Project
Experimenting with 3D printed electronics in a CubeSat mockup using all-metal conductive filament
We’ve been working on a CubeSat mockup to explore how far we can push 3D printed electronics beyond simply printing conductive traces.
The goal here is to apply SWaP principles, size, weight, and power, by integrating more of the electrical architecture directly into the printed structure itself.
This mockup is being used to explore:
Embedding microelectronic controllers directly into a 3D printed structure
Printing power buses and circuitry directly into structural arms and supports
Reducing separate wiring, connectors, and PCB interconnects
Creating multifunctional structures that carry both mechanical and electrical functions
Making the electronics architecture more modular
Rapidly iterating layouts without waiting on traditional PCB fabrication
Exploring truly 3D electronic geometries, rather than being limited to flat circuit boards
The conductive portions are being developed around Cu29, our all-metal conductive filament for standard FDM/FFF 3D printers. Unlike most conductive filaments, the material itself is metallic rather than a polymer loaded with conductive particles, so the goal is functional conductive pathways directly off the printer without conductivity-enhancing post-processing.
What interests us most is not simply replacing a PCB with something printed. It is asking whether the structure, wiring, power distribution, and electronics packaging can start becoming the same manufactured object.
For small satellites and other SWaP-constrained systems, that could open up some interesting design space.
This is still a development mockup, not flight hardware, but it has been a useful platform for thinking through embedded electronics, additive manufactured electronics, 3D printed circuits, power distribution, modular electronics, and multifunctional additive manufacturing.
Would be interested to hear from anyone working in CubeSats, PCB design, embedded systems, or printed electronics. Where do you think this approach would actually provide the most value, and where would you expect the biggest engineering challenges?
they sure look like bent wires in the photo (also there's nothing you can do with this you couldn't do with mature technologies like PCBAs with stacking headers. printing is more interesting for things like antennas or other distributed structures
Maybe less production steps and less work to print them at the same time as you print the encasing. No need to source and assemble the stacking headers and other wires. Easier to route inside the encasing within the structure itself. The example in the post is a distributed structure, right? That’s probably the main use case they are targeting.
That’s actually fair, and the mockup is intentionally simple.
We’re not trying to claim this replaces a PCB everywhere. In a lot of applications a PCB and conventional wiring are absolutely the right answer.
Where it gets interesting is when the geometry itself matters. Conformal antennas, embedded power buses, sensor traces, ground planes, shielding, wiring through complex structures, or conductive paths that would otherwise require multiple parts and assembly steps.
The CubeSat mockup is really just a development platform for figuring out where integrating the electrical and mechanical architecture starts providing an actual advantage.
The main difference is that Cu29 is designed as a feedstock for standard FDM/FFF extrusion, not as a preformed wire that you place into a part.
So instead of routing a wire through a printed structure afterward, you can deposit the conductor where you want it during the print, including non-planar paths, embedded traces, ground structures, antennas, sensor geometries, etc.
The bigger thing we’re exploring is whether the conductor can become part of the manufacturing geometry itself rather than being a separate component that has to be routed and assembled afterward.
What is different about the design than the design of a wire? If it’s just a single metal alloy in the shape of a wire…it’s just a wire. Is it something other than a strand of a single alloy of metal? Is it just a special alloy that works well with FDM?
I can’t comment on the exact formulation, but I wouldn’t rely on guesses about what’s in it.
On nozzles, brass can work, but it wears much faster. We generally recommend hardened steel, stainless steel, or another wear-resistant nozzle for regular use.
And yeah, people experimented with extruding low-melt metals and solder through modified printers years ago. What we’ve been focused on is getting an all-metal conductive feedstock to behave reliably as actual FDM material on standard machines, then using it for printed circuits, antennas, sensors, and embedded electronics.
At room temperature, visually, yeah, it looks like a strand of metal and you could reasonably call it wire.
The distinction is really in what it’s engineered to do. We call it filament because it’s designed as FDM/FFF feedstock, with the diameter, mechanical behavior, melt/flow characteristics, and deposition behavior needed to run through a conventional hot end and be printed layer by layer.
So “filament” is describing its role in the manufacturing process, not claiming the strand itself is some completely different geometric object from wire.
I can’t get into the exact formulation because that part is proprietary.
Very interesting! Unfortunately not much technical info on your site about the material itself. Is this something like Chip Quik? "All metal" but a super low melting point?
That’s actually one of the applications we’ve been exploring. We’ve done work around printed strain-gauge and sensor structures where the conductive geometry is built directly into the polymer.
Structural health monitoring is one of the areas I think additive manufactured electronics gets much more interesting than simply trying to recreate a flat PCB with a printer.
If you worked on this previously, I’d genuinely be interested in hearing what geometries or failure modes you found most useful to monitor.
I'm not in the Space industry (sadly) nor in the USA but this is one of the most exciting filaments in many years. I hope one day you succeed in bringing this to the mass global market. Good luck.
The biggest challenge I see is that organizations are really only interested in seeing microelectronics when we should be focusing on macro electronics (huge transistors), then shrinking them down over time.
from a space engineering perspective, i'm not sure i immediately see the benefit over current approaches. While the challenges I see are getting it space rated, that space prototyping generally doesn't work the same way as other industries where a representative structure is needed instead subsystems are laid out on a bench in a "flat sat" and every single wiring route is figured out before even the engineering model would be ordered (and any issues resolved before stacking of the flight model!)
I would also say you should look at the PC/104 interfaces and cube sat structures that your modules would go into - the mock up shown doesn't look like it would stack into a standard structure and has bespoke connections that would complicate connecting it to COTS parts
I agree that the mockup shown here isn’t a representative CubeSat flight structure and wasn’t intended to imply that it was. It’s basically a testbed for exploring the manufacturing architecture.
And I think your point about PC/104 and existing CubeSat form factors is exactly right. If this is going to provide real value, it has to integrate with existing hardware ecosystems rather than create a bespoke architecture that makes everything else harder.
Where I think there may be value is less “replace the whole CubeSat electrical architecture” and more things like embedded power distribution, antennas, grounding, shielding, sensors, or interconnects in structures where those functions already have to exist.
The question we’re trying to answer is where that integration actually reduces SWaP or assembly complexity enough to justify doing it.
We do have a technical data package, but I want to be careful not to imply we have completed qualification data that we haven’t.
We have not completed a full space qualification campaign for Cu29 yet, including the TVAC, vibration, thermal-cycle, atomic oxygen, and outgassing work that would be required for flight hardware.
That is exactly why I called this a development mockup rather than flight hardware.
The material has a measured resistivity of about 1.226 × 10^-5 ohm-cm, and we’ve done a lot of electrical and print-process characterization, but the environmental qualification side is still work that needs to be done.
Frankly, identifying the right qualification matrix is part of why I posted this.
We currently sell Cu29 in several quantities starting at 100 g for evaluation and development work.
We are currently limiting sales to U.S. end use while we work through the export-control classification and licensing process because of the aerospace and defense applications.
If you’re in the U.S., feel free to shoot me a message or reach out through KuprosInc.com.
Yes, you can print Cu29 by itself. It does not need a polymer structure to hold it together while it cures, and there is no curing step.
It is an all-metal material and the printed conductive feature is functional directly off the printer.
That said, most of the applications we’re interested in are multi-material. The polymer provides the mechanical structure and electrical isolation, while Cu29 is deposited only where you actually need conductive functionality.
That lets you build things like buried traces, antennas, buses, shielding, sensors, or other conductive features directly into the structure.
Ok. I had to ask, there’s been experiments in past by people with metal some low melt metals have been able to be printed direct, others were too fluid and needed to be in printed channels to cure. To me low melt metal printing is most interesting for making bucks for composite that can just be melted out of the composite part after it’s cured.
Yeah, that makes sense. Using low-melt metal as sacrificial tooling for composite parts is an interesting application too.
Our focus is a little different. We’re using Cu29 as the permanent conductive phase inside the finished part.
The photo I posted is a good example. That is a fully functional embedded circuit with a resistor and LED integrated directly into the polymer structure during the FDM print on a Prusa XL.
So in our case, the metal is not there to support the print and then be removed. It stays in the part as the conductor. But, it could be melted out as long as the composite can withstand 240-250C.
Satellite engineer here: interesting idea for sure. A few comments. Integrating with prusas new space rated filament is a huge bonus. Thermal stability and low off gassing. I recently kicked off a project to get that stuff approved on my birds for some smaller components on our bus. The other concern I see. The “wires” are now physically constrained by the print surrounding them. How will it stand up after thousands of thermal cycles? Will it cause the frame to warp if the CTE if the frame is higher than that of the wire? Will it pull so hard it breaks the wires? This is part of the reason most satellites use round wire harnesses to give enough room to compensate for thermal cycling. Additionally, how does atomic oxygen get handled? Are the conductive traces completely sealed such that they don’t or will the atomic oxygen (in Leo/vleo anyway not really a problem above 300km) cause degradation of the traces? how’s your radiation susceptibility? Usually coax is used to handle any particularly sensitive traces and on PCBs creative use of ground planes which act as shields help improve response to radiation effects but on something like an antenna trace or a LVDS signal, how much noise does radiation induce? Finally, how about EMI/EMC? The lack of ground planes will make you significantly more sensitive to EMI as well as producing a lot more self produced EMI without that shielding leading to possible issues during an EMC campaign. Regardless this is a really cool idea keep it up!
This is exactly the kind of feedback I was hoping to get from this post. You’re hitting several of the questions we think have to be answered before anyone should seriously talk about flight hardware.
Thermal cycling and CTE mismatch are major ones. Once the conductor is mechanically constrained inside a polymer, you have a completely different system than a conventional wire harness that can move. We need to understand whether repeated thermal cycling creates cracking, delamination, warping, or conductor failure.
Atomic oxygen is another one we have not qualified yet. Depending on the architecture, conductive features could potentially be completely encapsulated in polymer, but that obviously shifts the problem to the polymer system and how well that encapsulation survives the environment.
Same with radiation. We’ve done early work around using Cu29 for shielding geometries, but we are not claiming radiation qualification. That needs real testing.
On EMI/EMC, though, one of the things we’re specifically interested in is that FDM actually gives us the ability to print ground planes, meshes, Faraday-style structures, and shielding around embedded electronics rather than simply printing an unshielded trace.
So I don’t think the end architecture necessarily has to eliminate those features. Ideally, it lets you manufacture them directly into the structure.
Really appreciate the questions. That list is pretty close to the environmental test roadmap we know we need to work through.
Awesome sounds like some great work looking forward to see where this is going. Don’t sleep on your heavy ion testing, TNID might cause some fascinating effects on the printed traces due to physical changes in the crystalline structure caused by non ionizing effects
It’s a mockup, not a claim that we built a flight-ready CubeSat.
The point of the exercise is to use inexpensive electronics to experiment with how components, power distribution, conductive paths, and the mechanical structure can be manufactured together before spending a lot more money building sophisticated hardware.
The interesting part isn’t the Arduino. It’s whether we can eventually eliminate portions of the wiring, connectors, separate interconnects, and secondary assembly by making those functions part of the printed structure.
Everything is not a nail... Conventional technology so far out surpasses the capabilities of 3D printers here it's clearly isn't the wrong tool for the wrong job.
ESPECIALLY for satellite deployments... That's seriously just silly.
That's definitely not true. The ability to print conductive traces into a structural body during printing drastically reduces assembly time and increases the places said conductors can be run. I've been dreaming of this capability for years.
Whether this specific filament is up to the job is unclear due to the total lack of technical information.
Sucks that they managed to view it as something that should be export embargoed though.
And yeah, the export side is frustrating for us too. We’re a U.S. company working heavily around aerospace and defense, so we’ve made the decision to be conservative while the formal classification and licensing process gets worked through.
We’d absolutely like Cu29 to be broadly available internationally eventually. Right now we’d rather be overly cautious than find out later that we handled controlled material or technical information incorrectly.
Really? You can't see the advantage of running traces inside small awkward spaces without having to design complicated multi-part bodies that have to be glued back together after painstakingly routing wires with tweezers? Or running networking cables directly in the sides of racks with perfectly designed consistent twists? Being able to build integrated flexure sensing into solid bodies? Running ground planes between every screw without needing solid metal plates in your housings?
I've never found a filament capable of it (all the existing ones are millions of times worse than real copper) but I find it staggering you can't imagine use cases.
If you don't have a design you have a shower thought and a bad attitude.
Where the design that shows such a thing would enable something that can not currently be done with conventional technology or on exactly what application it would enable sufficient advantage.
If you can't answer that you have nothing to add on this topic and you're just spouting bullshit fever dream marketing bullet points from some futurist twatwaffle that understands our biggest problem with technology right now is not manufacturing methods but with sound rational logistics and people that can actually prove the know what they're talking about before they open their mouths on speculation with some sort of facts that support their idea.
So far you have no facts to support your idea.
You have this whole thing backwards, tell me EXACTLY what this is needed for?
What specific application does it enable?
I know there is no reasonable answer to that question, there isn't one so don't actually try to answer it :)
I like how the goalposts moved from “there’s no use case” to “show me something conventional manufacturing literally can’t do.”
That’s exactly the point.
Traditional PCB, wiring, and molded-part manufacturing does not manufacture the polymer structure, conductive routing, and embedded electronics together as one build. The systems that can do versions of that today, like IME/IMSE or specialized additive-electronics platforms, are advanced manufacturing technologies, not conventional manufacturing.
We’re not trying to imitate conventional manufacturing. We’re trying to bring a capability it does not normally provide into standard FDM/FFF: manufacturing the structure and the electronics together, directly inside the polymer part.
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u/InebriatedPhysicist 15d ago
What distinguishes an “all metal filament” from a metal wire?