Building a Commodore 64 is among the easier projects for retrocomputing fans to tackle. That’s because the C64’s core chipset does most of the heavy lifting; source those and you’re probably 80% of the way there. But what if you can’t find those chips, or if you want more of a challenge than plugging and chugging? Are you out of luck?

Hardly. The video below from [DrMattRegan] is the first in a series on his scratch-built C64 that doesn’t use the core chipset, and it looks pretty promising. This video concentrates on building a replacement for the 6502 microprocessor — actually the 6510, but close enough — using just a couple of EPROMs, some SRAM chips, and a few standard logic chips to glue everything together. He uses the EPROMs as a “rulebook” that contains the code to emulate the 6502 — derived from his earlier Turing 6502 project — and the SRAM chips as a “notebook” for scratch memory and registers to make a Turing-complete random access machine.

[DrMatt] has made good progress so far, with the core 6502 CPU built on a PCB and able to run the Apple II version of Pac-Man as a benchmark. We’re looking forward to the rest of this series, but in the meantime, a look back at his VIC-less VIC-20 project might be informative.

Thanks to [Clint] for the tip.

In 2015, Tim Ellis and Jordan Noone founded Relativity Space around an ambitious goal: to be the first company to put a 3D printed rocket into orbit. While additive manufacturing was already becoming an increasingly important tool in the aerospace industry, the duo believed it could be pushed further than anyone had yet realized.

Rather than assembling a rocket out of smaller printed parts, they imagined the entire rocket being produced on a huge printer. Once the methodology was perfected, they believed rockets could be printed faster and cheaper than they could be traditionally assembled. What’s more, in the far future, Relativity might even be able to produce rockets off-world in fully automated factories. It was a bold idea, to be sure. But then, landing rockets on a barge in the middle of the ocean once seemed pretty far fetched as well.

Of course, printing something the size of an orbital rocket requires an exceptionally large 3D printer, so Relativity Space had to built one. It wasn’t long before the company had gotten to the point where they had successfully tested their printed rocket engine, and were scaling up their processes to print the vehicle’s propellant tanks. In 2018 Bryce Salmi, then an avionics hardware engineer at Relatively Space, gave a talk at Hackaday Supercon detailing the rapid progress the company had made so far.

Just a few years later, in March of 2023, the Relativity’s first completed rocket sat fueled and ready to fly on the launch pad. The Terran 1 rocket wasn’t the entirely printed vehicle that Ellis and Noone had imagined, but with approximately 85% of the booster’s mass being made up of printed parts, it was as close as anyone had ever gotten before.

The launch of Terran 1 was a huge milestone for the company, and even though a problem in the second stage engine prevented the rocket from reaching orbit, the flight proved to critics that a 3D printed rocket could fly and that their manufacturing techniques were sound. Almost immediately, Relativity Space announced they would begin work on a larger and more powerful successor to the Terran 1 which would be more competitive to SpaceX’s Falcon 9.

Now, after an administrative shakeup that saw Tim Ellis replaced as CEO, the company has released a nearly 45 minute long video detailing their plans for the next Terran rocket — and explaining why they won’t be 3D printing it.

Meet the New Boss

For the mainstream press, the biggest story has been that former Google chief Eric Schmidt would be taking over as Relativity’s CEO. Tim Ellis will remain on the company’s board, but likely won’t have much involvement in the day-to-day operation of the company. Similarly, co-founder Jordan Noone stepped down from chief technology officer to take on an advisory role back in 2020.

With the two founders of the company now sidelined, and despite the success of the largely 3D printed Terran 1, the video makes it clear that they’re pursuing a more traditional approach for the new Terran R rocket. At several points in the presentation, senior Relativity staffers explain the importance of remaining agile in the competitive launch market, and caution against letting the company’s historic goals hinder their path forward. They aren’t abandoning additive manufacturing, but it’s no longer the driving force behind the program.

For his part, The New York Times reports that Schmidt made a “significant investment” in Relativity Space to secure controlling interest in the company and his new position as CEO, although the details of the arrangement have so far not been made public. One could easily dismiss this move as Schmidt’s attempt to buy into the so-called “billionaire space race”, but it’s more likely he simply sees it as an investment in a rapidly growing industry.

Even before he came onboard, Relativity Space had amassed nearly $3 billion in launch contracts. Between his considerable contacts in Washington, and his time as the chair of the DoD’s Defense Innovation Advisory Board, it’s likely Schmidt will attempt to put Relativity the running for lucrative government launches as well.

All they need is a reliable rocket, and they’ll have a revenue stream for years.

Outsourcing Your Way to Space

In general, New Space companies like SpaceX and Rocket Lab have been far more open about their design and manufacturing processes than the legacy aerospace players. But even still, the video released by Relativity Space offers an incredibly transparent look at how the company is approaching the design of Terran R.

One of the most interesting aspects of the rocket’s construction is how many key components are being outsourced to vendors. According to the video, Relativity Space has contracted out the manufacturing of the aluminium “domes” that cap off the propellant tanks, the composite overwrapped pressure vessels (COPVs) that hold high pressure helium at cryogenic temperatures, and even the payload fairings.

This isn’t like handing the construction of some minor assemblies off to a local shop — these components are about as flight-critical as you can possibly get. In 2017, SpaceX famously lost one of their Falcon 9 rockets (and its payload) in an explosion on the launch pad due to a flaw in one of the booster’s COPVs. It’s believed the company ultimately brought production of COPVs in-house so they could have complete control of their design and fabrication.

Farming out key components of Terran R to other, more established, aerospace companies is a calculated risk. On one hand, it will allow Relativity Space to accelerate the booster’s development time, and in this case time is very literally money. The sooner Terran R is flying, the sooner it can start bringing in revenue. The trade-off is that their launch operations will become dependent on the performance of said companies. If the vendor producing their fairings runs into a production bottleneck, there’s little Relativity Space can do but wait. Similarly, if the company producing the propellant tank domes decides to raise their prices, that eats into profits.

For the long term security of the project, it would make the most sense for Relativity to produce all of Terran R’s major components themselves. But at least for now, the company is more concerned with getting the vehicle up and running in the most expedient manner possible.

Printing Where it Counts

In some cases, this is where Relativity is still banking on 3D printing in the long term. As explained in the video by Chief Technology Officer Kevin Wu, they initially planned on printing the propellant tank domes out of aluminum, but found that they couldn’t produce them at a fast enough rate to support their targeted launch cadence.

At the same time, the video notes that the state-of-the-art in metal printing is a moving target (in part thanks to their own research and development), and that they are continuing to improve their techniques in parallel to the development of Terran R. It’s not hard to imagine a point in the future where Relativity perfects printing the tank domes and no longer needs to outsource them.

While printing the structural components of the rocket hasn’t exactly worked out as Relativity hoped, they are still fully committed to printing the booster’s Aeon R engines. Printing the engine not only allows for rapid design iteration, but the nature of additive manufacturing makes it easy to implement features such as integrated fluid channels which would be difficult and expensive to produce traditionally.

Of course, Relativity isn’t alone in this regard. Nearly every modern rocket engine is using at least some 3D printed components for precisely the same reasons, and they have been for some time now.

Which in the end, is really the major takeaway from Relativity’s update video. Though the company started out with an audacious goal, and got very close to reaching it, in the end they’ve more or less ended up where everyone else in aerospace finds themselves in 2025. They’ll use additive manufacturing where it makes sense, partner with outside firms when necessary, and use traditional manufacturing methods where they’ve proven to be the most efficient.

It’s not as exciting as saying you’ll put the world’s first 3D printed rocket into space, to be sure. But it’s the path that’s the most likely to get Terran R on the launch pad within the next few years, which is where they desperately need to be if they’ll have any chance of catching up to the commercial launch providers that are already gobbling up large swaths of the market.

For the maker looking to turn their project into a business, trying to price your widget can be a bit of a conundrum. You want to share your widget with the world without going broke in the process. What if you could achieve both, letting the end user finish assembly? [PDF]

While over a decade has passed since Harvard Business School released this study on what they dub “The IKEA Effect,” we suspect that most of it will still be relevant given the slow pace of human behavior change. In short, when you make someone become part of the process of manufacturing or assembling their stuff, it makes them value it more highly than if it was already all put together in the box.

Interestingly, the researchers found “that consumers believe that their self-made products rival those of experts,” and that this is true regardless of whether these people consider themselves to be DIY enthusiasts or not. This only holds if the person is successful though, so it’s critical to have good instructions. If you have a mass market item in the works, you probably don’t want to require someone with no experience to solder something, but as IKEA has shown, nearly anybody can handle some hex screws and Allen wrenches.

If you’re looking for more advice on how to get your invention in people’s hands, how about this Supercon talk by Carrie Sundra about manufacturing on a shoestring budget or this video from Simone Giertz on her experiences with manufacturing from idea to finished product. You might want to steer clear of people promising patents for pennies on commercials, though.

Nanostructured metamaterials have shown a lot of promise in what they can do in the lab, but often have fatal stress concentration factors that limit their applications. Researchers have now found a strong, lightweight nanostructured carbon. [via BGR]

Using a multi-objective Bayesian optimization (MBO) algorithm trained on finite element analysis (FEA) datasets to identify the best candidate nanostructures, the researchers then brought the theoretical material to life with 2 photon polymerization (2PP) photolithography. The resulting “carbon nanolattices achieve the compressive strength of carbon steels (180–360 MPa) with the density of Styrofoam (125–215 kg m⁻³) which exceeds the specific strengths of equivalent low-density materials by over an order of magnitude.”

While you probably shouldn’t start getting investors for your space elevator startup just yet, lighter materials like this are promising for a lot of applications, most notably more conventional aviation where fuel (or energy) prices are a big constraint on operations. As with any lab results, more work is needed until we see this in the real world, but it is nice to know that superalloys and composites aren’t the end of the road for strong and lightweight materials.

We’ve seen AI help identify battery materials already and this seems to be one avenue where generative AI isn’t just about making embarrassing photos or making us less intelligent.

Fair warning: watching this hybrid manufacturing method for gear teeth may result in an uncontrollable urge to buy a fiber laser cutter. Hackaday isn’t responsible for any financial difficulties that may result.

With that out of the way, this is an interesting look into how traditional machining and desktop manufacturing methods can combine to make parts easier than either method alone. The part that [Paul] is trying to make is called a Hirth coupling, a term that you might not be familiar with (we weren’t) but you’ve likely seen and used. They’re essentially flat surfaces with gear teeth cut into them allowing the two halves of the coupling to nest together and lock firmly in a variety of relative radial positions. They’re commonly used on camera gear like tripods for adjustable control handles and tilt heads, in which case they’re called rosettes.

To make his rosettes, [Paul] started with a block of aluminum on the lathe, where the basic cylindrical shape of the coupling was created. At this point, forming the teeth in the face of each coupling half with traditional machining methods would have been tricky, either using a dividing head on a milling machine or letting a CNC mill have at it. Instead, he fixtured each half of the coupling to the bed of his 100 W fiber laser cutter to cut the teeth. The resulting teeth would probably not be suitable for power transmission; the surface finish was a bit rough, and the tooth gullet was a little too rounded. But for a rosette, this was perfectly acceptable, and probably a lot faster to produce than the alternative.

In case you’re curious as to what [Paul] needs these joints for, it’s a tablet stand for his exercise machine. Sound familiar? That’s because we recently covered his attempts to beef up 3D prints with a metal endoskeleton for the same project.

Thanks to [Ziggi] for the tip.