FLSUN S1 Pro 3D Printer + 3 Free Filaments – Limited Time(July 21-31)

in alcuni punti la stampa è leggermente disuniforme e presenta piccoli difetti, ma più che accettabili visto la velocità incredibile a cui lavora ! Molto ricca la cassetta degli attrezzi, sarebbe apprezzabile un cassetto nella scocca per poterla contenere, come nella FLSUN Super Racer.

In some places the print is slightly uneven and has small defects, but more than acceptable given the incredible speed at which it works! The toolbox is very well stocked, a drawer in the chassis to store it would be appreciated, like in the FLSUN Super Racer.

I have had the S1 Pro for a week now, and it has been running perfectly. After ordering the printer, I read several harsh reviews that made me reconsider my choice. While I have only had the printer for a little over a week, I believe some reviews are just from YouTubers looking to create content. I think FLSun should seriously reconsider the "creators" they sponsor with a printer. Most of them make silly unboxing videos that lack technical depth and then move on to begging for another printer to review. FLSun, please sponsor more people who actually contribute by creating optimal filament profiles for your printers and sharing those profiles; that would help your customers. Consider sponsoring creators who produce 3-5 educational videos and those who develop upgrades for printers. This approach would help grow your community.

Okay here is my short review after a week:

🖨️ First Impressions & Performance
• Uptime & Print Speed
• Out of the box, the S1 Pro was impressively fast. My typical 10-hour print now completes in about 5 hours; shorter 2-hour prints can be done in ~45 minutes (depending on filament and quality settings).
• Startup is efficient—even with full calibration routines, it’s faster than comparable models like the P1S. Over the past week, it’s been reliable without any major issues.
• Size & Footprint
• The machine is significantly larger than anticipated—too big for my intended setup space. Despite this, the performance tradeoff has made it worthwhile.
• Minor Issues Encountered
• Only one clog so far, and it was due to the filament getting caught in the detector—not a flaws with the hotend or core mechanics.

🛠️ Reliability & Technical Support
• Customer Service
• FLSUN support has been responsive, replying within 24–36 hours to my inquiries.
• Firmware & Open Source Philosophy
• FLSUN appears committed to an open-source direction, which is great. However, this isn’t highlighted enough in their marketing.
• The community around the S1 is still quite small. I’d love to see FLSUN sponsor more actual technical creators or developers to grow it further.
• There is a lack of profiles, it would be great if FLSun sponsored Viking3DK who provided good profiles for T1 and Sponsor Guislain Cyril (Guilouz) creator of FLSun S1 open source edition, collaborate to make your products better!!.

⚙️ Hardware, Upgradability & Community Ecosystem
• Modular Design & Compatibility
• The S1 shares many parts with the T1 series—such as belt tension systems—which suggests potential for standardized upgrades across models.
• Access to the hotend in the extruder could be easier. Collaboration with third-party manufacturers (ED3, etc.) to develop compatible upgrades would be a big win—especially helpful if FLSUN faces supply chain delays.
• Documentation & Learning Resources
• FLSUN’s wiki is a good start, but still lacks depth in several areas. They’ve begun adding helpful video tutorials, which is encouraging. More detail and hands-on guides would make it even stronger.

💻 Software & Firmware
• Slicer Options
• FLSUN bundles a branded version of OrcaSlicer, their version 2.0 is fine and currently up to date. But having access to vanilla OrcaSlicer is even better—it’s updated more frequently and receives new features quicker.
• Firmware Roadmap & AI Features
• It seems FLSUN is currently prioritizing the T1 model, which might delay improvements to S1 Pro firmware. I hope they engage with open-source firmware contributors to accelerate ongoing AI enhancements, which currently don’t work as well as expected.

🔧 Modifications & Accessories
Here’s what I’ve upgraded or am planning to:
1. Bowden tube & quick-release connectors – for easier filament changes
2. BondTech CHT BiMetal 0.4 mm nozzle – aiming for higher flow rates
3. Silencer with baffle – the printer is quite loud, so I printed the “CPAP Turbo Fan Silencer V2” - currently the best one (Printables)
4. Desiccant Box's for FLSun S1 (also found on Printables) and order a 1 kg of silica desiccant.

✅ Final Take

The FLSUN S1 Pro delivers fast, high-quality prints and for the short time i have had the printer reliable operation—and with the proper setup, it can produce significantly better quality prints at high speeds than many other brands. 14 hour larger prints was printed in ~6h with adjusted Ironing settings the top surface was super smooth. While the machine is large and its ecosystem is still growing, FLSUN’s open-source direction makes me very happy, there is a third-party upgrade potential, and if FLSun puts some effort into it a hopefully active firmware community makes it a promising long-term investment. I give it 4 out 5 as want to see FLSun put more effort in growing the ecosystem, not just making the next new model. And I hope it keeps on running :-)

This is my first Flsun and also my first Delta-style 3D printer. It’s truly something else — easily twice as fast as my Bambu X1, and that’s even with the speed turned down a bit to match print quality. The result? Same quality as the Bambu, but always in half the time or less.

I honestly don’t get all the talk about the noise. After reading the reviews, I expected a lot worse. Sure, it’s not silent — but you’re pushing a lot of air to print fast, so you can’t have your cake and eat it too. That said, the sound doesn’t bother me at all. I have bedslingers that are far noisier.

At the current price of $999, it’s an absolute steal. The only thing I wish is that Flsun would move toward full open source.

Initially some problem with thw motors , and the slicer but overall a good printer , a strange form factor but the print quality is good enough and the printer is very fast !

ricevuta stampante e tutto regolare; abbiamo eseguito le prime stampe e sono molto buone; siamo contentissimi della stampante.
Cordialità IN&OUT Robotics S.r.l. Italia