Recreating Damascus steel remains a holy grail of materials science. The exact process and alloys used are long ago lost to time. At best, modern steelworking methods are able to produce a rough visual simulacra of sorts that many still consider to be pretty cool looking. Taking a more serious bent at materials science than your average knifemaker, a group of scientists at the Max Planck institute have been working to create a material with similar properties through 3D printing.
The technology used is based on the laser sintering of metal powders. In this case, the powder consists of a mixture of iron, nickel and titanium. The team found that by varying the exact settings of the laser sintering process on a layer-by-layer basis, they could create different microstructures throughout a single part. This allows the creation of parts that are ductile, while remaining hard enough to be sharpened – a property which is useful in edged weapons like swords.
While the process is nothing like that used by smiths in Damascus working with Wootz steel, the general idea of a metal material with varying properties throughout remains the same. For those eager to get into old-school metalwork, consider our articles on blacksmithing. For those interested in materials research, head to a good university. Or, better yet – do both!
In The Room Three, players are tasked with collecting mysterious objects known as “Null Shards”. But it seems one player, who goes by the name [Juiceman], took this challenge a bit literally. Starting with promotional art released for the game, he embarked on an epic journey to create a replica “Null Shard” that ended up looking so good that one of them is currently residing in a place of honor at the headquarters of developer Fireproof Games.
The developers had previously released image files to create a papercraft version of the Null Shard on their website, so [Juiceman] based his initial CAD work on these designs. But it turned out the surface texture was a little too complex to laser etch into acrylic without making a soupy mess. He simplified it a bit, while trying to retain the overall effect. From the superb laser-etched acrylic master he made a silicone mold started casting the eight triangular panels needed for two copies of the Shard.
To hold it all together [Juiceman] create a “skeleton” pyramid by first experimenting with designs on a traditional plastic FDM printer. After a few tries he had a workable design and switched over to a laser sintering machine, giving the final frame a gorgeous texture. With the cast panels installed and a few coats of paint, he had his Null Shards.
The final step was to turn down a piece of ash to make a nice base, and 3D print the feet and “claw” mount for the Shard using the same laser sintering process. The finished product looks fantastic, and apparently lives on a shelf next to a similarly constructed replica of the “Lament Configuration” puzzle cube from the Hellraiser films. [Juiceman] says the two replicas are the first entries into his “Geometries of Hell” collection, which incidentally, we’ve decided will officially be the name of our first metal album. All we need to do now is learn how to play instruments.
While the jury is still out on 3D printing for the consumer market, there’s little question that it’s becoming a major part of next generation manufacturing. While we often think of 3D printing as a way to create highly customized one-off objects, that’s a conclusion largely based on how we as individuals use the technology. When you’re building something as complex as a rocket engine, the true advantage of 3D printing is the ability to not only rapidly iterate your design, but to produce objects with internal geometries that would be difficult if not impossible to create with traditional tooling.
So it’s no wonder that key “New Space” players like SpaceX and Blue Origin make use of 3D printed components in their vehicles. Even NASA has been dipping their proverbial toe in the additive manufacturing waters, testing printed parts for the Space Launch System’s RS-25 engine. It would be safe to say that from this point forward, most of our exploits off of the planet’s surface will involve additive manufacturing in some capacity.
But one of the latest players to enter the commercial spaceflight industry, Relativity Space, thinks we can take the concept even farther. Not content to just 3D print rocket components, founders Tim Ellis and Jordan Noone believe the entire rocket can be printed. Minus electrical components and a few parts which operate in extremely high stress environments such as inside the pump turbines, Relativity Space claims up to 95% of their rocket could eventually be produced with additive manufacturing.
If you think 3D printing a rocket sounds implausible, you aren’t alone. It’s a bold claim, so far the aerospace industry has only managed to print relatively small rocket engines; so printing an entire vehicle would be an exceptionally large leap in capability. But with talent pulled from major aerospace players, a recently inked deal for a 20 year lease on a test site at NASA’s Stennis Space Center, and access to the world’s largest metal 3D printer, they’re certainly going all in on the idea. Let’s take a look at what they’ve got planned.
Last week I went to the International Manufacturing Technology Show (IMTS) and it was incredible. This is a toy store for machinists and showcases the best of industrial automation. But one of the coolest trends I found at the show are all the techniques used to 3D print in metal. The best part is that many of the huge machines on display are actually running!
It’s probably better to refer to this as additive manufacturing, because the actual methods can be significantly different from your 3D printer. Below you’ll find examples of three different approaches to this process. I had a great interview with a company doing actual 3D printing in metal using a nozzle-based delivery often called cladding. There’s a demo video of powder layer printing using lasers. And a technique that uses binders as an intermediary step toward the final metal part. Let’s take a look!
Formlabs have just announced the Fuse 1 — a selective laser sintering (SLS) 3D printer that creates parts out of nylon. Formlabs is best known for their Form series of resin-based SLA 3D printers, and this represents a very different direction.
SLS printers, which use a laser to sinter together models out of a powder-based material, are not new but have so far remained the domain of Serious Commercial Use. To our knowledge, this is the first time an actual SLS printer is being made available to the prosumer market. At just under 10k USD it’s definitely the upper end of the prosumer market, but it’s certainly cheaper than the alternatives.
The announcement is pretty light on details, but they are reserving units for a $1000 deposit. A few things we can throw in about the benefits of SLS: it’s powder which is nicer to clean up than resin printers, and parts should not require any kind of curing. The process also requires no support material as the uncured powder will support any layers being cured above it. The Fuse 1’s build chamber is 165 x 165 x 320 mm, and can be packed full of parts to make full use of the volume.
In the past we saw a detailed teardown of the Form 2 which revealed excellent workmanship and attention to detail. Let’s hope the same remains true of Formlabs’ newest offering.
We are all used to Fused Deposition Modeling, or FDM, 3D printers. A nozzle squirts molten material under the control of a computer to make 3D objects. And even if they’re usually rather expensive we’re used to seeing printers that use Stereolithography (SLA), in which a light-catalysed liquid monomer is exposed layer-by layer to allow a 3D object to be drawn out. The real objects of desire though are unlikely to grace the average hackspace. Selective Laser Sintering 3D printers use a laser on a bed of powder to solidify a 3D object layer by layer.
While an SLS printer may be a little beyond most budgets, it turns out that it’s not impossible to experiment with the technology. [William Osman] has an 80 W laser cutter, and he’s been experimenting with it sintering beach sand to create 2D objects. His write-up gives a basic introduction to glassmaking and shows the difference between using sand alone, and using sodium carbonate to reduce the melting point. He produces a few brittle barely sintered tests without it, then an array of shapes including a Flying Spaghetti Monster with it.
The results are more decorative than useful at the moment, however it is entirely possible that the technique could be refined. After all, this is beach sand rather than a carefully selected material, and it is quite possible that a finer and more uniform sand could give better results. He says that he’ll be investigating its use for 3D work in the future.
We’ve put his video of the whole process below the break, complete with worrying faults in home-made laser wiring. It’s worth a watch.
Filament printers are here to stay, and in the past year there have been a number of SLA and DLP resin printers that can create objects at mind-boggling high resolutions. Both of these technologies have their place, but printing really complex objects without also printing supports is out of the question.
[Brandon] has been working to create an open source printer using a different technology, selective laser sintering. That’s a laser melting tiny particles of stuff to create an object. This printer can work with any material that can be turned into a powder and melted by a laser, and also has the neat bonus of printing without any supports.
[Brandon]’s printer, Ester, uses small meltable polyester dust as both a print material and support structure. The object to be printed is created by shining a laser over a bed filled with polyester, drawing one layer, and putting another small layer of material over the previous layer.
The machine is using a diode laser, with a few experiments with a 1 Watt diode providing some very nice parts. The mechanics of the machine were built at [Brandon]’s local TechShop, and already he has an IndieGoGo for future development and a $3000 development kit. That’s a bit expensive as far as project printers go, but SLS is an expensive technology to get right; ‘pro’ SLS printers are in the hundreds of thousands of dollars.