One of our fundamental hypotheses is that underlying technology will improve rapidly and so we’ll want to update our machines every few years.


Today, much of our production process consists of manual labor. From changing-over printer material between jobs, to harvesting finished prints, to packing and shipping, our factory is still very much run by humans. Reducing labor costs has been a secondary focus of ours over the past 2 years, since even with a somewhat inefficient process we were able to compete on price with low-volume injection molded parts. But more than either of the previous two cost categories, labor will be the critical path to efficiently scaling capacity while reducing costs.

Cutting labor costs comes down to eliminating unneeded, wasteful parts of a process, and automating the remaining manual tasks that are necessary to make and ship product. This is the game that every manufacturer is starting to play. It’s becoming clear that it will define not only the way we make things for the foreseeable future, but also a new world economy in which manual labor will be almost entirely eliminated from the majority of factory floors. This is both an exciting and scary prospect that I’ll touch on later, but for Voodoo, the need to automate labor became clear as not only the key to our future success, but as a necessity for our survival. And so, we began on a path to identify the first slice of our production process where we could introduce automation to increase our capacity while maintaining or lowering costs. Enter Project Skywalker.

Use the Force, Luke

(Or How We Built a Robot-Operated 3D Printer Cluster)

There are many parts of our current production process that require a human. Some are trivial and repeatable, requiring little in-the-moment decision making. Others are abstract and ever-changing, necessitating skillful problem solving for successful results. When deciding what part of our process to attack first we considered 1) what the easiest part to automate would be, 2) what automated part would have the biggest impact on our labor requirements, and 3) what would prove, through a literal or representative lens, that our business could scale well beyond where we are today and become a manufacturing giant. Eventually, it became clear we would first try to automate the “harvesting” step of our process.

Harvesting is what we call the manual process of removing a printer’s build plate (the substrate onto which the printer prints) after a completed build, and replacing it with a new clean build plate ready for the next print. Today, our factory employees spend significant time harvesting printers — approximately 10% of their working hours. That doesn’t even include wasted printer time after a print has finished but before someone harvests it and starts the next print. Aside from the opportunity to reduce the time we spend on a trivial, low-value-added task, and to keep printers up and running for longer, harvesting is a perfect and almost quantifiable task that we felt confident in being able to automate with speed, accuracy, and precision.

Collaborative robots provide an approachable device with the promise of safe human interaction.

Knowing the task we wanted to automate, we choose the Universal Robots UR10 robotic arm as our method for automation. The UR10 provided a low-enough price point paired with surprising precision and payload capacity sufficient for the target task. Most attractive, however, was the collaborative nature of the robot. Traditional robotic arms are large, expensive, powerful machines that require intense safety protocols and path planning to use. Collaborative robots, on the other hand, provide an approachable device with the promise of safe human interaction. Rather than build a factory with caged-off areas and hazardous possibilities, we preferred the idea of a friendly workplace where continuous and spontaneous improvement and interaction are default.

With arm in hand, we constructed the rest of the demo system, consisting of 9 3D printers mounted to server racks [3], a track where the robot could deposit harvested plates to eventually be collected by an employee,

and a custom-built plate “hopper” that would feed new, clean plates to the robot as needed. Once all components were in place, we were able to collaboratively plan the paths to and from all 9 printers, the plate track, and the plate hopper. Lastly, using our internal software, we were able to establish communication between the printers and robot. We could notify the arm when a print finishes and on which printer, and receive notification of when the arm successfully placed a new plate on a printer, thus signaling the automatic start of a new print. After solving many edge cases and unforeseen problems, we eventually arrived at the finish line and built what we know to be the first-ever robot-operated 3D printer cluster [4].

The next morning, we returned to find over 30 successful prints for an actual production job we were working on at the time. It was magical. One of our employees described it as a sort of “turbo speed boost”.

After running the entire system for a number of cycles while we were present, we finally worked up the courage to run it overnight, without any adult supervision. The next morning, we returned to find over 30 successful prints for an actual production job we were working on at the time. It was magical. One of our employees described it as a sort of “turbo speed boost”. For the given set of 9 printers, we were able to increase output by 3x compared to the production printers sitting in our factory, solely because we could start prints throughout the night versus only during the standard 8-hour shift we currently run. Even though we shouldn’t have been surprised by the results, we all had this strong realization of how much of a game changer this would be.

Extrapolating from the 9-printer cluster, we now estimate that a single arm will be capable of tending to approximately 100 printers within our factory. Using a robot to automate purely the harvesting step of our process would increase the current 40 printers/employee ratio to approximately 400 printers/employee. We also estimate that all in, each deployed robot arm will have a payback period of 3 months. Project Skywalker was a massive success, and all of Voodoo is now excited for the day we deploy it within our factory at full scale.

A Galaxy Not So Far, Far Away

(Or How Robotic Automation is Going to Change the Manufacturing Industry and Affect the United States)

Having now gone through the exercise of automating labor within our factory, we’ve gained valuable insight into what automation means for not only us, but the greater manufacturing industry.

Manufacturing companies will be able to compete on price once again, and create entirely new services that redefine how things are made.

Over the past few decades, manufacturing has left the United States for overseas factories that could provide comparable services at much lower costs. This was mainly due to the lower labor costs abroad. However, all manufacturing companies are now looking towards automation as a way to cut costs, improve quality, and increase output. Yes, this includes companies in China.

The United States is still a manufacturing powerhouse today, just for a different set of capabilities, and not for production that requires significant human labor. In fact, the US now produces 85% more products than in 1987, but with only two-thirds the number of workers [5]. With all the talk these days about how manufacturing and manufacturing jobs are going to return to the US, it’s important to understand that the truth is we’re never going to see a return of how things used to be, or the same manufacturing jobs that we used to have. Rather, with new automation technologies there will be new opportunities. Existing manufacturing companies will be able to compete on price once again, and new manufacturing companies will be able to innovate and create entirely new services that redefine how things are made. Industries will blossom, and there will be new opportunities for re-education, re-training, and employment. From all this, we’ll likely see a net increase in manufacturing jobs in the US over the next decade [6]. Foreign manufacturing companies will also open up factories within the US so they can be closer to both the companies they produce for, and end customers. This all will result in lower costs, faster innovation cycles, and higher-quality products.

At Voodoo, we see automation as more than just a way to cut costs — it’s the only way we’ll survive to ever be a large company that employs hundreds if not thousands of people. The path we walk is one that many companies have already started down. Those who choose not to will fall behind and be faced with the choice of changing or fading. As a startup taking on a massive and deeply entrenched industry, automation is our primary weapon. Automation is in our DNA.

Watch the full Project Skywalker behind-the-scenes video here.

About Voodoo Manufacturing

Voodoo Manufacturing is a Brooklyn-based startup that’s on a mission to change the way we manufacture. Learn more at


[1] In SpaceX’s Mars mission plan, Elon Musk outlines that to make travel to Mars viable, he’ll need to “improve” the cost by 5,000,000%. Watch and download the presentation here:

[2] As a startup, setting very long-term goals won’t help us in the near-term, so we decided it was imperative that we figured this out within a relatively short timeframe.

[3] We commonly tell people that our factory looks more like a server farm than a traditional factory, so we were excited to use actual server racks for the first time to house our 3D printers. In our factory, we use custom built 80/20 racks, but will probably switch to server racks during our next expansion.

[4] We consider a “robot-operated 3D printer cluster” to be the use of robotic automation to continuously and independently operate 3D printers in order to produce actual finished parts. A few other companies have release concept “demos” but none that we would consider close to being ready for a production environment.

[5]Manjoo, Farhad. “How to Make America’s Robots Great Again.” The New York Times. 25 Jan. 2017. Web. <>

[6] This is true for the United States, however, for other countries that house many of today’s manufacturing jobs, a much different situation will most likely unfold in which they observe significant job loss. This is an incredibly important problem that needs to be solved to avoid massive unemployment and economic recession.

All text and images Copyright © 2017 Voodoo Manufacturing, Inc.

Voodoo Manufacturing

Voodoo Manufacturing is a robotic 3D printing factory that…

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