A clear tank of gel is shown against a black background. In the gel, the shape of a white plastic boat is suspended. A coarse-tipped needle dips into the top of the gel bath.

Support Bath Enables An Epoxy Benchy

August 27, 2026 by Aaron Beckendorf 6 Comments

There’s plenty of substances that can theoretically be extruded from a nozzle, but only a regrettably small subset of them can actually be used for 3D printing. One limiting factor is the liquid range: too high a melting point and it’s hard to reliably extrude, too low and it tends to ooze and flow once extruded. Embedded 3D printing offers a way around this: it submerges the entire print in a shear-thinning support gel which keeps liquids in place until they solidify. [Riley] of Riley’s Lab recently built such a 3D printer and used it to print in silicone and epoxy.

In place of the extruder, [Riley] mounted a mostly 3D printed syringe pump, which allowed him to squirt out almost any liquid. For a test, he printed a tardigrade model out of cream cheese. This was a good test material for several reasons: it’s cheap, easy to extrude, and holds it shape well after extrusion. Silicone and epoxy, however, won’t hold their shape, which is where the support bath comes it. This was a mixture of mineral and vegetable oil, with some fumed silica added to make it thick yet shear-thinning. This lets it contain the extruded liquid, yet flow as the extrusion needle slices through it.

For the first test, [Riley] printed a Benchy out of Sylgard 184. The outcome looked good in the bath, bar some stringing, but it seemed to have limited adhesion between layers, and disintegrated upon removal from the bath. A second test with a two-part epoxy worked much better; it also had some stringing, but it held together while the bath was washed away in isopropyl alcohol, and even seemed decently shock-resistant afterwards.

It’s great to see a hacker working on this technology; we’ve previously covered a commercial take on it, as well as some of the research that led to it.

Continue reading “Support Bath Enables An Epoxy Benchy” →

3D-Printed Skin Gives Robots The Sensation Of Touch

August 24, 2026 by Maya Posch 6 Comments

Schematic diagram of the touch-sensitive skin. (Credit: Haofeng Chen et al., ArXiv, 2026)

Hypoesthesia, more commonly referred to as numbness, is one of the more distressing ailments that can affect us humans, primarily because it reminds us of just how much we rely on our sensation of touch in daily life. From experiencing the world around us, handling objects, noticing when you just bumped into that side table again and the comforting hug of a fellow human being, touch is perhaps the most important of our senses.

In that regard the recently published research by [Haofeng Chen] et al. on giving robots a skin that can experience touch seems rather important as it would give especially humanoid robots a more natural way to interact with their environment, using feedback from touch. Continue reading “3D-Printed Skin Gives Robots The Sensation Of Touch” →

3D Printing A Railway Pump Car

August 23, 2026 by Maya Posch 19 Comments

It's arguably adult-sized. (Credit: Sam Barker, YouTube) — It’s arguably adult-sized. (Credit: Sam Barker, YouTube)

A staple of old movies featuring railways, many handcars – also called pump trolleys or pump cars – feature the characteristic seesawing beam. Requiring at least two people, the motion of this beam is subsequently converted into the rotating motion of the wheels, propelling it at a leisurely pace across the tracks. As a fun and yet functional mechanical contraption it also makes for an entertaining 3D printable project, which is what [Sam Barker] and [Tom] did.

You can find the entire project over at Printables if you are feeling the itch as well, though as of writing details on the required bolts and shafts are still pending.

Since the entire assembly had to be lugged over to the Open Sauce event in the US, they had to design it to be small enough to fit into check-in luggage and easy enough to reassemble in a hotel room. Naturally this put some constraints on the full size of the contraption, with it omitting compatibility with standard gauge railways and also being decidedly fun-sized.

That said, it seems to have left an impression on the folk over at Open Sauce, and it’s hard to argue with the sheer fun factor of such a co-op mode of transportation. Even if bicycle-style handcars are more popular these days, especially for tourist purposes, the old seesaw-style has that certain charm to it.

Continue reading “3D Printing A Railway Pump Car” →

The Shutter Makes This 3D Printed Camera Special

August 22, 2026 by Jenny List 9 Comments

Making a film camera is a project within the reach of almost anyone, from the experimenter with cardboard and sticky tape, to the machinist with an aluminium billet. But 3D printing has opened up the world of cameras to whole new set of experimenters, and we’ve seen some very impressive builds here as a result. For all that, there’s always been a particularly tricky aspect to a home made camera: the shutter. In particular, making one with variable speed has proved almost impossible. Now [Camera Things] has given it a very good shot, with a sliding 3D printed design.

To cock it, both the strips are pulled across, before the blind strip is pushed back, and the shutter operates by sliding back under the influence of a rubber band. The clever part in this case is that the blind strip can be partially pushed back to affect the size of the shutter opening. The effect is then of a variable width strip of light passing over the film, which is equivalent to varying the speed of a conventional shutter.

Due to space constraints he’s only able to make it a half frame shutter, so he’s abandoning this design in favour of a more complicated set of vertical leaves. Sadly he’s not made the files available, but we thing proficient CAD users should be able to make their own version. The video is below the break.

It’s not the first printable shutter we’ve seen, but it remains the first variable one.

Continue reading “The Shutter Makes This 3D Printed Camera Special” →

3D Printering: Why Is My PLA So Brittle?

August 20, 2026 by Maya Posch 29 Comments

Over the years poly(lactic acid) (PLA) – also known as polylactide – has become a popular thermoplastic for a variety of reasons. One of these reasons is that it’s easily produced from a renewable resource, i.e. lactic acid, with the resulting polymer even being compostable if you assume that your compost pile hits a steady 65°C or more, well above the polymer’s glass transition temperature (Tg).

That said, PLA by itself is a pretty crummy material, being exceedingly brittle and inferior to common alternatives like PET(G) in many metrics. Over the decades much research has gone into figuring out this material, its amorphous and crystalline states, as well as how to use plasticizers, copolymers, mechanical manipulation and PLLA/PDLA blends to produce more useful variants of PLA.

Today’s spools of thermoplastic filament that gets marketed as ‘PLA’ are the result of such engineering, though with plenty of remaining issues, as anyone who has struggled through a spool of brittle PLA filament can attest to. Although you can find plenty of tips online about how you should ‘just’ toss said spool into an filament dryer, oven or similar to bake it – with accusing fingers pointed at moisture intrusion, hydrolysis and kin – it helps to understand the fundamentals of how PLA works, and how it degrades.

Continue reading “3D Printering: Why Is My PLA So Brittle?” →

A Hot End And Material Database For 3D Printing

August 18, 2026 by Zoe Skyforest 17 Comments

When it comes to 3D printing in the FDM world, you can go a long way just relying on standard settings that ship with your 3D printer and/or slicer. If you want to push the limits, though, it pays to better understand the hardware and materials you’re working with to know what you can get away with. To that end, [Robert Samples] put together the MeltCalc database to help.

The purpose of MeltCalc is simple—it collates data on hot ends and materials regarding factors like maximum flow rate, print speeds, and heater requirements. If you’re wondering whether a given hot end can flow a given filament at a given rate, for example, this tool is a great place to start. It features 64 different hot ends and 36 polymers typically used in the 3D printing world, and can spit out maximum flow rates and print speed estimations even accounting for fancy tech like Core Heating Technology (CHT) nozzles. It’s all based on thermodynamic modelling which [Robert] put together based on his experience as a chemist who works with polymers. His aim was to provide a tool with realistic flow rates for hot ends, so that end users don’t have to just rely on often-optimistic marketing numbers.

For those eager to dive deeper into the code and modelling, the project source is available on Github. We’ve featured all kinds of other useful hacks in this space lately, too, like our recent look at how to achieve wave overhangs. If you’ve got your own nifty 3D printing tools in the works, don’t hesitate to notify the tipsline.

Printing FDM Filaments That Are Just Plain Weird

August 17, 2026 by Maya Posch 18 Comments

The fun thing about thermopolymers like PLA is that you can blend in additives, some of which are necessary to make it at all usable, while so many other additives are either just cosmetic or arguably just plain weird. In a recent video, [Zack Freedman] goes over some of the weirdest ones that he’s come across so far.

These range from the pretty-normal-but-unusual, like CMYK sets of filament for full-color printing, to the rather unusual, like very silky PETG and foamy TPU and TPE, all the way to the WTAF ones, such as Timeplast filaments that can be used as soap as well as fish food.

He also tried a range of filaments that vie for being the blackest filament possible, while others pretend to be paper or are made out of literal landfill trash. Some hit your olfactory senses with a hammer by smelling like all the lemons just got squirted right up into your nose, purportedly to keep flies at bay. There is also pumpkin spice-flavored PLA, for when you really need to make the holidays extra fragrant.

Overall, the range of filaments here is quite dizzying, with some being actually practical, while others are mostly about their green credentials, or about being pretty or having a specific olfactory experience. Whether any of them are for you depends. Do you have a longing for 3D prints that smell like pumpkin spice or are fish food? We’ve noticed before that [Zack] likes strange filament.

Continue reading “Printing FDM Filaments That Are Just Plain Weird” →