Even if you haven’t been here for very long, you’ll probably recognize Quinn Dunki as Hackaday’s resident consulting machinist. Quinn recently did a great series of articles on the “King of Machine Tools”, the lathe, covering everything from the history of precision machine tools to making your first chips. She’s documented the entire process of procuring and setting up a new lathe, pointing out all the potential pitfalls the budding home machinist may face. You can get a much deeper dive into her machining adventures on her YouTube channel, Blondihacks.
Flinging hot metal chips around is hardly all Quinn has accomplished, though. Long before her foray into machine tools, there was Veronica, a scratch-built 6502 machine Quinn created as an homage to the machines that launched her into a life of writing software. We’ve featured Veronica on our pages a couple of times, and she’s always made quite a hit.
Please join us for this Hack Chat, where we’ll discuss:
How developing software and machining are alike, and how they differ;
How social networks have changed the perception of machining;
Best practices for getting started in machining; and
Are there any new machine tool purchases in the pipeline?
You are, of course, encouraged to add your own questions to the discussion. You can do that by leaving a comment on the Home Machine Shop Hack Chat and we’ll put that in the queue for the Hack Chat discussion.
Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
In case you haven’t been reading Hackaday for the last few weeks, we just had an amazing 10th anniversary party in Pasadena this weekend, full of workshops, talks, and a party that reportedly went until four in the morning. One of the amazing hackers we invited to give a talk was [Quinn Dunki], creator of Veronica, the modern 6502 computer stuffed inside an old radio.
We first saw Veronica a few years ago, but [Quinn] figures she’s been building her computer for about five years now. She’s a software developer by trade that decided one day to dip her toes into the murky seas of hardware development and build a computer from the ground up. She chose the 6502 as the brains of her contraption, laid out everything on single-sided boards etched in a kitchen, and connected everything with a backplane. Right now it has a USB keyboard, (technically a PS/2 keyboard with a USB plug), NES controllers, a VGA display, and a monitor and Pong in ROM. [Quinn]’s goal was to build a computer that could program itself, and after five years, she’s accomplished that goal.
[Quinn] admits her software background was responsible for a few of her admittedly bad design choices; the VGA is generated by an ATMega microcontroller, working under the theory that if she could clock the micro fast enough, she could do VGA. She now believes an FPGA would have been a better choice for video output, but now that the video circuit is done, she probably won’t revisit that problem.
There is one thing missing from Veronica, and something that [Quinn] will be working on in the future: mass storage. Right now every program Veronica can run is either stored in ROM or entered via the keyboard. A hard drive is the next problem to solve, either with an SD card, or a Compact Flash or IDE hard drive.
By this point we are all familiar with [Quinn Dunki] and her awesome engineering and retro hacking. [Quinn] aims her latest blog post at the Apple IIc Plus and its tone deaf bleeping beep. You can hear it for yourself in her beep comparison video after the break.
[Quinn] gets straight into the source code as expected and works through a logical process that she explains quite nicely while looking for the origin of the problem. There are some interesting and hard to follow moves in the source as control jumps around the ROM(s) all in the name of minimizing RAM. In proper form [Quinn] uses the ROM bank switching ability to her advantage as she see’s [the Woz’s] efficiency and raises him some fancy footwork of her own along with a beep that doesn’t make our skin crawl.
[Quinn Dunki] is adding wireless audio to all of the rooms in her home. She’s going with Airplay, snatching up used or refurbished Airport Express units because of their ability to work with both her existing WiFi and the Airplay protocol. The last piece in the puzzle is to get an Amp and she chose the small unit seen above. The problem is that it was dead on arrival and she couldn’t get the company to respond to her issue. So she cracked it open and fixed it right up.
The offenders are the three electrolytic capacitors at the top of the picture. She took some close-up images of each and you can’t miss the fact that they’re blown out. These are often among the higher price-per-unit parts and manufactures try to pinch the penny as much as possible. Add to it the heat in a small enclosure like this one and you’ve got a failure. [Quinn] dug through her junk bin but the size of the replacement had to be a perfect match so she ended up putting in a parts order. The new caps fit and work perfectly as you can hear in the clip after the break.
All it takes is one knucklehead to go and do something stupid to screw things up for everyone. We’re not exactly sure who the knucklehead is behind the recent ban on hexamine fuel tablets, but given that it’s now proscribed in the UK under the “Control of Poisons and Explosives Precursors Regulations 2023,” we expect that that story is a doozy.
So what’s hexamine, and why should we care if it’s banned? As [Markus Bindhammer] explains, hexamine is a solid fuel commonly used to power model steam engines, among myriad other uses. Its ban leaves a bit of a hole in the model steam community, which [Markus] seeks to fill with this quick and easy gel fuel chemistry project.
The “California Snowball” is a homebrew version of what’s in those solid fuel cans you see heating chafing pans at catered events, with one common brand being Sterno. [Markus] used a saturated solution of calcium acetate (6 g in 50 ml of water) and added that to 150 ml of ethanol; commercial formulations usually use methanol to prevent anyone from drinking the stuff, with varying degrees of success. The calcium acetate forms a gel that looks like whipped cream and traps the ethanol inside. The gel can be easily scooped up and spread around, and burns with a clean, smokeless flame.
It may not exactly be a “plug and play” replacement for hexamine tablets, but one does what one can. And if there’s one thing we can celebrate about model steam engineers, it’s their persistence. We got a bunch of them together last year for a Hack Chat with [Quinn Dunki], and their passion for making things move with steam was pretty impressive.
Ask the average person about steam power and they’ll probably imagine a bygone era, a time when the sky was thick with smoke belched out by coal-burning locomotives and paddle-wheel ships. Steam is ancient technology they’ll say, and has as much to do with modern living as the penny-farthing.
Naturally, the real story is a bit more complex than that. Sure the reciprocating steam engine has fallen out of favor as a means of propulsion, but the concept of running machinery with steam is alive and well. In fact, unless you’re running on wind or solar power, there’s an excellent chance that a steam turbine is responsible for keeping the lights on in your house.
In honor of all things steam, we invited Quinn Dunki to host this week’s Hack Chat. Those who follow her exploits on YouTube will know that over the last several years she’s built a number of steam engines, from miniature scratch-built models to commercial kits that can do useful work. Who better to answer your burning steaming questions?
The first questions in the Chat were logical enough, with several users wanting to know just how hard it is to build a functional steam engine if you don’t have access to a mill or other means of high precision machining. According to Quinn, while better equipment will certainly allow you to build a more powerful and efficient engine, the basic premise is so simple that it doesn’t take much to get one going. If you’ve got a mini lathe and some bar stock, you’re half way there. In fact, they are so forgiving that she opines you’d struggle to build a steam engine that didn’t at least turn over — though that doesn’t mean it will necessarily run well.
Naturally some comparisons were drawn between the complexity of building a steam engine and putting together a small internal combustion engine (ICE). But while they might seem conceptually similar, Quinn cautions that building a working ICE from scratch is far more difficult and dangerous. She explains that steam engines have a tendency to fail gracefully, that is, mistakes in the design or poor tolerances generally result in little worse than wasted steam and extra noise. Comparatively, a faulty ICE design could easily turn into a bomb on your workbench.
Of course, that’s not to say working with steam is without danger. You certainly don’t want to underestimate high pressure steam, which is why boilers that are over 6 in (15 cm) in diameter or that produce more than 100 PSI will often require the operator to be licensed. They may also need to be inspected, though Quinn notes that your local government official probably won’t be able to make heads or tails of your homebrew build — so if you need an official stamp of approval, your best bet is to find a local model engineering club or society that would have the appropriate connections. All that being said, most hobbyists make it a point to try and get their engine running at the lowest pressure possible, so unless you’ve got something really massive in mind, you’ll probably never need to build up more than 60 PSI or so.
A DIY electric boiler and small steam engine.
Another topic of discussion was how to fuel the boiler itself. An electrically powered boiler is perhaps the easiest option, but is somewhat counterproductive if you hope to put your steam engine to useful work. Coal and wood fires are an option, and indeed were commonly used in the old days, but the soot and ash they produce can be a problem.
Quinn also notes that if you’re using such fuels, you need a way to quickly remove the firebox from the boiler in an emergency; something she likens to the starship Enterprise having to eject its warp core before it explodes. For her own projects, Quinn says she uses either an electric element or a camping gas burner.
While most of the questions during this Hack Chat had to do with the work Quinn has already featured on her blog and YouTube channel, naturally there were questions about where things go from here. After she completes the steam engine kit she’s working on currently, she says she’ll likely to back to another scratch-built engine. She also plans on coupling some of her engines to generators, as she’s gotten many requests about seeing these machines put to useful work. Looking further ahead Quinn says she’s interested in casting her own bronze and aluminum components, and specifically wants to work with “lost PLA” casting, which is a variant of lost wax casting that uses a mold based on a 3D printed part.
We’d like to thank Quinn Dunki for stopping by the Hack Chat and sharing some insights into this unique hobby. While a handcrafted boiler or a desktop steam reciprocating engine might not be on the average Hackaday reader’s list of future projects, it’s still fascinating to see how they work. We owe much of our modern life to steam power, so the least we can do is show it some respect.
The Hack Chat is a weekly online chat session hosted by leading experts from all corners of the hardware hacking universe. It’s a great way for hackers connect in a fun and informal way, but if you can’t make it live, these overview posts as well as the transcripts posted to Hackaday.io make sure you don’t miss out.
The steam power age may be behind us now, but that doesn’t mean that the engineering that went into steam engines isn’t worth exploring. In a lot of ways, the steam age is what made modern engineering what we know it as today. Where wind- and water-powered devices could often work well enough with a couple of inches of tolerance, steam engines required parts measured to the hundredth or even thousandth of an inch. Optimizing steam engines required a deep understanding of thermodynamics, too, which unveiled more about the way the universe works than had ever been realized before. And the need for parts strong enough to withstand steam pressure and the lubricants needed to keep the wheels turning paved the way for advances in materials science and chemical engineering that are still paying dividends today.
Celebrating the achievements of steam power may seem anachronistic, but in light of everything steam has done for us, it makes a lot of sense. And that’s not to mention the cool aesthetics of steam engines, with beefy castings and brass parts sliding back and forth, complicated linkages doing who-knows-what to make the engine work on nothing more than a little bit of boiling water. There’s the attraction of danger, too; improperly built boilers can be a disaster, so building one that’s safe to use can be quite a challenge.
All this and more is what the steam hobby is all about, an area that Quinn Dunki has been exploring for a while now. Over on her YouTube channel, Quinn has documented the process of turning raw metal into a working steam engine and boiler, and is currently working on a bigger, more powerful engine. We’ve invited her on the Hack Chat to talk about all things steam — where to get started in the hobby, what kinds of things you can learn by building your own steam engines, and how her current builds are going. If you’ve ever wanted to explore steam power, here’s your chance to ask a real steam aficionado.
Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, March 20, at noon, Pacific time. If time zones have got you down, we have a handy time zone converter.
