Flsun T1 3D printer review

Unlike most 3D printers available today, the FLSUN T1 arrived in a relatively flat box, which was in stark contrast to the tall machine in the images. However, after about an hour of building, sipping coffee and double-checking, the machine was ready to go. Nothing too tricky on the construction side, though I needed to double-check the screws after the first few runs to fix some print quality issues.

Once the machine was complete and I stepped back, the T1 was instantly impressive and stood out from the other desktop 3D printers in the workshop. While Cartesian bed-slingers and increasingly CoreXY machines dominate the market, the T1 uses a Delta mechanism, with its print head suspended between three rapidly moving arms above a circular build platform. Prusa Research is one of the few other mainstream companies to still produce a printer of this style, but that model is aimed at the pro market with a price tag to match.

These delta machines are unusual-looking, but they offer a major speed advantage. Flsun quotes a maximum print speed of 1,000mm/s and an acceleration of 30,000mm/s², which, on paper, at least puts the T1 among the fastest machines I’ve tested.

However, what surprised me most wasn’t the speed. After careful assembly and adjustment, the T1 produced some of the most dimensionally accurate prints I’ve seen from a machine at this price level.

There are compromises, most notably noise, single-filament printing and a more involved setup process. For some, this is unlikely to be the best 3D printer – unless speed is the aim of the game. For rapid prototyping and functional printing, there’s plenty here to like.

FLSUN T1 3D Printer: Design

Unusually for a modern 3D printer, the Flsun T1 arrives essentially flat-packed, so my first job before starting the test was to assemble it, and having seen these machines in action and reviewed a couple of TriLab (now Prusa) deltas in the past, I didn’t fancy my chances.

I’ve built plenty of printers over the years, although mostly Cartesian and, more recently, CoreXY models. While I initially thought the complexity of the Delta would make construction difficult, in reality it was straightforward.

Actually assembling this Delta machine was deceptively straightforward because most of the complicated mechanical elements arrive pre-assembled. It’s largely a matter of fitting panels, securing components and installing the top.

However, my first prints didn’t quite meet my expectations; they weren’t bad, but they weren’t good either. They all had minor surface imperfections, even though the machine appeared correctly assembled.

If I hadn’t tested the Flsun S1 a while ago, I might have dismissed the imperfections; after all, this isn’t an overly expensive machine given the build area. After checking the mechanism again and tightening a grub screw around the suspended head, print quality immediately improved.

The design itself is striking, with the print head hanging between three articulated arms, giving the machine a futuristic appearance. While Flsun makes a wide range of Delta machines, the T1 offers an enclosed heated chamber and even a filament spool holder, which, while not sophisticated, it sits inside the machine, helping keep the filament moisture-free. Essentially, the reel is suspended from a metal rod above the print head. It looks crude, but it worked perfectly throughout testing.

At 436 x 490mm, the footprint is reasonable considering the build volume, although its substantial 836mm height means you’ll need plenty of vertical space.

FLSUN T1 3D Printer: Features

The Flsun T1’s headline feature is its Delta mechanism. While traditional Cartesian printers move components independently along X, Y and Z axes, and CoreXY printers use a belt-driven arrangement to move the print head rapidly across a fixed plane, a Delta printer uses three vertical towers and articulated arms to control the position of its suspended print head. Visually, while a Cartesian and a CoreXY can look very similar, the Delta’s inverted tripod design instantly highlights that it’s something different.

While all 3D printers are fascinating to watch, the Delta system is even more so, and even as you see the print build, you can’t help but think that this system and the design in its complexity are impossible, yet it works. Even after years of using 3D printers, there’s still something slightly alien about seeing three arms rapidly coordinating their movement to position a nozzle accurately above the build plate.

The major advantage of this design is speed, although how or why it works so well is beyond me. Flsun quotes a maximum print speed of 1,000mm/s, with acceleration reaching 30,000mm/s², even with the latest CORE XY machines, those figures are difficult to match.

However, as I’ve seen in the past, fast movement is only useful if the extrusion system can keep pace, and as I found out with the larger S1, FLSUN has once again equipped the T1 with a powerful, if noisy cooling system, cooling system; I’ve also noted that they now sell a silencer kit. The tool head’s dual-gear direct-drive extruder offers a quoted extrusion force of up to 78N, while the 300°C hotend has a maximum volumetric flow rate of 90mm³/s.

Throughout testing, filament delivery was remarkably reliable for a machine of this speed, with plenty of flexibility in the software settings. The spool’s position directly above the tool head meant that the filament follows a relatively straightforward path into the extruder, with fewer bends than on many conventional machines. During the test, I didn’t experience many filament-feed issues, and I ended up having quite a bit of faith in the system feeding older, and increasingly brittle PLA that would have jammed up other printers.

Cooling is a major part of this machine’s success, and it’s especially important when you’re depositing material at this sort of speed. The T1 uses a CPAP high-pressure turbo fan rated at 30,000rpm. It’s effective, but it’s also extremely loud; when it starts running at speed, you’ll know about it.

In fact, one of the first useful prints suggested for the machine is a silencer that fits over the exhaust. It’s worth printing because it noticeably reduces the noise, although the T1 still isn’t a printer I’d particularly want operating beside my desk all day; as mentioned earlier, a silencer kit is now available.

Once constructed, the machine is fully enclosed, which helps both safety and material compatibility. Flsun specifies a chamber temperature of up to 50°C, while the bed can reach 110°C. Combined with the 300°C hotend, that gives the T1 enough thermal capability for materials beyond basic PLA, although out of the box it comes with only a brass nozzle.

The supplied 0.4mm nozzle is brass, so abrasive materials aren’t advisable with the standard hardware. At the time of testing, the Flsun website didn’t list an obvious official hardened-nozzle upgrade, although the E3D-style nozzle arrangement may open the door to third-party alternatives; obviously, check compatibility before fitting one.

During testing, I successfully printed PLA, PETG, ABS, and ASA with consistently good results.

As you’d expect, the machine offers automatic bed levelling, vibration compensation, and input shaping, along with filament detection and power-loss recovery.

A 1080p camera enables remote monitoring and time-lapse capture. It doesn’t provide the sophisticated AI print-failure detection increasingly found on the latest premium machines, but during testing it connected reliably and provided a clear remote view of the print.

The 4.3-inch colour touchscreen is simple but excellent, with an interface that follows the same general approach as the company’s larger machines.

Perhaps the most impressive specification, however, is the build volume. The circular platform offers Ø260mm of horizontal space combined with an impressive 330mm Z height. That’s a substantial printable area for a machine with such a modest footprint.

FLSUN T1 3D Printer: Performance

Getting started took some thought and about an hour to fully unbox and assemble. It’s been a while since I last put this much effort into building a machine, but for the most part the instructions were well documented and shouldn’t be beyond most people. The one point is that you do need to build, double-check, print and then re-check.

The point is that this machine is all about speed, so any small movement in the joints, frame, or anywhere else will be amplified in the print. The more time you put into the construction and pre-flight checks, the better this machine will be. When I first finished construction and ran a test print, the results were good but not quite what I expected.

Minor surface imperfections suggested something wasn’t quite right, and another inspection revealed a grub screw around the Delta mechanism that needed tightening; once that was done, the machine’s speed and print quality suddenly took a leap forward.

Speed was the first feature I tested, and as the first 3D Benchy rapidly appeared on the print bed, it was obvious why these Delta machines still exist. If you need to print stuff quickly, then a Delta’s what you need.

Speed isn’t all; the Flsun T1 also impressed with print quality and dimensional accuracy, and as you notch down that speed, the accuracy of the prints, which was already good, improved further.

FLSUN T1 3D Printer: Print quality

Dimensional accuracy – score of 4

Target 25: X: 24.87mm / 0.13mm Error | Y: 25.00mm / 0.00mm Error
Target 20: X: 19.89mm / 0.11mm Error | Y: 19.97mm / 0.03mm Error
Target 15: X: 14.86mm / 0.14mm Error | Y: 14.92mm / 0.08mm Error
Target 10: X: 9.87mm / 0.13mm Error | Y: 9.86mm / 0.14mm Error
Target 5: X: 4.75mm / 0.25mm Error | Y: 4.72mm / 0.28mm Error

X Error Average = 0.16mm
Y Error Average = 0.106mm
X&Y Error Average = 0.133mm

Fine Flow Control – score of 5
Fine Negative Features – score of 5
Overhangs – score of 5
Bridging – score of 5
XY resonance – score of 2.5
Z-axis alignment – score of 2.5

Adding up the totals gives a final score of 29 out of 30.

Those numbers were reflected in real-world use. Circular features in the dimensional test appeared remarkably clean with little visually apparent ovaling, while separately printed components fitted together snugly.

More importantly, models designed in CAD generally translated directly into usable physical parts without repeatedly adjusting dimensions to compensate for printer inaccuracies.

That makes the T1 particularly useful for prototyping and functional printing. It’s not simply fast; it can produce accurate parts quickly, which is a far more meaningful advantage.

FLSUN T1 3D Printer: Final verdict

The Flsun T1 shows exactly why Delta 3D printers still have a place alongside increasingly sophisticated CoreXY machines. It’s extraordinarily fast, visually distinctive and, once properly assembled, capable of exceptional print quality.

That 29 out of30 benchmark result is impressive and more importantly, the accuracy carried over into practical projects, where components fitted together correctly and CAD dimensions translated well to printed parts.

There are compromises. The CPAP cooling system makes the T1 extremely loud, even with the recommended silencer. Assembly also requires greater care than today’s almost appliance-like CoreXY machines. Tightening every bolt and grub screw properly can significantly improve print quality.

It’s also strictly a single-filament printer, with no straightforward equivalent to the increasingly common automatic multifilament systems.

However, those limitations matter less if your priority is functional printing, such as for product designers, engineers, makers and workshops producing prototypes or mechanical components; the combination of speed, accuracy and substantial build volume is will be more important.

The T1 isn’t the most polished 3D-printing experience, but once correctly configured, it’s an exceptionally good machine.

The Flsun T1 makes the most sense if speed and dimensional accuracy matter more than multicolor printing or complete plug-and-play simplicity. Its Delta mechanism delivers extremely fast movement, and my testing showed that speed doesn’t have to come at the expense of accuracy.

Product designers, engineers, makers, and small workshops producing prototypes should find plenty to appreciate, particularly given the build volume. Beginners who want the simplest possible experience may prefer a modern, pre-assembled CoreXY printer. Likewise, anyone mainly interested in multicolour decorative models should look for machines with automatic multifilament systems instead.

Should I buy the Flsun T1 3D printer?