This excellent content from the Hackaday writing crew highlights recurring topics and popular series like Linux-Fu, 3D-Printering, Hackaday Links, This Week in Security, Inputs of Interest, Profiles in Science, Retrotechtacular, Ask Hackaday, Teardowns, Reviews, and many more.
Most of modern society’s energy usage is spent on heating in some form, whether it is to heat water, raise the temperature in a room, or for use in industrial processes. This makes it an excellent target for improvements in efficiency and resilience, as well as in the effort to decarbonize the world’s energy production. Here district heating and similar solutions are likely to play a major role in the near future.
Over the past decades, a number of nations have either already built out extensive district heating grids, or are in the process of doing so. The main advantage of these heating grids is that they not only allow for more efficient, centralized generating of heat, but also allow for e.g. industrial waste heat to be used productively rather than wasted, even if most of the heat will come from either dedicated or cogeneration thermal plants.
Recently, district heating has received a big push in e.g. China in the form of nuclear cogeneration, while the potential of using thermal storage to buffer heat for later use along with the concept of tying data centers into heating grids are also being explored. Although district heating is hardly new, it may help to ease humanity into a low-carbon future, without losing a bit of comfort.
If your friend told you their car had a backup camera, a digital dashboard, climate control, could scan for radio stations, and even helped stay on the road, you wouldn’t think much about it. Unless the year was 1969. The car — the Hurricane by Australian automaker Holden — was never a production vehicle. But it was way beyond the state of the art in 1969 and isn’t too dated, even today. The concept car was actually found in 1988 and restored by 2011. Honestly, it still looks great.
The car looks amazing and was meant to be a research vehicle and — probably — nice eye candy for the car shows. Seating two passengers with a mid-mounted 253 cubic inch V8, it featured many things we take for granted now: a backup camera, temperature control, and a (somewhat) digital dashboard, for example. There was a system to help it stay in lane, but that required magnets in the road — it was 1969, after all.
The fiberglass body was unique and had a canopy instead of doors. The power seats lifted up when the canopy came up and went down for driving. The passenger compartment was a steel cage. The vehicle featured headrests, a foam-lined fuel tank, and a fire warning system. Two of the brakes were even oil-cooled.
Wow! I can’t believe it already came and went — but the first annual (semi-annual?) Kansas City Keyboard Meetup was, in my opinion, a rousing success. And I think organizer and Discord-nominated god among men [Ricardo] agrees with me. (He does; I checked before we left the venue.)
First of all, the attendance was off the charts, perhaps thanks in part to our announcement last week. We aim to get you the news sooner next time, in case you want to come in from surrounding states and municipalities. RSVPs sat around 20-something, and then shot up to 60 or so in the days leading up. Fortunately, there were enough tiny sandwiches, granola bars, and s t i c k e r s to go around. I already put mine on my keebin’ toolbox.
The Hive Was Buzzing
The event took place at Hive Co-Working thanks to [Nick], and overall, the space turned out to be a good layout. We were set up right inside the windows looking out to the street, and I like to think that we drew in a few passers-by, though I am probably more than a little bit biased. I wondered aloud on the way home how a sandwich board out on the sidewalk would have affected the influx of randos.
My husband pointed out that even though we were all the way downtown, this is Kansas City and not New York City, and most of the keyboard enthusiasts about town were already accounted for. Hmpf. I still say we should try a sandwich board next time. We could go meta and mention the tiny sandwiches inside. Don’t worry — there was plenty of sanitizer and napkins to go around, plus a box of gloves.
A couple of years ago we published a look at precision measurement tools, in particular vernier calipers and micrometer screw gauges. It featured a look at how they work and how they’re used, and a comparison of good and bad quality instruments. When comparing micrometers we had three of them, a Mitutoyo and a Moore & Wright representing decent quality, and an £8 ($9.41) Daniu from Banggood from the cheaper end of the market. As you might expect, the Daniu was laughably bad, with noticeable play in its thread and jaws that were not parallel to the extent you could see light between them. You might consider it case closed for cheap micrometers then, were it not that while on my summer travels through the Benelux countries I spied a Parkside micrometer in a Lidl supermarket for €8.99 ($8.92). I had to buy it and investigate.
Some Measuring Devices With Your Groceries?
Lidl is a German supermarket chain that can be found all over Europe, and like their arch-competitor Aldi they feature the “Middle of Lidl” aisles full of all sorts of useful stuff that changes on a regular basis. Among this is a comprehensive range of tools under the Parkside brand, which is basically on par with the good stuff from Harbor Freight, and are in fact quite good for the price. Thus even though it’s about the same price as the Daniu I had higher expectations for the Parkside micrometer.
The micrometer is packaged in the usual plastic case in a small cardboard box, and comes with a large paper instruction sheet and a small spanner for zero adjustment. Taking it out of the case, it follows exactly as you’d expect from a micrometer with a solid drop-forged frame and an aluminium barrel on the micrometer head. It can measure up to 25 mm at a resolution of 0.01 mm, exactly like the others I tested in 2020. So my nine dollars or so has got me a micrometer, but is it any good? How do you evaluate a micrometer screw gauge? I re-borrowed the two comparison instruments from 2020, and set out to find out.
The Tiniest Sliver Of Light Gives It Away
The mirror finish on the Mitutoyo jaw face reflecting the “H” of the Hackaday website.
It’s worth saying that the jaw faces are polished, but not to a mirror finish as those on the Mitutoyo and neither do they appear to have been hardened. In the first instance, comparing with the Daniu I closed the jaws against the force of the ratchet, and held it up against the light to spot any imperfections in the way they meet. Against the blue sky through my window I couldn’t see any, but a friend did the same thing against the more intense point source of an electric light and indeed there was the tiniest discernable sliver of light. Not the obvious wedge of light I caught with the Daniu back in 2020 and less than the visible sliver of light when it is measuring a human hair, but definitely enough to knock a few hundredths of a milimetre off my trust in its accuracy.
The next step in the evaluation involves opening the jaws about half way, and feeling for any play in the thread. None discernable, at least one win over the Daniu which had the barrel flapping around with significant play. Then a zero test, after adjusting the zero position with the spanner a few repeated closings with the ratchet, to check that it always returns to the same zero point. In this case as with all micrometers it’s possible to overshoot the zero and damage the thread if you apply too much force, but just on the ratchet it would land in the same place. A pass on a couple of tests then, so while it’s not the worst micrometer ever it’s obvious that the low price brings at least one compromise.
A Tiny Discrepancy In Measurement
Opening up the three micrometers from the 2020 piece again it’s immediately obvious in the silky feel of the thread and the lack of wobble in the ratchet just where the money goes in an expensive micrometer, and just how comedically bad the Daniu was by comparison. But it’s the Parkside in our sights today, so it’s time to make a few comparitive measurements between it and the Mitutoyo. First up were the old standbys of a piece of paper and a human hair in which the Parkside returned the same as the Mitutoyo, and then the machined shaft of the Moore & Wright which returned a difference of 0.01 mm.
Parkside
Mitutoyo
Sheet of paper
0.12 mm
0.12 mm
Human hair
0.05 mm
0.05 mm
Moore & Wright shaft
6.79 mm
6.80 mm
The discrepancy in this table when measuring the shaft may be small, but it harks back to that sliver of light from imperfectly aligned jaws. As expected if the shaft meets the jaws at anything but the highest point of the jaw it will return a slightly smaller reading, thus it immediately has an error on everything it returns. Discussing it with friends there was raised the intriguing possibility of lapping the faces by drawing a sheet of exceptionally fine abrasive through the closed jaws, however I have my doubts as to whether this would do anything but make the gap worse.
What I can say about the Parkside micrometer screw gauge is that it appears reasonably well-built, but I can’t present it as the equal of the more expensive instruments when its faces are anything but parallel. I would say therefore that it would be good for basic measurements when machining or in CAD work where an error of 0.01 mm or 0.02 mm wouldn’t matter too much, but perhaps I wouldn’t quite trust it when working with extremely fine tolerances. Still, it’s not the worst among cheap micrometers and it’s on sale for a very reasonable price even if it’s not in the same precision instrument league as the Mitutoyo. If you don’t have a micrometer screw gauge yet then you could do a lot worse at this end of the market.
The countdown for the first step on humanity’s return to the Moon has begun. The countdown for Artemis 1 started on Saturday morning, and if all goes well, the un-crewed Orion spacecraft atop the giant Space Launch Systems (SLS) booster will liftoff from the storied Pad 39B at Cape Canaveral on Monday, August 29, at 8:33 AM EDT (1233 GMT). The mission is slated to last for about 42 days, which seems longish considering the longest manned Apollo missions only lasted around 12 days. But, without the constraint of storing enough consumables for a crew, Artemis is free to take the scenic route to the Moon, as it were. No matter what your position is on manned space exploration, it’s hard to deny that launching a rocket as big as the SLS is something to get excited about. After all, it’s been 50 years since anything remotely as powerful as the SLS has headed to space, and it’s an event that’s expected to draw 100,000 people to watch it in person. We’ll have to stick to the NASA live stream ourselves; having seen a Space Shuttle launch in person in 1990, we can’t express how much we envy anyone who gets to experience this launch up close. Continue reading “Hackaday Links: August 28, 2022”→
My wife and I are reading a book about physics in the early 1900s. It’s half history of science and half biography of some of the most famous physicists, and it’s good fun. But it got me thinking about the state of physics 120 years ago.
What we’d now call classical mechanics was fully settled for quite a while, and even the mysterious electricity and magnetism had been recently put to rest by Maxwell and Heaviside. It seemed like there was nothing left to explain for a while. And then all the doors broke wide open.
As much as I personally like Einstein’s relativity work, I’d say the most revolutionary change in perspective, and driver of the most research in the intervening century, was quantum mechanics. And how did it all start? In the strangest of ways – with Niels Bohr worrying about why hydrogen and helium gasses gave off particular colors when ionized, which lead to his model of the atom and the idea of energy in quantum packets. Or maybe it was De Broglie’s idea that electrons could behave like waves or magnets, from slit and cathode-ray experiments respectively, that lead to Heisenberg’s uncertainty principle.
Either way, the birth of the strangest and most profound physics revolution – quantum mechanics – came from answering some ridiculously simple and straightforward questions. Why does helium emit pink, and how do TVs work? (I know, they didn’t have TVs yet…) Nobody looking at these phenomena, apart or together, could have thought that answering them would have required a complete re-thinking of how we think about reality. And yet it did.
I can’t help but wonder if there are, in addition to the multi-bazillion dollar projects like the Large Hadron Collider or the James Webb Space Telescope, some simpler phenomena out there that we should be asking “why?” about. Are we in a similar quiet before the storm? Or is it really true that the way to keep pushing back the boundaries of our ignorance is through these mega-projects?
This article is part of the Hackaday.com newsletter, delivered every seven days for each of the last 200+ weeks. It also includes our favorite articles from the last seven days that you can see on the web version of the newsletter.
Want this type of article to hit your inbox every Friday morning? You should sign up!
This week, Editor-in-Chief Elliot Williams and Assignments Editor Kristina Panos met up on a secret server to discuss the cream of this week’s crop of hacks. After gushing about the first-ever Kansas City Keyboard Meetup coming up tomorrow — Saturday the 27th, we start off by considering the considerable engineering challenge of building a knife-throwing machine, the logistics of live-streaming on the go, and the thermodynamics of split-level homes.
This week, Kristina came up with the What’s-That-Sound and managed to stump Elliot for a while, though he did eventually guess correctly after the tape stopped rolling. Think you know what it is? Then fill out the form and you’ll earn the chance to win a genuine Hackaday Podcast t-shirt!
Later in the show, we look at a macro pad that breaks the mold, an ASCII terminal like it’s 1974, and a Z80 that never was (but definitely could have been). Stick around as we root for the CubeSats hitching a ride aboard Artemis I, and at last call on the ‘cast, it’s lagers vs. ales (vs. ciders).
