PreFlight Slicer Brings Added Part Strength Feature, And Many More

May 15, 2026 by Donald Papp 31 Comments

Interested in taking some wild new 3D printing features for a test drive? preFlight is a free and open source slicer that brings a host of processing improvements as well as fascinating new features and interesting twists on old ones. There are almost too many to list, so here are a few that caught our eye.

Cross-sectional view of *Interlocking Perimeters*, which increases Z-strength. Unlike brick layers, layer height stays constant.

Want to mix and match different support types on the same object? No problem. How about use Nip & Tuck seams to better hide where layers start and stop? You can emboss images directly onto print surfaces with a real-time preview and use smart bridging for counter-bored holes. We particularly like the ability to preview a sliced object from the side instead of just by layer. That’s not all, either.

Those features alone are pretty intriguing, but there’s one in particular that is particularly relevant to creating stronger parts. Interlocking Perimeters increases layer bonding to increase object strength. Unlike brick layers, which staggers layers vertically, interlocking perimeters plays with spacing and compression to increase bonding in the Z axis while keeping layer heights constant. This is possible thanks in part to the greater control offered by Athena, the new perimeter generator.

There are plenty more features — like a full Python runtime embedded directly into the slicing pipeline, and a host of export pathways — so check out the GitHub repository for added detail and let us know in the comments if you give it a try.

Using A Nintendo Switch To Speed Up A 3D Printer

May 15, 2026 by Zoe Skyforest 6 Comments

3D printers are almost never fast enough. [Cocoanix] had a Prusa MK3S with this very problem. He found it to be disappointingly tedious when completing even simple prints, and sought a way to make it faster. Thus, he grabbed a Nintendo Switch and got to work.

It might sound like an odd choice, and that’s because it is. There’s no special magic inside a Nintendo Switch that makes 3D printers faster – it’s just that the handheld console was a useful platform on which to run Klipper. As [Cocoanix] explains, Klipper is designed to run on faster general-purpose computers compared to the more limited microcontrollers used in some printers. It’s designed to off-load complex motion processing tasks to a faster CPU, while the printer’s onboard microcontrollers are freed up to simply handle the low-level tasks of driving the motors and so on. An older printer equipped with Klipper can often print faster, while implementing techniques like input shaping to further improve speed as well as print quality.

It’s worth noting that you don’t have to use a Nintendo Switch for this. It’s just a good hook for the YouTube video. Typically you’d use a Raspberry Pi or some other computer instead, but the fact it runs on a jailbroken console is amusing nonetheless. It’s also cool to see the results – in this video, [Cocoanix] got the Benchy printing time down from 90 minutes to just 8.

We’ve previously discussed the benefits of Klipper at length.

Continue reading “Using A Nintendo Switch To Speed Up A 3D Printer” →

Multimaterial SLA Printer Will Make Your Head Spin

May 10, 2026 by Tyler August 7 Comments

For the last few years, the must-have feature that companies are competing to show off on their filament deposition 3D printers is multi-material printing. Be it tool swapping or a material-changing system, everyone wants to show they can give you the capability to make multicoloured plastic tchotchkes. So far, that hasn’t really been the case in the world of at-home resin printing — until now. A company called Polysynth, headed by a fellow named [Eric], hopes you’ll pay a premium for the ability to make multimaterial resin prints, and they show some interesting use cases in the video below.

The technique is simple: instead of one resin tank underneath the dipping build plate, [Eric]’s Polysynth printer has a carousel of up to eight small circular tanks. To avoid cross-contamination from uncured resin, the print needs to be cleansed between alternating dips in the different resin vats. Rather than add a wash vat and slow the process down that way, [Eric] and his team decided to use centrifugal force: they just spin the print really, really fast to fling all the uncured resin to the sides of the vat. Yes, really.

Continue reading “Multimaterial SLA Printer Will Make Your Head Spin” →

The Noctua Fan Files And The Limits Of 3D Printing PC Fans

May 9, 2026 by Maya Posch 24 Comments

After Noctua recently released CAD files for a range of their computer fans, one of the first thoughts that popped up for most people was: Can you just to 3D print their fans? Even though Noctua begs you not to 3D print the files and even says they changed the design slightly so it wouldn’t be the same anyway, the question persists. Fortunately, [Steve] of Gamers Nexus is here to help us answer the question of whether it makes sense to 3D print a computer fan.

Unsurprisingly, the answer is mostly a resounding ‘no’. After reworking the original CAD models to be both printable on a Bambu Lab FDM printer and printing the parts in PLA, the arguably most important part, the motor, still had to be sourced from an original Noctua fan. Although you could source a cheaper motor, that could change the fan’s characteristics.

The other issue is materials. The special polymer that Noctua uses for its fans is designed not to change shape significantly when the fan blades are spinning, whereas PLA and basically every other thermoplastic will likely deform enough to hit the inside of the fan with the blades. For this reason, a 3 mm gap was used in the PLA print compared with the approximately 0.5 mm gap of the original Noctua fan.

Using the professional fan tester and semi-anechoic chamber over at Gamers Nexus, the original and replica fans were compared, showing that the 3D-printed fan had a similar noise profile but produced only about half the airflow. This is likely due to the blade shape and angle, the increased gap, and probably a dozen other details that presumably justify putting a cool $40 down for the original fan.

In short, you’re probably best off using these Noctua fan CAD models for fit testing in a larger CAD model, or 3D printing it for a similar purpose, rather than for a functional fan design. At least now we know. Thanks, [Steve].

Continue reading “The Noctua Fan Files And The Limits Of 3D Printing PC Fans” →

How To Avoid Failed Screw Holes In 3D Printed Parts

May 7, 2026 by Donald Papp 21 Comments

Screws are useful fasteners for 3D prints, but the effectiveness of a screw (not to mention the ease or hassle of insertion) depends on the hole itself. This comprehensive guide on how to design screw holes in 3D printed parts takes guesswork out by providing reference tables as well as useful general tips.

The guide provides handy tables saying exactly how big to design a hole depending on screw type, material (PLA, PETG, or high-flow PETG) and whether the hole is printed in a vertical or horizontal orientation. This takes the guesswork out of screw hole design.

There’s no reason to guess the right size of hole for a screw, just refer to some handy tables.

The reason for different numbers is because multiple (but predictable) variables affect a 3D-printed hole’s final dimensions. Shrinkage, filament properties, and printing orientation can all measurably affect small features like screw holes; accounting for these is the difference between a good fit, and cracking or stripping.

In addition to the tables, there are loads of other useful tips. Designing lead-ins makes screws easier to insert and engage, and while increasing walls is an easy way to add strength it’s also possible to use 3D-printed microfeatures which are more resistant to distortion and don’t depend on slicer settings. There’s even suggested torque amounts for different screw and material types.

Sure, the most reliable way to get a hole of a known size is to drill it out yourself. But that’s an extra step, and drill bits aren’t always at hand in the desired sizes. The guide shows that it is entirely possible to print an ideal screw hole by taking a few variables into account.

If your design calls for screws, be sure to check it out and see if there’s anything you can use in your own designs.

3D Printed Train Whistles Sound Out At Full Scale

May 7, 2026 by Tyler August 10 Comments

The age of steam is long gone, but there are few railfans who don’t have a soft spot for the old rolling kettles. So you’d best believe when [AeroKoi] talks about 3D printed train whistles, that’s steam whistles. Generally speaking, Diesels have horns.

You would not expect printed plastic to hold up to live steam– but that’s why [AeroKoi] uses compressed air. Besides, it’s a lot easier to both justify and maintain an air compressor than a boiler in the shop. At least some hobbyists say it doesn’t make a huge difference with brass whistles, so it should be good enough for plastic. What’s interesting is that even with 120 PSI blasting through them, these multi-part prints held together and sounded amazing.

[AeroKoi] does demonstrate there was a learning curve to climb before he had a good whistle design, and shows you what features worked best. He shared two successes on Thingiverse: A 6-Chime whistle from the Sante Fe Railroad, and a Northern Pacific 5-chime whistle, both 4″ in diameter and printed in vertically sectioned parts. The Northern Pacific is not to be confused with the totally different Union Pacific Railroad, whose famous “Big Boy” also had a whistle feature in the video — though evidently he’s not as happy with it, since he did not share the design.

Those are all North American designs, but there’s no reason this technique wouldn’t work to replicate a more European sound; one of his early experiments was kind of going in that direction already. Of course if you want a perfect replica, the old ways are the best ways: cast brass and live steam. We’ve had a few articles about train whistles in the past, one of which was a doorbell.

Continue reading “3D Printed Train Whistles Sound Out At Full Scale” →

Direct FDM Printing With Granules

May 6, 2026 by Maya Posch 16 Comments

The idea of FDM 3D printing using granules rather than filament is an appealing one: rather than having to wrangle spools of filament that need to adhere to strict dimensions and cannot be too flexible, you can instead just keep topping up a big hopper with fresh granules. This is what [HomoFaciens] has been tinkering with for a while now, with their Direct Granules Extruder V7.0 showing significant improvements.

There’s also an accompanying article, with details of previous granule extruder attempts detailed on the same site. Many of the improvements here focus on making sure the granules melt properly before they reach the end of the extruder, with the auger screw helping to push things along. While this seems straightforward, there are many details to get right, with the previous v6.2 version having issues like the hot plastic backing up into the cold section and clogging things up.

For the test bench a Prusa Mk4 FDM printer is used, with the standard extruder swapped for the experimental extruder. On the extruder the cold, top part is water cooled to ensure it stays cold, with each turn of the wood-screw-turned-auger providing the right extrusion speed. As can be seen with the print tests, the results look pretty good despite the extruder not having been tuned yet.

If you want to give it a shot yourself, the article page provides files for download.

Continue reading “Direct FDM Printing With Granules” →