Hacking The System In A Moral Panic: We Need To Talk

March 17, 2026 by Jenny List No comments

It seems that for as long as there have been readily available 3D printers, there have been moral panics about their being used to print firearms. The latest surrounds a Washington State Legislature bill, HB2320, which criminalises the printing of unregistered guns. Perhaps most controversially, it seeks so impose a requirement on printers sold in the state to phone home and check a database of known firearms and refuse to print them when asked.

This has drawn a wave of protest from the 3D printing community, and seems from where we are sitting to be a spectacularly ill-conceived piece of legislation. It’s simply not clear how it could be implemented, given the way 3D printers and slicing software actually work.

Oddly This Isn’t About Firearms

The root of the problem with this bill and others like it lies in ignorance, and a misplaced belief in the power of legislation. Firearms are just the example here, but we can think of others and we’re sure you can too. Legislators aren’t stupid, but by and large they don’t come from technology or engineering backgrounds.

Meanwhile they have voters to keep happy, and therefore when a moral panic like this one arises their priority is to be seen to be doing something about it. They dream up a technically infeasible solution, push to get it written into law, and their job is done. Let the engineers figure out how to make it work. Continue reading “Hacking The System In A Moral Panic: We Need To Talk” →

Two test towers, showing the palette potential of three (R, B, Y) filaments.

FullSpectrum Is Like HueForge For 3D Models, But Bring Your Toolchanger

March 17, 2026 by Tyler August 4 Comments

Full-color 3D printing is something of a holy grail, if nothing else just because of how much it impresses the normies. We’ve seen a lot of multi-material units the past few years, and with Snapmaker’s U1 and the Prusa XL it looks like tool changers are coming back into vogue. Just in time, [Radoux] has a fork of OrcaSlicer called FullSpectrum that brings HueForge-like color mixing to tool changing printers.

The hook behind FullSpectrum is very simple: stacking thin layers of colors, preferably with semi-translucent filament, allows for a surprising degree of mixing. The towers in the image above have only three colors: red, blue, and yellow. It’s not literally full-spectrum, but you can generate surprisingly large palettes this way. You aren’t limited to single-layer mixes, either: A-A-B repeats and even arbitrary patterns of four colors are possible, assuming you have a four-head tool changing printer like the Snapmaker U1 this is being developed for.

FullSpectrum is in fact a fork of Snapmaker’s fork of OrcaSlicer, which is itself forked from Bambu Slicer, which forked off of PrusaSlicer, which originated as a fork of Slic3r. Some complain about the open-source chaos of endless forking, but you can see in that chain how much innovation it gets us — including this technique of color mixing by alternating layers.

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Recycled Plastic Compression Molding With 3D-Printed Molds

March 16, 2026 by Maya Posch 6 Comments

Recycling plastic at home using 3D printed molds is relatively accessible these days, but if you do not wish to invest a lot of money into specialized equipment, what’s the most minimal setup that you can get away with? In a recent [future things] video DIY plastic recycling is explored using only equipment that the average home is likely to have around.

Lest anyone complain, you should always wear PPE such as gloves and a suitable respirator whenever you’re dealing with hot plastic in this manner, just to avoid a trip to the emergency room. Once that issue is taken care of, there are a few ways of doing molding, with compression molding being one of the most straightforward types.

With compression molding you take two halves of a mold, and one half compresses the material inside the other half. This means that you do not require any complex devices like with injection molding: just a toaster oven or equivalent to melt the plastic, which is LDPE in this example. The scrap plastic is placed in a silicone cup before it’s heated so that it doesn’t stick to the container.

The wad of goopy plastic is then put inside the bottom part of the mold before the top part is put in place and squeezed by hand until molten plastic comes out of the overflow opening(s). After letting it fully cool down, the mold is opened and the part released. Although the demonstrated process can be improved upon, it seems to work well enough if you are aware of the limitations. In terms of costs and parts required it’s definitely hard to come up with a cheaper way to do plastic molding.

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How I 3D Printed My Own Lego-Compatible Train Bridges

March 16, 2026 by Lewin Day 23 Comments

Lego train sets have been available for decades, now. The Danish manufacturer long ago realized the magic of combining its building block sets with motors and plastic rails to create real working railways for children and adults to enjoy. Over the years, Lego has innovated through several generations of trains, from classic metal-rail systems to the more modern IR and later Bluetooth-controlled versions. The only thing largely missing over all that time, though…? A bridge!

Yes, Lego has largely neglected to build any bridges for its mainstream train lineup. There are aftermarket solutions, and innovative hacks invented by the community, all with their own limitations and drawbacks. This glaring oversight, though, seemed like a perfect opportunity to me. It was time to fire up the 3D printer and churn out a fully-realized Lego rail bridge of my very own.

Bridges Are Hard

I’ve experimented with building Lego rail bridges before, using standard track and household objects like cardboard, books, and beer. Unfortunately, it can be very difficult to support the track evenly at the joints which occur every 150mm, and derailments are common. Credit: author

There’s actually a good reason Lego bridges aren’t a big thing in the company’s own product lineup, beyond a few obscure historical parts. This is probably because they aren’t very practical. Lego locomotives are not particularly strong haulers, nor do they have excellent grip on the rails, and this makes them very poor at climbing even mild grades. Any official Lego bridge would have to be very long with a shallow slope just to allow a train to climb high enough to clear a locomotive on a track below. This would end up being an expensive set that would probably prove unpopular with the casual Lego train builder, even if the diehard enthusiasts loved it.

There are third-party options available out there. However, most rely on standard Lego track pieces and merely combine them with supports that hold them up at height. This can work in some cases, but it can be very difficult to do cool things like passing a Lego train under a bridge, for example. It can be hard to gain enough height, and the short length of Lego track pieces makes it hard to squeeze a locomotive between supports. Continue reading “How I 3D Printed My Own Lego-Compatible Train Bridges” →

A Smart Printer Enclosure For The Open Source World

March 15, 2026 by Ian Bos 15 Comments

3D printing has had its time to spread its wings into the everyday home, yet many of those homes lack the proper ventilation to prevent the toxic VOCs from escaping. Because of this, [Clura] has put together an entire open-sourced smart enclosure for most open concept printers.

While certain 3D printers or filament choices lend themselves to being worse than others, any type of plastic particles floating around shouldn’t find their way into your lungs. The [Clura] enclosure design includes HEPA and carbon filters in an attempt to remove this material from the air. Of course, there’s always the choice to have a tent around your printer, but this won’t actually remove any VOCs and air located inside a simple enclosure will inevitably escape.

What makes this enclosure different from other, either commercial or open-source designs, is the documentation included with the project. There are kits available for purchase, which you may want for the custom PCB boards for smart features such as filament weighing or fume detection. Even still, if you don’t want to purchase these custom boards the Gerber files are available on their GitHub page.

As smart as this enclosure is, it still won’t fix the issues of what happens to the toxins in your print after it’s done printing. If you are interested in this big picture question, you are not alone. Make sure to stay educated and help others learn by checking out this article here about plastic in our oceans.

Selective Ironing Adds Designs To 3D Prints

March 12, 2026 by Donald Papp 9 Comments

While working on a project that involved super-thin prints, [Julius Curt] came up with selective ironing, a way to put designs on the top surface of a print without adding any height.

For those unfamiliar, ironing is a technique in filament-based 3D printing that uses the extruder to smooth out top surfaces after printing them. The hot nozzle makes additional passes across a top surface, extruding a tiny amount in the process, which smooths out imperfections and leaves a much cleaner surface. Selective ironing is nearly the same process, but applied only in a certain pattern instead of across an entire surface.

Selective Ironing can create patterns by defining the design in CAD, and using a post-processing script.

While conceptually simple, actually making it work was harder than expected. [Julius] settled on using a mixture of computer-aided design (CAD) work to define the pattern, combined with a post-processing script. More specifically, one models the desired pattern into the object in CAD as a one-layer-tall feature. The script then removes that layer from the model while applying the modified ironing pattern in its place. In this way, one can define the pattern in CAD without actually adding any height to the printed object. You can see it in action in the video, embedded below.

We’ve seen some interesting experiments in ironing 3D prints, including non-planar ironing and doing away with the ironing setting altogether by carefully tuning slicer settings so it is not needed. Selective Ironing is another creative angle, and we can imagine it being used to embed a logo or part number as easily as a pattern.

Selective Ironing is still experimental, but if you find yourself intrigued and would like to give it a try head over to the GitHub repository where you’ll find the script as well as examples to try out.

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Hands On With Creality’s New M1 Filament Maker

March 11, 2026 by Tyler August 28 Comments

Ever since 3D printing has become a popular tool, the question of waste has been looming in the background. The sad reality of rapid prototyping is that you’re going to generate a lot of prints that just aren’t fit for purpose, even if your printer runs them off perfectly every time. Creality has some products on the way aimed at solving that problem, and [Embrace Making] on YouTube has got his hands on a pre-production prototype of the Creality M1 Filament Maker to give the community a first look.

The M1 is actually only half of the system; Creality is also working on an R1 shredder to reduce your prints into re-usable shreds. [Embrace Making] hasn’t gotten his hands on that, but shredding prints isn’t the hard part. We’ve featured plenty of DIY shredders in the past. Extruding filament reliably at home has traditionally proven much more difficult, which is why we mostly outsource it to professionals.

Lacking the matching shredder, and wanting to give the M1 the fairest possible shake, [Embrace] tests the machine out first using Creality-supplied PLA pellets. The filament diameter isn’t as stable as we’ve gotten used to, and the spool rolling setup needs a bit more work.

Again, this is an early prototype. Creality says they’re working on it and claims they’ll get to ±0.05 mm precision in the production models. Doubtless they’ll also fix the errors that led to [Embrace]’s messy spool. That’s probably just software given that the winding mechanism did a pretty good job on the Creality-supplied spool.

Most importantly, the M1-produced filament does print. The prints aren’t perfect due to the variation in diameter, but they turn out surprisingly well for home-made filament. [Embrace] also shows off the ability to mix custom colors and gradients, but, again, using raw PLA rather than shredded material. Hopefully Creality lets him test drive the R1 shredder once its design is further along.

This is hardly the first time we’ve seen a filament extruder. The goal of this product is to pair with a shredder and use it for recycling, but if you’re going to stick with raw plastic pellets, you may as well print them directly.

Continue reading “Hands On With Creality’s New M1 Filament Maker” →