A man’s hands are shown in the foreground holding two splines, each with teeth both on the interior and exterior surfaces. Both are identical in shape, but one is larger and made of plastic, and the other is smaller and made of metal.

Freeze-drying For Improved Metal Printing

June 6, 2025 by Aaron Beckendorf 12 Comments

For all the remarkable improvements we’ve seen in desktop 3D printers, metal printers have tended to stay out of reach for hackers, mostly because they usually rely on precise and expensive laser systems. This makes it all the more refreshing to see [Dan Gelbart]’s demonstration of Rapidia’s cast-to-sinter method, which goes from SLA prints to ceramic or metal models.

The process began by printing the model in resin, scaled up by 19% to account for shrinkage. [Dan] then used the resin print to make a mold out of silicone rubber, after first painting the model to keep chemicals from the resin from inhibiting the silicone’s polymerization. Once the silicone had set, he cut the original model out of the mold and prepared the mold for pouring. He made a slurry out of metal powder and a water-based binder and poured this into the mold, then froze the mold and its contents at -40 ℃. The resulting mixture of metal powder and ice forms a composite much stronger than pure ice, from which [Dan] was able to forcefully peel back the silicone mold without damaging the part. Next, the still-frozen part was freeze-dried for twenty hours, then finally treated in a vacuum sintering oven for twelve hours to make the final part. The video below the break shows the process. Continue reading “Freeze-drying For Improved Metal Printing” →

3D Printing Steel Parts At Home Via Special Filaments

August 11, 2021 by Lewin Day 31 Comments

Rocket engines are great for producing thrust from fire and fury, but they’re also difficult to make. They require high-strength materials that can withstand the high temperatures involved. [Integza], however, has tried for a long time to 3D print himself a working rocket engine. His latest attempt involves printing an aerospike design out of metal.

Even steel couldn’t hold up to the fury of the rocket exhaust!

The project relies on special metal-impregnated 3D printer filaments. The part can be printed with a regular 3D printer and then fired to leave just the metal behind. The filament can be harsh, so [Integza] uses a ruby nozzle to handle the metal-impregnated material. Processing the material requires a medium-temperature “debinding” stage in a kiln which removes the plastic, before a high-temperature sintering process that bonds the remaining metal particles into a hopefully-contiguous whole. The process worked well for bronze, though was a little trickier for steel.

Armed with a steel aerospike rocket nozzle, [Integza] attempts using the parts with his 3D printed rocket fuel we’ve seen before. The configuration does generate some thrust, and lasts longer than most of [Integza]’s previous efforts, though still succumbs to the intense heat of the rocket exhaust.

Overall, though, it’s a great example of what it takes to print steel parts at home. You’ll need a quality 3D printer, ruby nozzles and a controllable kiln, but it can be done. If you manage to print something awesome, be sure to drop us a line. Video after the break.

Continue reading “3D Printing Steel Parts At Home Via Special Filaments” →

HP Rolls Out Metal 3D Printers

September 14, 2018 by Al Williams 36 Comments

You normally think of HP as producing inkjet and laser printers. But they’ve been quietly building 3D printers aimed at commercial customers. Now they are moving out with metal printers called — predictably — the HP Metal Jet. The video (see below) is a little glitzy, but the basic idea is that print bars lay down powder on a 21-micron grid. A binding agent prints on the powder, presumably in a similar way to a conventional inkjet printer. A heat source then evaporates the liquid from the binder.

The process repeats for each layer until you remove the part and then sinter it using a third-party oven-like device. According to HP, their technique has more uniform material properties than fusing the powder on the bed with a laser. They also claim to be much faster than metal injection molding.

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Iro3d 3D Prints In Powdered Metal

January 15, 2018 by Al Williams 25 Comments

Printing with plastic and even resin is getting fairly common. Metal printing, though, is still in the realm of the exotic. A company called Iro3D is aiming to change that with a steel printer that you can buy in beta for about $5000. That seems steep when you can get plastic printers for under $200, but it is sheer bargain basement for something that can print in real metal.

Of course, there’s a catch. The printer doesn’t create a solid metal object right away. What it does is prepares a crucible using sand and metal powder. You then place the crucible in a kiln and what comes out is the final product. You can see a video review of their prototype machine, below from [3D Printing Nerd]. The company’s promotional video that shows a part coming out of the kiln is also below.

Continue reading “Iro3d 3D Prints In Powdered Metal” →

It’s Time For Direct Metal 3D-Printing

May 19, 2016 by Moritz Walter 75 Comments

It’s tough times for 3D-printing. Stratasys got burned on Makerbot, trustful backers got burned on the Peachy Printer meltdown, I burned my finger on a brand new hotend just yesterday, and that’s only the more recent events. In recent years more than a few startups embarked on the challenge of developing a piece of 3D printing technology that would make a difference. More colors, more materials, more reliable, bigger, faster, cheaper, easier to use. There was even a metal 3D printing startup, MatterFab, which pulled off a functional prototype of a low-cost metal-powder-laser-melting 3D printer, securing $13M in funding, and disappearing silently, poof.

This is just the children’s corner of the mall, and the grown-ups have really just begun pulling out their titanium credit cards. General Electric is on track to introduce 3D printed, FAA-approved fuel nozzles into its aircraft jet engines, Airbus is heading for 3D-printed, lightweight components and interior, and SpaceX has already sent rockets with 3D printed Main Oxidizer Valves (MOV) into orbit, aiming to make the SuperDraco the first fully 3D printed rocket engine. Direct metal 3D printing is transitioning from the experimental research phase to production, and it’s interesting to see how and why large industries, well, disrupt themselves.

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Pewter Casting With PLA

December 27, 2015 by Al Williams 12 Comments

Over on Hackaday.io, [bms.had] is showing his technique for 3D printing molds that he uses to cast (lead-free) pewter objects. The process looks simple enough, and if you have a 3D printer, you only need some lead-free pewter, a cheap toaster oven, and PLA filament. He’s made two videos (below) that do an excellent job of showing the steps required.

Even though the pewter is hot enough to melt the PLA, it doesn’t appear to be a major problem if you quench the piece fast enough. According to [bms.had], a slower quench will melt some PLA although that creates a smoother surface. You can see the 0.31 mm layer lines in the cast, though, although you can use any layer height you like to control that. Creating the mold is simple (the videos use Tinkercad, although anything suitable for creating 3D models would work). You essentially attach a funnel to your part and make the entire part a hole inside an enveloping shape.

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Metal 3D Printing With Your Printer

August 23, 2015 by Al Williams 23 Comments

Over in Italy, [Robotfactory] has a new setup called CopperFace that they claim allows you to essentially electroplate 3D printed objects with a metal coating using copper, nickel, silver, or gold.

We’ve talked about electroplating on plastic before, but that technique required mixing graphite and acetone. The CopperFace kit uses a conductive graphite spray and claims it deposits about 1 micron of plating on the object every two minutes.

We couldn’t help but wonder if the graphite spray is just the normal stuff used for lubricant. While the CopperFace’s electroplating tech seems pretty standard (copper sulfate and copper/phosphorus electrodes), we also wondered if some of the simpler copper acetate process we’ve covered before might be workable.

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