[Exclusive] Phaetus, the hotend brand — and Runice, the company behind it: the founders on their 100M RMB raise, the brand family, and Japan

Hi, this is YuTR0N.

This is an exclusive interview with Phaetus and its parent company, Runice.

In June 2026, Runice (Jiangsu Runice 3D Technology) — a global supplier of 3D printer hotends and nozzles — announced a funding round of nearly 100 million RMB. A raise of that size going not to a printer OEM but to a company built around core components and system solutions: what does that tell us about where this industry is heading?

If you buy printer parts often, or you’ve been part of the Phaetus beta tester program, you may already know the name. Runice runs a family of brands — Phaetus, FusRock, Arkfly and Bulber — and ships to more than 90 countries and regions. Phaetus itself was born in 2019, which makes this its 7th anniversary. And if you’re thinking you’ve never used a Runice product: that’s fair, because most of what they make is sold B2B. Those customers sell on, sometimes B2B again, sometimes B2C. If you have a 3D printer at home, there’s a decent chance some part of it was machined in a Runice factory.

※ This article contains affiliate links. If you buy through them I earn a commission, which goes straight back into playing with 3D printers.

Founding story (Wu Jin)

Q. You’re reported to have worked in Japan’s semiconductor industry before founding the company. What did you do there, and how does that experience show up in how you build things today?

Before founding Runice I worked at companies in Taiwan, Singapore and Japan. In Japan I was mainly in process development. That experience shaped me deeply, because it was where I really understood what manufacturing is — not “making” a product, but making it well, consistently, over and over. Focus, sharpening precision to the last micron, and keeping a permanent respect for quality. I learned all of that there.

Q. When did you first encounter a 3D printer? Do you remember the first machine you touched?

In 2012, at a university, I saw a RepRap printer for the first time. What struck me most was that the machine could print some of its own parts. The idea of a machine making machines left a very strong impression. Unfortunately I was only observing that day — I didn’t get to operate it myself.

Q. In 2013 3D printing was still completely niche. Why start with components rather than complete machines?

Most people assume we did components from day one. We didn’t. At the beginning we built complete machines. But the market hadn’t arrived yet, the machines didn’t sell, and cash flow kept getting tighter. To survive, we started developing core components like nozzles, and built up technology, customers and reputation bit by bit until we got to where we are today. Looking back, that pivot was the most important decision in Runice’s history.

Q. Tell us about the first product and the first customer. When and where did the first overseas order come from?

The first product was a single nozzle. The first customer was a DIY user I met online — sadly we lost touch afterwards. The first overseas order came from South Korea, in the winter of 2013. The office didn’t even have air conditioning back then; a customer who came to visit was shivering. Looking back, conditions at the company were rough, but everyone was full of expectation for the future.

Q. What influence did RepRap and the open-source community have on Runice in its early years?

The printer I saw at my very first encounter with 3D printing was a RepRap. You could say RepRap and the open-source community are the origin point of Runice entering this industry. Most of our early customers were DIY enthusiasts from open-source communities around the world. They didn’t just buy and use the products — they sent us improvement suggestions and helped us iterate. It was the trust, feedback and support of those early users that carried Runice through its hardest period. Being open, creating together, respecting the user’s voice — those became principles we still hold today.

Q. What was the most dangerous moment in 13 years? And on the flip side, which order or encounter became the turning point?

The hardest moment wasn’t when the company nearly went under. It was when the industry shifted and we couldn’t pivot fast enough, and let a major growth opportunity slip. We had actually built a relationship very early with a customer who later grew into a leader in this industry — but in the end we failed to catch that window. It has stayed with me ever since, and it made me believe more strongly that the biggest risk to a company isn’t competition; it’s missing the moment to change yourself.

What genuinely changed Runice’s fate was an OEM opportunity given to us by a European customer. After that we entered the international market properly, and gradually built the R&D and manufacturing organisation we have today.

Q. Are there companies or people you admire as a business leader? (Inside or outside the industry.)

I’ve always admired Apple and Toyota. From Apple I learned the importance of an uncompromising product experience; from Toyota, lean production and continuous improvement. I also have deep respect for Steve Jobs, because he kept insisting on making the best thing rather than the thing that would sell.

Q. Do you still look at drawings and prototypes yourself? What’s your decision-making style?

I still look at drawings from time to time, and I check important samples with my own eyes, especially anything genuinely innovative. I believe in first-principles thinking — rather than being bound by rules of thumb, I like to go back to the problem itself. In the end I care about results. Whether something actually got done matters more than the reasons along the way.

Q. How would you describe Runice’s culture in one line? What do you ask most of your people?

We’ve consistently held to “put the customer’s success at the centre, and value the people who get things done.” What I care about most isn’t how clever someone is. It’s whether they take responsibility, see things through to the end, keep growing, and create value for the customer and the company.

Q. How many printers do you have at home or on your desk? What have you printed personally lately?

One at home. My daughter and I print little ideas and toys together now and then.

Q. Which of your own products are you most attached to, and which competitor’s product made you think “they got us”?

If I have to pick one, Dragon. It was Phaetus’s first real signature product, and the one that made a lot of users aware of us. Of course there are plenty of excellent products in this industry worth learning from, and we always keep an open attitude.

The raise, and the business (Wu Jin)

Q. Your June announcement lists “core technology,” “digital manufacturing” and “global brand” as uses for the ~100M RMB. Which comes first, and what will you actually do with it?

Core technology R&D always comes first, because technology determines a product’s competitiveness and a company’s long-term value. Digital and smart manufacturing is how we turn that technology into products at high quality and high efficiency. Global brand building is how more customers come to know and use our technology. The three support each other, but everything is anchored on technical innovation. What Runice is aiming for isn’t to be a component supplier — it’s to become one of the world’s leading platforms in core 3D printing technology and system solutions.

Q. Why do you think investors put money into a components specialist now? As multi-head and multi-material printing spread, how does the value of a component change?

I think what investors valued wasn’t a “components company” but a company becoming a foundational technology platform for the industry. Until now, competition in 3D printing has been concentrated on complete machines; from here the axis moves to core technology and system capability. With multi-head, multi-material, multi-process and AI developments, a single 3D printer is no longer a simple mechanical device — it’s becoming a complex smart manufacturing system.

In that shift, the value of components changes too. What will be asked of us is not an individual part but a complete system solution. Take the extrusion system: it’s no longer a conversation about a hotend or an extruder in isolation. It only delivers real performance when it works in concert with motion control, material properties, sensors, software algorithms and thermal control.

That’s why we believe the future competitiveness of a component maker lies in defining systems rather than making one product, and in empowering an entire platform rather than supplying one part. That’s the direction Runice is going. We do have the capability to build complete machines, but we chose to focus on core technology and system solutions — supporting printer makers worldwide in shipping faster, better, more competitive products, and pushing the whole industry forward together.

Group and brand structure (Wu Jin)

Q. What is Bulber Innovation Lab researching right now? Are next-generation approaches like induction heating or liquid cooling on the table?

Bulber Innovation Lab is focused on core technologies for the next generation of FDM additive manufacturing: extrusion systems, thermal management, motion control, materials, smart sensing. New technologies like induction heating and liquid cooling are within our research scope. That said, we don’t do new technology for its own sake. What matters is whether it genuinely solves an industry problem or improves the user experience. If a technology can make 3D printing more efficient, more reliable and more widely adopted, we’ll keep investing in it and exploring it.

Q. Where do the brand names come from — Runice, Phaetus, FusRock, Arkfly, Bulber?

Runice combines “Run” and “Nice.” Run stands for keeping moving, for innovation and execution; Nice stands for excellent products, a good experience, open collaboration. We want to be a company that keeps running and, at the same time, creates value for customers and feels “nice” to partners. Only when the customer succeeds does Runice truly succeed — that’s what we believe.

FusRock combines “FUS” and “ROCK.” FUS is Fusion — the fusion of materials, technology and innovation, and a nod to the melt-extrusion process at the heart of FDM. ROCK is stone: a symbol of high performance, reliability and durability. We want FusRock to be both a byword for high-performance composite materials and the embodiment of an idea — that material innovation can give printed parts rock-solid reliability.

Phaetus is a modern reworking of a name derived from Hephaestus, the Greek god of the forge. It stands for engineering spirit, craft obsession and relentless innovation — exactly the brand philosophy Phaetus has held to. That’s why we set the slogan as “Supreme Pursuit.”

Bulber — Bulber combines “Bulb” and “-er,” symbolising the people who light up the future with wisdom and creativity. Bulber.com is a co-creation platform for 3D printing developers, enthusiasts and professionals around the world to share knowledge and build together. The value of technology is maximised through sharing and collaboration — that’s the founding idea behind Bulber.

Arkfly — Ark plus Fly. A brand dedicated to build platform module technology and products for 3D printing, aiming at breakthrough print platform technology in “another form” that lets users fly past existing constraints.

Q. What’s the revenue split between OEM and your own brands? How do you handle situations where a customer’s machine competes with your own brand?

OEM/ODM business is roughly 80%, own-brand business roughly 20%. We do have Phaetus as an in-house brand, but we’ve never once thought of ourselves as competing with printer brands. If anything we’re the ones doing the empowering: we break through on core components and deliver the results to the whole industry. The better our customers’ machines get, the bigger our value becomes. It’s a relationship where both sides grow together.

Technology and manufacturing (Donald)

Q. In developing Liber for the Rapido X, what was the real bottleneck in pushing past 100 mm³/s? How many prototype rounds, and what was the biggest failure along the way?

The bottleneck was at the corners of Liber’s splitting flow path, and the uneven pressure gradient within the chamber volume. The differential pressure between the nozzle inlet and outlet fluctuated momentarily, and flow wouldn’t stabilise. Feedback control based on flow sampling is heavily affected by that fluctuation, and with static, fixed PID parameters there was no way to compensate dynamically.

The prototyping process ran to 32 design iterations in CFD fluid simulation and 23 rounds of physical samples (structural parts and embedded PCBs). As for the biggest failure — at first we suspected the control side and kept optimising the PID loop. But even after optimisation, roughly 10% variance in limit flow rate remained between samples. The root cause we finally traced it to was machining tolerance on the flow path’s inner diameter. After that we brought the dimensional tolerance of the inner bore under control, and Liber’s print quality finally stabilised.

Q. The flow rate race looks like it’s hitting a ceiling. What’s the next axis of differentiation — quietness, maintenance-free operation, material range, or something else?

The first axis is material compatibility (the highest barrier to entry, and the biggest source of premium). Flow rate is just one metric among many. The industry’s real problem is handling and adapting to filaments with different properties. Even under the same material name, differences in colour and additives change melt behaviour and flow significantly. Printing red and black filament stably on the same extrusion system already requires sophisticated adaptation work. The same goes for handling both flexible TPU and fibre-filled PA. Pushed far enough, the essence of multi-material capability is demand for multi-functional applications.

The second axis is quietness, and unattended, maintenance-free operation for industry (a must-have for production-floor users). Today’s high-flow machines are noisy and generate vibration when motors run fast, which is hard for home users to accept. On top of that: hotends that don’t clog, nozzles that don’t get wrapped in plastic, unattended part removal from the build plate, automatic calibration, one-touch printing. Smartness and simplicity — that’s what ordinary consumers require of an FDM printer, and we’re reminded of it constantly.

Q. Even among 0.4 mm nozzles, performance differs. What is the quality that doesn’t show up on a spec sheet — surface roughness, concentricity, tolerance? What do you measure, and how?

The essence is the difference in geometric tolerance of the nozzle’s micro-bore. Three things matter most. First, concentricity of the micro-bore. Concentricity between the outlet bore and the filament bore directly determines internal flow resistance, and has a large effect on whether filament extrudes straight down. Concentricity between the outlet bore and the outer taper face directly determines the positional accuracy of the outlet after nozzle calibration, and therefore print accuracy itself. Second, the roughness of the nozzle’s inner wall. A rough wall makes plastic stick and stagnate, affecting flow resistance inside the path; worse, long-term stagnation causes carbonisation and eventually clogging. Third, bore diameter tolerance. Diameter tolerance is ±0.01 mm, and that dimensional consistency directly determines print consistency when switching between multiple hotends mid-job.

For inspection: bore concentricity is measured on a Keyence optical imaging micro-bore concentricity system, scanning the full length in segments, controlled at micron scale according to product specification. Inner wall roughness is measured with a Mitutoyo internal roughness gauge, sampling two pieces per shift. Bore diameter is checked with a high-magnification toolmaker’s microscope and an image measuring system.

Q. Is inspection 100% or sampled? What are your defect rates?

We vary the inspection strategy by characteristic. Critical dimensions and tolerances (anything with a CPK requirement, for example) get 100% inspection on automated equipment — image recognition, contact-type 2.5D programmed measurement and so on. For something like the outer diameter of an interference-fit section, the non-conformance rate detected and screened out in-process is about 4%. General dimensions and tolerances are sampled, with an in-process non-conformance rate of about 2%.

These are numbers detected and removed inside the manufacturing process, not post-shipment defect rates. And ultimately, part quality is built in by the manufacturing process itself and by the quality methods upstream of it — DFM, PFMEA, SPC.

Q. What makes tungsten carbide hard to machine? What’s the real yield?

It’s extremely hard — comparable to the hardness of cutting tools — so it can only be machined with special tooling and processes such as diamond tools or laser machining. As a difficult-to-cut material, material removal is slow and tools wear extremely fast, so dimensional tolerances drift easily. On top of that, tungsten carbide is brittle: entry radii and thin sections around the bore mouth will chip microscopically under very little force. Some of that isn’t visible to the naked eye and only surfaces under operating temperature and pressure, turning into a defect. By our internal standard, overall finished-part yield is about 80%.

Industry structure and OEM (Wu Jin)

Q. The funding announcement mentioned supplying several major manufacturers at home and abroad, and coverage of 90+ countries and regions. Is there a supply case you can talk about specifically?

Because it touches on the details of customer relationships, please allow me not to name names. As an example: for one brand’s multi-head printer, we co-developed the hotend and extrusion system with them. We were involved across the whole process, from early technical direction through prototype validation to mass production delivery. I think the reason a customer lets us in that deeply is that they value our R&D capability in core components like hotends and extrusion, and the stability of our volume production and delivery.

Q. What’s the most unreasonable request you’ve ever had from an OEM customer?

We rarely describe a customer’s request as “unreasonable.” This industry moves fast, and requests are often not unreasonable so much as ahead of the curve, or genuinely challenging. If I have to pick the toughest: cases where we were asked to go from design to mass production in an extremely tight window. For example, compressing a three-month development schedule into six weeks — and still delivering at volume. We’ve had several of those, and the customer was under market pressure of their own.

When that happens we do two things internally. One is to tell the customer clearly which steps can be accelerated and which cannot be compromised for quality’s sake. The other is to stand up a dedicated rapid-response team and run technical review, prototyping and testing in parallel rather than in series. We made the delivery — but the cost was the whole team working late day after day, and several weekends gone. You can do that once or twice. Make it the norm and it’s bad for quality and bad for the team’s health. So afterwards we ran a retrospective with the customer and helped them build more reasonable project plans. Honestly, we take those “unreasonable” asks as a sign of trust in Runice: they believe we can do what others can’t.

Q. The announcement also mentioned growth in aftermarket demand — users buying third-party hotends that outperform the originals. With proprietary standards and first-party lock-in spreading, how do you see this market’s future?

First, something we should acknowledge as fact: closed ecosystems are an unavoidable stage on the way to industry maturity. Printer brands like Bambu Lab have, through deep software-hardware integration, genuinely made 3D printers feel like appliances — out of the box, stable, dependable. Those brands do place some limits on third-party parts, through methods like RFID filament identification and firmware authentication.

Second, though, “limited” is not “eliminated.” Space for third-party components still exists, and is in fact expanding. The global market for 3D printing parts and accessories is expected to keep growing. Performance upgrades are a must-have need: first-party parts usually aim for “good enough,” while third-party parts can deliver “better.” For example, under our internal test conditions, our silicon carbide (SiC) nozzle has shown up to roughly 7× the wear resistance of a hardened steel nozzle. The Conch series of hotends supports major machines including Bambu Lab and Creality. What printer brands do is “0→1” — getting more people started with a 3D printer. What we do is “1→N” — helping people who are already printing to print better. The two aren’t in opposition.

Third, our strategy: don’t become an adversary, become a co-creator of the ecosystem. Technology comes first. Phaetus has already developed 36 print head and hotend solutions for overseas markets, supporting operating environments up to 450°C. Next, ecosystem collaboration of the “developer program” type — three-way co-creation involving printer makers and community developers. With Creality, for instance, we released the “DXC2” extruder built for the K2. Rather than routing around printer brands, we build the ecosystem with them.

There are two survival logics in this industry. One is the build-to-print machine shop: you make exactly what the drawing says, and the customer can swap suppliers any time. The other is technology-driven: study core components like hotends and extrusion more deeply than the printer makers themselves, then empower those customers with the results so they can build better products. Runice chose the second. We’re not a competitor to printer brands; we’re closer to an external R&D partner developing core technology alongside them. Even as things close up, the third-party parts market won’t disappear. It will simply move upmarket — from “cheap compatible” to “what the professionals choose.” This market is wide enough for printer brands and third-party component makers to grow together. And we’ve spent 13 years preparing for it.

Q. You’ve dealt with clones and counterfeits for years. How do you handle imitation of your own products today?

Honestly, our technology is genuinely easy to imitate. All the core components exist as physical hardware, so the cost of taking one apart, measuring it and copying it is extremely low. Our thinking about imitation is simple. Don’t expect to be able to stop it. Make it impossible to catch up.

First, we do file the patents and trademarks worth filing. That’s the baseline, and at minimum it gives us a legal means of defending our rights. Second — and this is the important part — keep generating new generations and maintain the technology gap. Silicon carbide, EndCoat coating, high-flow solutions: every year we ship new materials and new processes, generation after generation. While imitators are chasing the existing product, we’ve already moved on to the next generation. That’s how we keep a technical distance that’s hard to close. In the end, the core of dealing with imitation isn’t only defence — it’s to keep running. To evolve fast enough that imitation loses its commercial value.

FusRock (Wu Jin)

Q. Engineering-plastic filaments (PA-CF, PPS, PPA and so on) have appeared from every brand at once lately. How will FusRock approach this space?

PA-CF was the first product FusRock brought to market. We’re now rolling out high-performance engineering plastics like PPS and PPA as well. We’ll keep expanding the engineering-plastic line-up, but we’re not chasing sheer number of materials. What we care about is making these materials genuinely stable and dependable on an industrial floor. To do that we pair them with Phaetus’s high-temperature extrusion systems and co-develop material, hardware, process parameters and application validation as one package, so users get a complete system solution. Our goal isn’t to sell a lot of filament. It’s for users to actually master engineering plastics and achieve industrial-grade applications.

Background and role (Fly)

Q. What’s your own background? How did you end up joining Runice, and how did you meet Wu Jin?

I’m a UI/UX and brand designer. We met in the early days of Wu Jin’s company, when I did the brand design for his 3D printer brand. In 2019, when he launched the Phaetus brand, he asked me in, and I took part in building Phaetus’s brand design from zero. To put it bluntly, back then Wu Jin was my client. Over the five years I supported the Phaetus brand, I saw first-hand how uncompromising he is about technology, engineering and user experience. From something as big as defining brand strategy to something as small as settling a single performance parameter, he doesn’t let any detail slide. Once he got talking we’d regularly go until morning. In 2025 he formally invited me to join Phaetus, and I was certain that following a leader with that kind of see-it-through spirit couldn’t be a mistake. And so Wu Jin went from being my client to being my boss.

Q. What does “Phaetus brand owner” cover? Product planning, marketing, sales channels — how far does it go, and how do you divide roles with Wu Jin?

I oversee the running of the Phaetus brand as a whole — marketing, sales, and the execution of product projects. Wu Jin has his own read on where the technology and the market in this industry are heading, and gives us strategic direction on technology, product and market.

On the Phaetus brand (Fly)

Q. In one line, what value does the Phaetus brand want to embody?

What Phaetus pursues is ultimate print performance, long-term stability, and broad compatibility. Delivering upgrade products where users can actually feel the value — that’s our mission. Ultimate performance: extreme performance isn’t an accident, it comes from outstanding engineering and the Phaetus spirit. Durability and stability: stability isn’t just a result, it’s a standard — we run extreme testing to build products that are accurate and dependable through very long operating hours. Universal compatibility: designed to fit major machines, so you can upgrade quickly by dropping it in and draw out the full performance potential.

Q. The Dragon series made the brand’s name. What stands out most from the development period and the reaction after launch?

Before Dragon came out, almost every all-metal hotend on the market had one fatal weakness: they were too delicate. A levelling error and the print head would crash into the bed; try to swap a nozzle during routine maintenance and the heatbreak would snap. The Phaetus development team designed a proprietary torsion-resistant structure and thoroughly optimised heat conduction. It survives twisting, it survives impacts. And on top of that it opened up an experience that hadn’t existed before — changing a nozzle with one hand.

Q. How did Rapido spread through the Voron community? What was the proudest moment for the brand?

The Voron community at that time was going through a speed revolution. The print head solutions of the day could no longer meet what those builders wanted in terms of print speed. Rapido arrived with sharp technology — up to 75 mm³/s flow, a torsion-resistant structure allowing one-handed nozzle changes, a cylindrical ceramic heater unit — and the geeks recommended it to each other furiously on Discord and Reddit. After that, a lot of printer manufacturers adopted Rapido as the factory-standard print head.

Q. Who decides product names — Dragon, Rapido, Conch, Conweb — and how?

The workflow around the Phaetus brand is very open and very geeky. Rather than a product manager or marketing person deciding, as at many companies, we pull in every department — R&D especially — and run brainstorming with no limits. When the discussion reaches the level of defining a brand name, it often ran until just before sunrise the next morning. Why involve R&D? Because at the naming stage you can already think about how to express the product’s core technology visually. Why involve so many departments? Because that kind of collective idea session is what forces us to think from the user’s point of view.

Q. Conversely, was there a product that didn’t sell as well as you hoped? What did you learn?

Yes. The cocoon filament dryer. We put serious effort into the industrial design, and on the feature side it was all-in-one — drying, weight measurement, API and more. We even fitted a Type-C port as standard for users to DIY with. We went as far as developing a digital-twin website for cocoon so you could experience the product in 3D. And after launch, the only thing users praised was how it looked. We had missed the user’s most essential need and, self-satisfied and top-down, piled on features we assumed were advanced. That lesson landed hard. Since then we’ve put much more weight on how to apply Phaetus technology, how to genuinely read user needs, and how to deliver products that feel good to use.

Arkfly (Fly)

Q. What’s Arkfly’s official position? What decides whether a product carries the Phaetus name or the Arkfly name?

Arkfly is the brand for technology and products relating to the “build platform module” of 3D printing. Extrusion system technology and products fall under Phaetus. The dividing principle is that different core modules of FDM 3D printing are assigned to different brands so each can be developed deeply, and together they deliver a total solution.

Q. Why did a hotend company move into build plates? Where did Conweb’s micro-porous polymer membrane and room-temperature adhesion technology come from?

The core modules of FDM 3D printing include the extrusion system, the motion control system, the build platform system and the smart system — and every one of them is worth rebuilding from scratch. Phaetus is not a company that simply makes hotends. Because our consumer-facing products are hotends and nozzles, the world tends to see us as a hotend and nozzle parts brand; in reality Phaetus is a solutions provider for the entire extrusion system. We supply complete extrusion system solutions, machine by machine, to many major printer manufacturers. That includes flow path technology, feed and extrusion technology, structural design, and technology for adapting to the printing characteristics of each material (wear resistance, non-stick and so on). Arkfly follows the same thinking: a system-level solution for the build platform module. The 1.0 technology roadmap is “beyond the heated bed” — using coating technology to achieve adhesion that holds firmly while hot and releases naturally once cool. We’ve already launched a PLA-specific energy-saving plate that prints at room temperature with no heating at all.

Q. What product areas will Arkfly move into next? Beyond plates — dryers, consumables, peripherals in general?

At this stage, the Arkfly product line will stay focused on build platform solutions.

▼ That said, a rather cool purple Conch does exist!

Market and competition (Fly)

Q. How do you see the current state of Western aftermarket players like E3D, Bondtech, Slice and Micro Swiss? Where does Phaetus win?

This is a personal view, but every aftermarket brand is facing the same reality: the rise of highly integrated complete machines. The DIY-era upgrade parts market took a shock on the scale of an industry restructuring. Phaetus has never taken the “replace the original part” route, right from founding. The reason we designed our brands by module is to dig deep into the extrusion system as a field — offering ODM and OBM capability to printer manufacturers, and high-performance, genuinely valuable upgrade products to end users. Technology-driven, and user experience. That’s the core of our brand.

Q. What’s difficult and what’s fun about building products for closed ecosystems, like parts for Bambu machines (Conch nozzles, Conweb plates and so on)?

The difficulty is that compatibility is always an unknown. If the host machine’s manufacturer changes the structure in a version update, we have no way of knowing when our product will stop being compatible. On that front we’ve recently started working in the form of collaboration and joint research with the manufacturers, so the pace after a product release is coordinated. The fun is being able to create upgrade value for users. In our durability testing we have a record of printing a cumulative 70 kg of carbon and glass fibre composite filament, and compared with the corresponding original configuration, under our test conditions there are cases of flow improving by more than 60%. All from simply bolting it on.

Q. How do you work with reviewers and KOLs around the world? Are there cases where the community’s voice actually changed a product?

Since the DIY era Phaetus has consistently supplied creators with all kinds of products — water-cooled and 2-in-1-out hotends, tungsten carbide and ruby nozzles, and so on. We keep very good working relationships with KOLs and KOCs worldwide, and many of them take part in the Phaetus developer program, joining deep testing and co-creation of new products and technologies. Yuto is exactly that kind of deeply connected partner: he takes part in discussion and testing of new technologies and products, and helps the brand through online promotion and offline market events. And I have to say it — JRRF, which Yuto organises, was a huge success. The venue was packed, and brands got significant exposure. Out of this kind of deep collaboration we’ve incubated several standout products with creators. The “DXC series” extruder, a three-way collaboration with developer D3vil and Creality, has become a hit in the extruder category.

Anyone can apply to the Phaetus Beta Tester (developer) program. Apply here: Phaetus Beta Tester application form. In the Self Introduction field, please do mention that you saw Yuto’s article!

The Japanese market (Wu Jin and Fly)

Q. What’s your impression of the Japanese market and Japanese users? Are enquiries from industrial applications (jigs, prototyping) increasing?

Wu Jin: Japan is a market we’ve consistently taken very seriously. Japanese users demand a great deal in terms of product quality, stability and detail, and that has continuously pushed up our technical and manufacturing standards. From where we sit, interest in industrial applications is clearly still rising — particularly for jigs and fixtures, functional validation and small-lot production. We believe the biggest room for growth in 3D printing from here is not only the consumer market but continued penetration into industry.

Fly: Japan has long had a high proportion of professional users, and very high expectations around product detail. In recent years, with the development of consumer machines, we can feel more and more general users taking an interest in high-performance upgrade solutions. That’s a very positive shift.

Q. In Japan, PRINSFIL carries Phaetus products and AppleTree carries FusRock. How will you strengthen your Japanese presence and support going forward?

Wu Jin: Currently PRINSFIL handles promotion and sales of Phaetus products in Japan, and AppleTree drives the FusRock materials business. As a next step, building on the existing partnerships, we’ll further strengthen localised product training, technical support, after-sales service and marketing. Japanese users care deeply about quality, detail and long-term service. That’s exactly why we won’t stop at selling products. Together with our partners we want to build a complete support structure spanning product experience, application validation and technical service, and focus on developing industrial users and specialist applications. Our goal is for customers in Japan not just to be able to buy the product easily, but to keep using it, stably, and get the most out of it.

Fly: Our Japanese distributors tell us the design-led low-temperature plate and the silicon carbide (SiC) Conch hotend are getting a lot of attention in Japan. Going forward we plan to appear in front of Japanese users together with more printer manufacturers, through joint exhibitions and brand collaborations.

Editor’s note: The Conch series includes a model built for “kaika,” the high-precision nozzle made by TECDIA in Japan. That collaboration actually started because I introduced kaika to Runice. The nozzle is made by TECDIA and the hotend side is built by Runice for the Phaetus brand — a Japan-China collaboration that has finally taken shape.

The kaika-compatible hotend is currently sold through the Phaetus official store only. The nozzles themselves are available from TECDIA’s official kaika shop (BASE) or on Amazon. Compatible printers are the A1, A1 mini, H2D, H2S, H2C (left), P2S and X2D, and the nozzles come in 0.1, 0.2, 0.4 and 1.0 mm.

Q. What do you hope for from Japanese community events like JRRF? And finally, a message for readers in Japan.

Wu Jin: We value community events like JRRF enormously. 3D printing can’t develop without the joint participation of engineers, makers and users. A community is both a place where new technology gets validated faster, and a place where a company can hear the most authentic user voices. Through JRRF I want to have more direct exchange with users in Japan and take real needs back into product development. The Japanese user’s attitude — pursuing quality, detail and long-term reliability — resonates strongly with the philosophy of Runice and Phaetus. Thank you for all the interest and support so far. We’ll keep delivering products that are high-performance, dependable and genuinely solve problems, and move 3D printing technology forward together with partners, engineers and makers in Japan.

Fly: Under Yuto’s organisation, JRRF has created a really good atmosphere for the 3D printing industry. I’m genuinely sorry I couldn’t attend the first one in person. At the next JRRF, we’ll bring our most sincere new technology, new products and new work, and we will absolutely come to meet the players in Japan.

---

For both JRRF2025 and JRRF2026 the exhibiting was done by PRINSFIL, so a Phaetus x PRINSFIL booth next year would be wonderful. I didn’t manage to take photos at JRRF myself, so here are some from TCT, where I did interpreting and translation support.

The next ten years

Q. What will change most in the next ten years of 3D printing?

Wu Jin: I think the biggest change over the next decade won’t be print speed getting faster still — it will be 3D printing genuinely becoming part of smart manufacturing. AI, multi-material, multi-head, robotics and automation will converge step by step, and 3D printing will grow from a single device into a complete manufacturing system. Competition in the industry will shift too, from competition between individual products to competition in core technology and system capability. Whoever can truly fuse materials, hardware, software and AI will have the chance to lead the next generation of 3D printing.

---

At the end of the interview, Fly promised that at the next JRRF they would come with new technology and new products to meet everyone. I hope you’ll be able to check the sequel to this article on the floor at the next JRRF. As for when JRRF2027 will be… still undecided! Shifting dates for TCT ASIA and Formnext Frankfurt make it a headache. On venue size I’d like to secure at least 2,000 square metres for now — so if there’s a company able to help with a venue, please get in touch!

For JRRF matters, please contact info@japanreprapfestival.com.

Runice’s Suzhou plant has moved even since I first got to know them, and the speed at which they relocate that much equipment in that little time is hard to imagine in Japan. The machines on the floor were different from the factories I usually visit — a lot of machines for working long bar stock, which was new to me.

If you’re a hardcore 3D printing user who wants to build your own custom hotend or nozzle and sell it as a brand, or co-develop something, do get in touch with them. They also keep a close eye on social media, so if you use Phaetus products it might be worth posting with a tag!

Links

• Runice official site
• Phaetus official site
• FusRock official site
• Phaetus on X (@phaetus3D)
• Phaetus GitHub — 3D STEP models for their products are generally published, which is genuinely great if you like to mod
• PRINSFIL Amazon store
• AppleTree FusRock brand page

Quoting or republishing this interview is welcome — just credit psych0h3ad.tech and link back to this article. If you do, I’d love to hear about it: reach me on X (@YuTR0N) or via the contact form.

---

[Correction] 13 August 2026: This article previously stated that the kaika-compatible hotend was available on AliExpress. That listing was made in error; it is currently sold through the Phaetus official store only. The relevant passage has been corrected.