A bed of metal powder is visible through a green-tinted window. A fused metal pattern, roughly square, is visible, with one corner glowing white and throwing up sparks.

Printing In Metal With DIY SLM

January 3, 2026 by Aaron Beckendorf 5 Comments

An accessible 3D printer for metals has been the holy grail of amateur printer builders since at least the beginning of the RepRap project, but as tends to be the case with holy grails, it’s proven stubbornly elusive. If you have the resources to build it, though, it’s possible to replicate the professional approach with a selective laser melting (SLM) printer, such as the one [Travis Mitchell] built (this is a playlist of nine videos, but if you want to see the final results, the last video is embedded below).

Most of the playlist shows the process of physically constructing the machine, with only the last two videos getting into testing. The heart of the printer is a 500 Watt fiber laser and a galvo scan head, which account for most of the cost of the final machine. The print chamber has to be purged of oxygen with shielding gas, so [Travis] minimized the volume to reduce the amount of argon needed. The scan head therefore isn’t located in the chamber, but shines down into it through a window in the chamber’s roof. A set of repurposed industrial servo motors raises and lowers the two pistons which form the build plate and powder dispenser, and another servo drives the recoater blade which smooths on another layer of metal powder after each layer.

As with any 3D printer, getting good first-layer adhesion proved troublesome, since too much power caused the powder to melt and clump together, and too little could result in incomplete fusion. Making sure the laser was in focus improved things significantly, though heat management and consequent warping remained a challenge. The recoater blade was originally made out of printed plastic, with a silicone cord along the edge. Scraping along hot fused metal in the early tests damaged it, so [Travis] replaced it with a stainless steel blade, which gave much more consistent performance. The final results looked extremely promising, though [Travis] notes that there is still room for redesign and improvement.

This printer joins the very few other DIY SLM machines we’ve seen, though there is an amazingly broad range of other creative ideas for homemade metal printers, from electrochemical printers to those that use precise powder placement.

Continue reading “Printing In Metal With DIY SLM” →

A metal needle tip comes to a point against a white background. A scale bar in the lower left shows a 300 micrometer length.

Etching Atomically Fine Needle Points

October 13, 2025 by Aaron Beckendorf 23 Comments

[Vik Olliver] has been extending the lower resolution limits of 3D printers with the RepRapMicron project, which aims to print structures with a feature size of ten micrometers. A molten plastic extruder would be impractical at such small scales, even if a hobbyist could manufacture one small enough, so instead [Vik]’s working on a system that uses a very fine needle point to place tiny droplets of UV resin on a substrate. These points have to be sharper than anything readily available, so his latest experiments have focused on electrochemically etching his own needles.

The needles start with a fine wire, which a 3D-printed bracket holds hanging down into a beaker of electrolyte, where another electrode is located. By applying a few volts across the circuit, with the wire acting as an anode, electrochemical erosion eventually wears through the wire and it drops off, leaving an atomically sharp point. Titanium wire performs best, but Nichrome and stainless steel also work. Copper wire doesn’t work, and by extension, nor does the plated copper wire sometimes sold as “stainless steel” by sketchy online merchants.

The electrolyte was made from either a 5% sodium chloride solution or 1% nitric acid. The salt solution produced a very thin, fine point, but also produced a cloudy suspension of metal hydroxides around the wire, which made it hard to tell when the wire had broken off. The goal of nitric acid was to prevent hydroxide formation; it produced a shorter, blunter tip with a pitted shaft, but it simply etched the tip of the wire to a point, with the rest of the wire never dropping off. Some experimentation revealed that a mixture of the two electrolyte solutions struck a good balance which etched fine points like the pure salt solution, but also avoided cloudy precipitates.

If you’re interested in seeing more of the RepRapMicron, we’ve looked at a previous iteration which scribed a minuscule Jolly Wrencher in marker ink. On a more macro scale, we’ve also seen one 3D printer which used a similar resin deposition scheme.

A camera-based microscope is on a stand, looking down towards a slide which is held on a plastic stage. The stage is held in place by three pairs of brass rods, which run to red plastic cranks mounted to three stepper motors. On the opposite side of each crank from the connecting rod is a semicircular array of magnets.

Designing An Open Source Micro-Manipulator

September 4, 2025 by Aaron Beckendorf 21 Comments

When you think about highly-precise actuators, stepper motors probably aren’t the first device that comes to mind. However, as [Diffraction Limited]’s sub-micron capable micro-manipulator shows, they can reach extremely fine precision when paired with external feedback.

The micro-manipulator is made of a mobile platform supported by three pairs of parallel linkages, each linkage actuated by a crank mounted on a stepper motor. Rather than attaching to the structure with the more common flexures, these linkages swivel on ball joints. To minimize the effects of friction, the linkage bars are very long compared to the balls, and the wide range of allowed angles lets the manipulator’s stage move 23 mm in each direction.

To have precision as well as range, the stepper motors needed closed-loop control, which a magnetic rotary encoder provides. The encoder can divide a single rotation of a magnet into 100,000 steps, but this wasn’t enough for [Diffraction Limited]; to increase its resolution, he attached an array of alternating-polarity magnets to the rotor and positioned the magnetic encoder near these. As the rotor turns, the encoder’s local magnetic field rotates rapidly, creating a kind of magnetic gear.

A Raspberry Pi Pico 2 and three motor drivers control this creation; even here, the attention to detail is impressive. The motor drivers couldn’t have internal charge pumps or clocked logic units, since these introduce tiny timing errors and motion jitter. The carrier circuit board is double-sided and uses through-hole components for ease of replication; in a nice touch, the lower silkscreen displays pin numbers.

To test the manipulator’s capabilities, [Diffraction Limited] used it to position a chip die under a microscope. To test its accuracy and repeatability, he traced the path a slicer generated for the first layer of a Benchy, vastly scaled-down, with the manipulator. When run slowly to reduce thermal drift, it could trace a Benchy within a 20-micrometer square, and had a resolution of about 50 nanometers.

He’s already used the micro-manipulator to couple an optical fiber with a laser, but [Diffraction Limited] has some other uses in mind, including maskless lithography (perhaps putting the stepper in “wafer stepper”), electrochemical 3D printing, focus stacking, and micromachining. For another promising take on small-scale manufacturing, check out the RepRapMicron.

Continue reading “Designing An Open Source Micro-Manipulator” →

Jolly Wrencher Down To The Micron

April 21, 2025 by Ian Bos 6 Comments

RepRap was the origin of pushing hobby 3D printing boundaries, and here we see a RepRap scaled down to the smallest detail. [Vik Olliver] over at the RepRap blog has been working on getting a printer working printing down to the level of micron accuracy.

The printer is constructed using 3D printed flexures similar to the OpenFlexure microscope. Two flexures create the XYZ movement required for the tiny movements needed for micron level printing. While still in the stages of printing simple objects, the microscopic scale of printing is incredible.

Continue reading “Jolly Wrencher Down To The Micron” →

Ask Hackaday, What’s Next?

September 6, 2024 by Jenny List 39 Comments

Writing for Hackaday involves drinking from the firehose of tech news, and seeing the latest and greatest of new projects and happenings in the world of hardware. But sometimes you sit back in a reflective mood, and ask yourself: didn’t this all used to be more exciting? If you too have done that, perhaps it’s worth considering how our world of hardware hacking is fueled, and what makes stuff new and interesting.

Hardware projects are like startup fads

An AliExpress page of Nixie clock kits — When AliExpress has hundreds of kits for them, Nixie clocks are a mature project sector, by any measure.

Hardware projects are like startup fads, they follow the hype cycle. Take Nixie clocks for instance, they’re cool as heck, but here in 2024 there’s not so much that’s exciting about them. If you made one in 2010 you were the talk of the town, in 2015 everyone wanted one, but perhaps by 2020 yours was simply Yet Another Nixie Clock. Now you can buy any number of Nixie clock kits on Ali, and their shine has definitely worn off. Do you ever have the feeling that the supply of genuinely new stuff is drying up, and it’s all getting a bit samey? Perhaps it’s time to explore this topic.

I have a theory that hardware hacking goes in epochs, each one driven by a new technology. If you think about it, the Arduino was an epoch-defining moment in a readily available and easy to use microcontroller board; they may be merely a part and hugely superseded here in 2024 but back in 2008 they were nothing short of a revolution if you’d previously has a BASIC Stamp. The projects which an Arduino enabled produced a huge burst of creativity from drones to 3D printers to toaster oven reflow and many, many, more, and it’s fair to say that Hackaday owes its early-day success in no small part to that little board from Italy. To think of more examples, the advent of affordable 3D printers around the same period as the Arduino, the Raspberry Pi, and the arrival of affordable PCB manufacture from China were all similar such enabling moments. A favourite of mine are the Espressif Wi-Fi enabled microcontrollers, which produced an explosion of cheap Internet-connected projects. Suddenly having Wi-Fi went from a big deal to built-in, and an immense breadth of new projects came from those parts. Continue reading “Ask Hackaday, What’s Next?” →

Hackaday Podcast Episode 262: Wheelchair Hacking, Big Little Science At Home, Arya Talks PCBs

March 15, 2024 by Tom Nardi No comments

Join Hackaday Editors Elliot Williams and Tom Nardi as they go over their favorite hacks and stories from the past week. This episode starts off with an update on Hackaday Europe 2024, which is now less than a month away, and from there dives into wheelchairs with subscription plans, using classic woodworking techniques to improve your 3D printer’s slicer, and a compendium of building systems. You’ll hear about tools for finding patterns in hex dumps, a lusciously documented gadget for sniffing utility meters, a rare connector that works with both HDMI and DisplayPort, and a low-stress shortwave radio kit with an eye-watering price tag. Finally, they’ll take a close look at a pair of articles that promise to up your KiCAD game.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download in DRM-free MP3.

Continue reading “Hackaday Podcast Episode 262: Wheelchair Hacking, Big Little Science At Home, Arya Talks PCBs” →

Hackaday Prize 2023: Ending 10 Years On A High Note

November 7, 2023 by Tom Nardi 18 Comments

It’s a fact of life — all good things must eventually come to an end. The trick is not to focus so much on the chapter that’s closing, but look ahead to what comes next. This is precisely how the Hackaday Prize ended its incredible ten-year run on Saturday during Supercon.

This final year of the competition saw some of the most impressive entries we’ve ever had, leaving us with five exceptionally promising winners. These projects exemplify the qualities that the Hackaday Prize was designed to seek out and amplify and make a perfect capstone for this grand experiment in philanthropic hacking.

Continue reading “Hackaday Prize 2023: Ending 10 Years On A High Note” →