Fill your bowl with an all-you-can-eat continental breakfast of all things RISC OS at the Big Ben Club’s annual day.
The show is on the 9th May from 10am to 4pm and is located in Koog aan de Zaan. It’s easy to reach being only a short distance north of Amsterdam by car, public transport, or even by bicycle.
Visitors can also use the shared tables to show off their own setups to one another.
A computer terminal based on the Rockwell 6511Q microprocessor. All scans, ROM dumps and circuit diagram thanks to Robert Offner! c’T 1983 Heft 12, 1984 Heft 1 See also:KIM-1 connectors: beware the Chinese cheap variants!The KIM-1 needs 2 edge connectors. The specifications are: card edge; PIN: 44; 3.96mm When you search for those, ...Magazines: Compute! […]
Vintagetech (Dave Williams) has scanned and dumped more MTU material in 2026: MTU K-1008 Visable Memory KIM-1 Introduction MTU Catalog October 1978 A1 INSMUS-8 INSNOTRAN Music compiler Datamover-256 Hardware Manual 1982-06 Rev A MTU-130 MACASM Release 1.2 User Manual 1982-10 Preliminary KGP Doc MTU K-1032 Banker RAM ROM manual Rev E Optional Software (added May […]
Testing MacOS on the Apple Network Server 2.0 ROMs
(date: 2026-05-03, updated: 2026-05-06)
It's time for another save point in the continuing saga of the various ROMs for the Apple Network Server, Apple's first through-and-through Unix server ( previously, previously). The Apple Network Server was only ever officially able to boot AIX, IBM's proprietary Power ISA-specific Unix, though it was originally intended to run Novell NetWare and was demonstrated booting Mac OS with early pre-production ROMs. However, much to industry surprise, late in its life cycle then-CTO Ellen Hancock announced that the ANS would be able to boot Mac OS and even Windows NT as well using ROM upgrades. Neither ROM was officially released before Steve Jobs convinced Gil Amelio to cancel the line, and for many years they were believed to be vapourware.
But they've started to surface, first with an ex-Apple employee who had both the preproduction ROM and the Mac OS ROM on a flash ROM SIMM, and later another employee turned up with the NT ROM, though sadly more is needed to make it actually run NT. It turned out that I also had the preproduction ROM in a box gathering dust, and a couple months ago we put both the preproduction ROMs and NT ROMs through their paces.
Well, thanks to Jeff Walther who generously built a few replica ROM SIMMs for me to test, we can now try the "2.0" MacOS ROMs on holmstock, our hard-working Apple Network Server 700 test rig ( stockholm, my original ANS 500, is still officially a production unit). And there are some interesting things to report, especially when we pit the preproduction ROMs and this set head-to-head in MacBench, and even try booting Rhapsody on it.
When we last left the 700, it still had the preproduction 1.1.20.1 ROM installed, which can be used to boot either MacOS or AIX and makes it look to MacOS like a Power Macintosh 9500, the ANS's closest relative. However, the ANS has unique hardware: two Symbios Logic 53C825A SCSI-2 Fast and Wide controllers (20MB/s) for the internal SCSI bays and on-board Cirrus Logic 54M30 graphics used in no other Apple product. MacOS never supported these and the preproduction ROM does not contain support for them, so to boot Mac OS you have to use the external 5MB/s CURIO SCSI (the ANS doesn't have the typical Power Macintosh MESH controller) and a Mac-compatible PCI video card. I selected a IMS TwinTurbo, the same card shipped with the Power Macintosh 9500, and booted it off an external BlueSCSI, both of which work well for this purpose. Once you get everything set up, versions up to at least Mac OS 9.1 are compatible, though with various annoying glitches you have to work around because it's not really a 9500.
The value proposition of the 2.0 ROM is that support for Cirrus video and 53C825A SCSI comes standard — the drivers are built-in to the firmware. You can then boot Mac OS from the internal CD and install it to an internal SCSI disk at full speed, and connect your monitor directly to the ANS's VGA port (one of the only Apple systems of this era to have a standard HDI-15 video connector instead of the usual Mac DA-15). To test this, we'll unplug the BlueSCSI, remove the TwinTurbo and also take out the ANS-specific 10Mbit Ethernet card I installed because the onboard MACE Ethernet wasn't working, just in case it makes a difference. (More on that in a bit.)
The ANS also has a front-mounted LCD which can be used for displaying system status or other notifications. AIX and NetBSD both directly support it. Ordinarily this would be full of diagnostics and POST messages while the system boots, but the LCD is completely blank with the 2.0 ROMs installed and never shows any activity. In fact, it's the same kind of blank you'd get if the processor board went wacky, which is a little unnerving to an old ANS hand like me.
For some reason, and it could be my system because I usually have the PRAM battery out to let the logic board more quickly reset between experiments, I always had to three-finger reset it with Control-Command-Reset to get it to bong. The bong this ROM makes also seems a little truncated, and compared to regular ROMs with the extensive Long RAM test, these ROMs come up very quickly to the patterned Toolbox background. We have nothing installed it can boot from, so it almost immediately displays a gimme-disk animation, just like a regular Mac. But unlike most other Old World Macs (and the preproduction ROMs), the icon is in colour, because this is Open Firmware 2.0.
I reset it again and held down Command-Option-O-F to force Open Firmware to start. This also comes up immediately, and on the main screen as it would on a regular ANS.
This ROM is notable in that, besides the usual bye and boot words, there is an io word to redirect output for you. If you type ttya io at the console, it immediately switches to serial on rear port 2 at 38400bps by default. We want to see if it does anything interesting when we start it, so we'll setenv input-device ttya:57600, setenv output-device ttya:57600 and reset-all to default it to serial startup, but we still have to hold down Cmd-Opt-O-F or it snaps back into the Toolbox ROM. Let's dump the device tree.
This is a little different from the device trees on our other ROMs, and not everything seems to work or was updated, suggesting this was unfinished at the time the product was cancelled. For example, if we look at the list of device aliases ...
... the definition for the internal SCSI doesn't actually exist. You'd think that scsi-int would point to the internal SCSI, and a path like /bandit/gc/mesh (GC in this case is Grand Central) would do so on a regular Power Mac, but the ANS doesn't have a MESH. That means trying to list the contents of a CD-ROM in the internal optical drive, ordinarily SCSI 0 on an ANS ...
ok
0 > dir scsi-int/sd@0,0:,\ unable to open the DIR device
Also, even though there is an AIX loader package in the 2.0 ROMs, it doesn't work either (using a bootable 4.1.5 CD):
ok
0 > boot /bandit/apple53C8xx@11/sd@0,0:aix loader: unrecognized client program format
state not valid
In fact, if you have a bootable AIX drive plugged in, the system will crash. I found that out when the ANS was freezing up shortly after POST and I eventually tracked down the culprit.
By comparison, the 1.1.20 preproduction ROMs show a much more sensible list of device aliases.
Accordingly, a command like boot disk0:aix or boot /bandit/53c825@11/sd@0,0:aix will boot AIX from the internal CD-ROM.
The Network Server Diagnostic Utility (NSDU) shows other strange stuff. Because it never runs a Long RAM test, the RAM is never marked parity (even though it is; we labouriously dug out every parity FPM DIMM we had in stock to put in this thing). On ANS production ROMs (and the preproduction ROMs), the ROM will set the RAM timing to 70ns instead of 60ns if any stick of RAM is not parity, a rare case of where having parity memory improves performance. It's not clear what this ROM does in that instance, and in any case there are bigger problems such as the absolutely preposterous processor speed (this is a 150MHz PowerPC 604e). The L2 cache, at least, is correctly detected as the standard 700 1MB. We'll come back to this too.
For comparison, here's what a proper diagnostics readout would look like with the preproduction ROMs (slots 1 and 6 contain our video and Ethernet cards).
Well, let's try to start it up. I got out a retail Mac OS 9.1 CD and put it into the internal CD-ROM, with no other drives installed.
The system immediately booted. Again, the Happy Mac is colour, because this is a later Open Firmware.
Starting up. There is nothing connected to the external SCSI port — it's booting entirely on the fast internal SCSI — and the video is coming from the logic board. It all "just worked."
And it gets to the desktop just fine. Still, it seemed a little poky and I didn't remember it being quite that bad with the preproduction firmware. It wasn't clear to me if this was the video hardware or something more intrinsic to the system, so we should really set up an OS install and do a proper benchmark.
To put the internal SCSI through its paces requires hardware capable of keeping up with it, so I got out a newer ZuluSCSI Wide, installed it in a drive tray with a 68-pin SCSI mezz interposer, created a 4GB blank disk image and ran a clean Mac OS 9.1 installation. To my surprise, on rebooting I was able to plug in an AAUI dongle to the internal MACE Ethernet and it worked just fine when it wasn't working before, so I then added TattleTech, Gauge PRO and MacBench 5.0 from the home AppleShare server. Since I figured I'd want to compare this to the preproduction ROMs, rather than find an external CD-ROM I also used Disk Copy 6.5b11 to make an image of the MacBench CD for the graphics tests. We'll then use the same disk image in the external BlueSCSI for consistency.
As before, the Gestalt ID (as reported in both Apple System Profiler and TattleTech) is the same as the Power Macintosh 9500 and Workgroup Server 9650. However, the ROM version is $772.7DD0. To the best of my knowledge, this is unique to this ROM.
Apple System Profiler was taking an inordinately long amount of time to update the screen and I knew it hadn't been that bad. It also reported a bogus amount of L2 cache (2MB) despite the figure in the NSDU. But both Gauge PRO and TattleTech said there was no cache.
Also as the NSDU had reported, the RAM was not seen as parity and parity checking was disabled.
The Shiner-specific hardware is all correctly enumerated by Apple System Profiler. Both SCSI controllers appear and would have their own bus. In this case we're only using one bus, but there could potentially be three if you had a whole lot of drives installed and were using the external SCSI as well. They appear as PCI devices hanging off the on-board Bandit PCI controllers.
The Cirrus Logic 54M30 also appears, but its maximum colour depth is still limited to 8-bit (256 colours) like it is in AIX, even though there is more than enough VRAM to support a higher colour depth. The reason is, according to the Network Server Hardware Developer's Notes, "This controller implements only a little-endian window into the packed-pixel frame buffer, hence Big Endian operating systems are limited to 8 bits per pixel unless low-level transformation routines are written." [sic] It looks like that wasn't done here either.
The Ethernet is shown coming from "Built-In," off the on-board MACE, and our AppleShare server is connected from it. Nice to see that the logic board wasn't at fault after all.
Our ZuluSCSI Wide that we booted from is also rated for the full 20MB/s. It should run like a bat out of hell.
And the problem is ... this system doesn't. Even considering the reference comparison for this version of MacBench 5.0 is a 300MHz Power Macintosh G3, the 2.0 ROM's performance in Mac OS is absolutely dismal. Graphics, CPU and FPU testing are all between three and five times slower than the G3 reference. Although the disk performance seems superficially decent at sixty percent of the G3's, with the fast SD card in the ZuluSCSI and the full 20MB/s available we should have done a lot better.
I tried to make it a fair fight by putting in the TwinTurbo video card again, since we'll need it to run the tests on the preproduction ROMs. I used 24-bit colour depth since that would be the major advantage of using it. (Interestingly, when you start the system this way, there is a pause at the beginning where you see what looks like an Open Firmware cursor, then some garbage, then the Toolbox pattern.)
Even with its hands tied behind its back, as it were, the TwinTurbo still managed 20 percent of the G3 reference despite pushing three times the pixel data as the on-board Cirrus. That doesn't speak well of the Cirrus video's performance, or at least of the ROM driver for it.
At this point I had to know if I was imagining things, so I yanked the 2.0 ROMs, put back in my 1.1.20 ROMs, copied the disk image to the BlueSCSI and booted from the external SCSI port. The Ethernet immediately stopped working, using the same AAUI dongle, same Ethernet cable and same port, so it looks like these ROMs don't support the on-board Ethernet after all and I had to put the ANS 10Mbit Tulip Ethernet card back in. But hey, it's not the board!
The $77D.28F2 version for this ROM as reported by Apple System Profiler is the same as the 9500 and related systems. Although TattleTech still doesn't see the L2 cache, Gauge PRO does, and both Apple System Profiler and Gauge PRO agree on the correct size (1MB).
On the other hand, TattleTech does not report the RAM as being parity, despite a successful Long RAM test. We'll go with the NSDU's assessment here. I'm also not sure what to make of the lower "moving memory" rating, so let's run everything through MacBench again.
It's not even close, folks. CPU was 35% of the reference G3 (a whopping 75% faster), FPU 47% (47% faster), and graphics 33% at millions of colours (65% faster). But the real shame is the disk score: despite being on an interface up to four times slower, the preproduction ROMs get eighty-nine percent of the reference G3 — 48% faster!
My suspicion is this can be chalked up largely to the complete fail on the L2 cache and possibly also to the RAM speed, but either way, it was shocking how badly the 2.0 ROMs performed.
Still, if the 2.0 ROM can boot other operating systems, that might redeem it for certain purposes. We already had a fully installed Rhapsody 5.6 (essentially pre-Mac OS X NeXTSTEP ported to PowerPC and sold as Mac OS X Server v1.2) image on a BlueSCSI we tried to boot without success on the preproduction ROMs, so let's try that here — if Rhapsody works, we might get Mac OS X working next.
The magic boot string from the BlueSCSI on the external port, for a disk image set to device 2, turned out to be boot scsi/sd@2,0:0 scsi/sd@2,0:8,mach_kernel (using a "partition zero" loader to chain into the actual Rhapsody kernel). On the preproduction ROMs, we got a CLAIM failed from Open Firmware no matter what settings I tried.
On the 2.0 ROMs, it started immediately, though on the internal video it just made some colourful displays. On the TwinTurbo I actually got a proper startup screen, and I thought we were getting somewhere until I abruptly got this kernel panic. (What a pretty icon for a kernel panic window!) The problem seems to be that waitForInterrupt bombed out, possibly because of the different interrupt setup on the ANS compared to the 9500.
I tried a verbose boot (hold down V as you're entering that boot command) to see if I could get more information. It seemed to be loading drivers just fine from the Rhapsody partition ...
... but it still crashed in the same way, though we can see from the bigger window this time that much of the system is correctly detected.
Just for yuks I tried Rhapsody Developer Release 2 instead. The Mac OS-side installer will run, but I couldn't get it into the second installer stage despite poking around on partition 10 where it claimed to want to boot from. I also tried booting from the Mac OS X 10.0.3 and 10.2 CDs, but while I got a Happy Mac, the system simply locked up after.
So after all that, if you want to run Mac OS with top performance on the Apple Network Server, you need to be running the preproduction ROMs — not the 2.0 ROMs. I don't think the 2.0 ROMs were ever actually finished, or at least not these 2.0 ROMs, or more elemental issues like the L2 cache support would have gotten fixed. It certainly does smooth out certain rough spots, it supports all the ANS hardware as advertised, and it was more reliable with reboots, but the speed penalty you'll take running it just doesn't seem worth it. I could only see myself running this version if I had to have the biggest, baddest, meanest AppleShare server with tons of SCSI drives in Mac OS. Is there a later version out there yet to be found that does deal with those problems?
Meanwhile, I'm going to work on a patched version of Mac OS for this machine to fix the reboot problems in 1.1.20, which I believe should be solveable with some resource hacking. That said, I'm not done with these ROMs just yet: I think Rhapsody, at least, can be made to work but it clearly needs a kernel patch, and I suspect the former Apple employee who got it working on the 2.0 ROMs did just that. Performance might still be hideously bad, but it's nevertheless another solid Un*xy option for Apple's best beige Unix box, and it even has historical value. To be continued if I can get my hands on some Rhapsody source code. Anybody feel leaky? Post in the comments or drop me a line (no worries keeping you anonymous) at ckaiser at floodgap dawt com.
The Mystery of Rennes-le-Château, Part 5: The Man Behind the Curtain
(date: 2026-05-01, updated: 2026-05-02)
This series of articles chronicles the history, both real and pseudo, behind Gabriel Knight 3: Blood of the Sacred, Blood of the Damned. It is possible to trace the Plantard family tree a fair ways back without relying on the Lobineau dossier, but not as far back as the time when the Merovingian kings ruled […]
There are a lot of Commodore 64s out there. We are blessed with an abundance of options. There are the motherboard reproductions that you can populate with original chips, like the C64 Reloaded. There are reimagined mainboards that take original chips, like Uni64. There are advanced FPGA mainboards like the Ultimate64. There are oddball standalone FPGA implementations, like TurboChameleon64. There are whole package reproductions, like the Commodore 64 Ultimate and the Mega65. There are Raspberry Pi-based solutions, like the BareMetalC64, which runs VICE. And there other dedicated VICE solutions, like THEC64 mini, and even THEC64 Maxi with the full sized working keyboard. There are a lot of solutions to get your C64 fix. It's kinda mind blowing, when you think about it. I'm probably missing a few options too. But almost all of these are designed for the desktop or the living room. That's great, but it has its limitations. Retro Games Ltd., the creators of THEC64 mini and Maxi, are intro. . .
Eduardo Casino has done a great job replicating the PCB of the Jolt. And he proved the PCB was OK by building a Jolt and setting it to work. I have populated a replica PCB with as much as I have in my junk boxes ‘time period correct’ parts. It does look good compared to […]
The King is in his counting house – in Silver River Kingdom
(date: 2026-04-26)
Initially released at the RISC OS North show last month, the latest title from AMCOG Games has now been made more widely available. Silver River Kingdom can now be purchased via !Store, priced at £14.99. Anyone who purchased the game at the show can – and should, to ensure they have the most up to date version – download the game free of charge from !Store, by using the download code found in the packaging; just input the code in the “Special instructions, promo code, etc.” field in the application.…
b.log 2026/04/25 - Pineapple does NOT belong on pizza, Stapler!, The fake 1MHz bus, The 6821 PIA - the fly in the ointment, Rogue state, Beads, Be nice to the fairies.
(date: 2026-04-25, updated: 2026-05-04)
Pineapple does NOT belong on pizza, Stapler!, The fake 1MHz bus, The 6821 PIA - the fly in the ointment, Rogue state, Beads, Be nice to the fairies.
R65 – A late seventies computer built with a KIM-1
(date: 2026-04-24, updated: 2026-05-05)
R65 – A late seventies computer built with a KIM-1 by Rene Richarz. An amazing showcase of how far a KIM-1 and Pascal as programming language can go! All information on the R65 and the emulator of this computer on the github archive of Rene Richarz, a work in progress! Including sources and full documentation. […]
There is another developer chat is on saturday night (25th April) for anyone interested in a very informal event online aimed at RISC OS developers of all levels.
The next online meeting for anyone who is interested in the topic of developing on or for RISC OS will take place online on Saturday, 25th April. As ever, these friendly fireside chats are an informal way for developers and those with a passing interest to get together and discuss the issues that affect them or they feel are relevant. There is no set agenda, so the areas covered by the meeting are steered by those present – meaning you can bring up a burning issue, pose a problem to…
Image: The handcart, equipped with a sail. Photo by Kris De Decker.
The human-powered handcart is the oldest of vehicles, and it will likely be the last one around in the future. Of all vehicles, it’s the cheapest and least complex to build and use. It offers a large advantage over carrying a load on your back or dragging it over the ground - the even older concept of the sled. On the other hand, the handcart is cheaper and easier to use than the animal-powered cart. Oxen and donkeys eat more than humans, and they have their own will, which can work against the driver.
Like any other wheeled vehicle, the handcart requires roads to drive on. This infrastructure has not always been available anywhere or at any time in history. For example, in medieval Europe, porters and pack animals were more common than handcarts because of poor roads. 1 In the West, the handcart only reached its heyday during the first decades of the Industrial Revolution, when it connected fast-growing cities to train stations and harbors. In China, on the other hand, the handcart was the backbone of the transport network for millennia. 2
Of all vehicles, the handcart is the cheapest and least complex to build and use.
There are still many human-powered carts in modern society: strollers, grocery carts, roller suitcases, and various utility and folding carts. However, these modern carts are to their predecessors what birds are to dinosaurs. They are small, often with very small wheels, and we use them for very short distances, usually inside buildings. In contrast, old-fashioned handcarts were often large and had big wheels, and they were pushed or pulled on roads and over longer distances. Many crafts and professions had their own type of handcart.
Image: Low-tech Magazine's handcart. Photo by Kris De Decker.
Why I need a handcart
People still use large handcarts in so-called “developing countries”. However, they can be just as useful again in the large cities of the industrialized world, as I can testify after using one for a couple of months. Last autumn, I received an internship application from Kozimo, who studies at the Design Academy Eindhoven. In his application, Kozimo sent a video of a large handcart he made, which he was driving on the streets of Rotterdam, the Netherlands.
I have always dreamt of a handcart. I have never owned a car, and the only times I miss one are when I have to move stuff, something which has become increasingly common lately. Consequently, I proposed to Kozimo to build a handcart for me.
Now, I can no longer imagine living without it. I have used the vehicle to move houses and offices, pick up materials and objects I bought online, new or second-hand, and transport workshop and event materials (bike generators, solar panels, solar ovens, books, sound systems). I have done the same for friends. During these trips, I often took home materials, furniture, or objects that I found for free on the streets of Barcelona.
Image: Kozimo and Kris De Decker with Low-tech Magazine's handcart, halfway through a 30 km trip along the coast of Spain. Photo by Linda Osusky.
Unlike a van or a car, my handcart doesn’t need gasoline, electricity, or batteries, making it entirely independent from energy infrastructures. Neither do I need to pay taxes and insurance. The handcart is a very democratic vehicle. It allows anyone to carry a load wherever they want, while older, less affordable cars and vans are no longer allowed to enter city centers due to the installation of Low Emission Zones.
A handcart doesn’t need gasoline, electricity, or batteries, making it entirely independent from energy infrastructures.
It would make a lot of sense to offer vehicles like this at community centers, where they are available for all neighbors to use when needed. Few people would need a handcart each day, and communal use would solve the parking problem. Although our handcart can also be parked vertically, it won’t fit in most apartments.
Description of the handcart
This article will not explain in detail how to build a handcart. We want to do that another time with a simpler handcart model, because the vehicle we present in this article is not one that most people can make themselves. You need good woodworking and metalworking skills, and in fact, two people made the handcart.
Kozimo designed and built the whole structure from wood, while Guilhem Senges - visual artist and one of my neighbors - designed and made several essential reinforcements from metal; the wheels, the brakes, and the handlebars are all connected to the wood structure with custom-made iron parts.
Image: The underside of the handcart. Photo by Kris De Decker.
Images: The front and back of the handcart. Photos by Kris De Decker.
Image: The lights are mounted in coconuts. Photo by Kris De Decker.
Load weight and volume
Low-tech Magazine’s handcart is 250 cm long and 100 cm wide, while the platform itself measures 210 by 85 cm. Assuming a load height of 50 cm, the cargo volume is roughly 1.55 m3 (37 cubic feet or 1050 liters). That’s two to four times the typical trunk space in a European car. We have transported cargo that is wider or longer than the cart: a large heated table measuring 140x140cm, and several loads of wooden beams, each three meters long.
The load weight is limited by the wheels, which come from a wheelchair. They can support up to 150 kg. 3 The cart itself weighs 32 kg, so the practical maximum cargo weight is about 120 kg. The loading platform consists of slats with gaps between them, making it easy to secure various types of cargo.
Images: The handcart with various cargoes. Upper left: a 6m2 wooden floor and a chest. Upper right: 3-meter-long wood beams. Below: A heated table ready for transport.
It drives itself!
Over the past few months, we’ve learned that people have many misconceptions about handcarts. For example, you may think that pushing a handcart takes a lot of effort, perhaps based on your experience pushing supermarket carts through parking lots or pulling heavy suitcases through city centers (which is how I moved stuff before I had a handcart).
However, using the handcart can be so effortless - even when it’s heavily loaded - that it feels like you are not pushing at all. Once in motion, you can often guide it with one hand, and it sometimes feels like the cart is pulling you forward. It’s no exaggeration to say that pushing the handcart with a 100 kg load is more comfortable than walking while carrying a 10 kg heavy backpack.
Using the handcart can be so effortless - even when it’s heavily loaded - that it feels like you are not pushing at all.
There are several reasons for this light operation, rooted in physics. Each vehicle has to overcome three forces: rolling resistance, air resistance, and gravity. Air resistance is negligible at walking speed, meaning that a handcart user on flat terrain mainly needs to overcome rolling resistance. That’s the friction between wheels and road surface, a factor that’s largely independent of speed.
In contrast, air resistance increases with the square of speed. A cyclist, going at 15-20 km/h, already spends more effort overcoming air resistance than overcoming rolling resistance, which is the same in both cases because both vehicles have similar wheels. In short, the handcart’s low speed minimizes air resistance, while its narrow wheels minimize rolling resistance.
Image: Driving the handcart. Photo by Linda Osusky.
Second, accelerating a vehicle requires more energy than maintaining a constant speed. You only need to sustain momentum, not build it. Our handcart is pushed by a person walking, so the effort to accelerate lasts no longer than one or two seconds. In contrast, a cyclist takes much longer to reach cruise speed, and because of the higher air resistance, it takes more effort to sustain that speed. If the handcart is heavily loaded, it also gains significant kinetic energy, even at low speed. That explains why it sometimes feels like the cart is pulling you forward - because it actually is.
Finally, our wheels are much larger than those used on modern pushcarts. That makes for comfortable driving on asphalt and sidewalks, which are not as smooth as airport or supermarket floors. Large wheels increase air resistance, but because of our low speed, that doesn’t matter.
Handcarts and gravity
However, an effortless ride requires two conditions: flat terrain and a well-balanced load. Both involve the third force any vehicle must overcome: gravity.
Balancing the handcart: distributing the load
A two-wheeled cart becomes heavy and difficult to use when too much weight is placed on the front or back. Consequently, you need to load the vehicle so that the weight is equal on both sides of the wheels. That’s easy to check: the cart should remain in a horizontal position for several seconds without you touching it. If there’s just one piece of cargo, place it above the center of the wheels. If there are more things to carry, the total weight should be divided equally over the two sides. Finetuning the balance often involves moving a backpack from the front to the back of the cart, or vice versa.
You need to load the vehicle so that the weight is equal on both sides of the wheels.
A two-wheeled cart also needs additional support to keep it horizontal when parked, for instance, when loading or unloading cargo. Otherwise, the cart may suddenly flip to the other side. Our handcart carries four support beams, two on each side. When the cart is moving, they are in a horizontal position. When the cart is parked, we remove one or more beams and place them in a vertical position. Each beam can be set to a different length, allowing us to stabilize the cart on uneven terrain. We tighten the beams with screws.
Image: The handcart is parked with four supporting legs. Photo by Kris De Decker.
Image: Detail of the supporting beam holder. Photo by Kris De Decker.
Many people have asked us why we didn’t build a four-wheeled cart that wouldn’t need to be balanced. However, four wheels would double the rolling resistance and thus the effort required to push the cart. Furthermore, a four-wheeled cart is less maneuverable and more difficult to drive on uneven terrain. You also need to get two extra wheels, and you need to build a steering mechanism. Throughout history, the two-wheeled handcart (or one-wheeled handcart in the case of China) was much more common than the four-wheeled cart. 1
Going uphill: you need help
An effortless ride also requires more or less flat terrain, which is what you get here in many parts of Barcelona. If you go up a steep slope, you suddenly feel the weight of the cart and its cargo. Climbing with a heavily loaded cart can be as strenuous as running up stairs or cycling at top speed. People tell us we should put an electric motor on the cart, and that’s perfectly possible.
However, we found a simpler solution: if necessary, we ask for help from another person. Our handlebars are wide enough for two or even three people to push together, which makes going uphill a lot easier. Adding an electric motor and a battery would significantly increase the vehicle’s weight, and it only makes sense if you regularly have to climb hills.
Going downhill: brakes
Going downhill, you have to counter gravity forces to prevent the handcart from hurling down a slope, which would be very dangerous. Rather than pushing the cart, you’ll have to pull it back instead. Here, cyclists have all the advantage, as they can use gravity to its full benefit during a descent.
We made going downhill a lot easier by adding bicycle brakes. In combination with the large wheels, the brakes also allow the handcart to be taken down sidewalk curbs or even stairs without damaging it. They double as a hand brake as well, by tightening two lashing straps around them. That allows leaving the cart unattended on a slope or in high winds.
Image: The brakes. Photo by Kris De Decker.
Handcarts go on the sidewalk
Many people assume that handcarts go on the road, with the cars, or on the cycling path. That’s not the case: you use it on the sidewalk. Legally, handcart users are in a similar position to other pedestrians pushing a smaller handcart, such as a stroller. The only difference is that, when they are forced onto the road because there’s no sidewalk or it’s blocked, handcart users should walk on the right side of the road, while other pedestrians should walk on the left. For now, the police have stopped us only once, and they were just curious.
Legally, handcart users are in a similar position to other pedestrians pushing a smaller handcart, such as a stroller.
We could find no traffic laws that limit the size of a handcart, at least not in the handful of countries we researched, including Spain. However, in practice, there are clear limits. If your vehicle is wider than the space between traffic bollards that keep cars out of pedestrian streets, all pedestrian zones will become inaccessible to you. You should also take into account other obstacles on the sidewalk, such as building scaffolding. Consequently, it’s rarely practical to build a handcart more than one meter wide.
Barcelona has very wide sidewalks in most of the city. We rarely have to share the road with cars or cyclists. Of course, that’s not the case in every city, and then the use of a handcart becomes less attractive. Using a handcart on the road or cyclepath is rather dangerous because other vehicles are much faster.
Image: Kozimo pushes the handcart through a narrow walkway. Photo by Kris De Decker.
Respecting other pedestrians
Driving a large handcart on the sidewalk demands your full attention. You don’t want to hit any infrastructure, and you surely don’t want to hit someone’s legs. You need to drive it with respect for other pedestrians and their pets (some dogs start barking at the vehicle). In general, the handcart is very safe to use because it travels at a very low speed. That makes accidents less likely in the first place and less impactful if they do happen. You also have a very good overview of your vehicle, much better than for a car or a bicycle. As long as you keep your eyes on the handcart, you are unlikely to hit anything or anyone.
However, our handcart is so silent that people don’t hear it coming. We added a bicycle bell to warn people, but we hope to find a better tune in the future: every vehicle needs its own type of sound. We also need a bell for oncoming pedestrians who are watching their phones while walking and expect others to make space. With the handcart, we cannot always make that space. Our handcart has front and rear lights as well, wired to a USB power bank mounted underneath the platform. Lights are very helpful on sidewalks, both day and night, as they make the vehicle more visible. Furthermore, lights are essential if you need to move onto the road after dark.
Images: Kris De Decker drives the handcart through Barcelona. Photos by Guillaume Lion.
Even in Barcelona, sidewalks can get crowded, and a busy sidewalk will slow down the vehicle considerably. With little chance to overtake someone, we tend to get stuck behind the slowest walkers.
A handcart is not a difficult vehicle to drive, but nowadays people in industrialized societies have no experience with it. Apart from driving it attentively, you also need to be careful when rounding blind corners (take the turn as wide as possible) and when you leave a garage or any other type of exit (pull rather than push the cart). By the time you see oncoming traffic, you already have 2 meters of your handcart on the road or around the corner.
Why not a bike trailer?
Almost everyone who sees the handcart for the first time asks the same question: how do you attach it to a bicycle? You don’t. You push it while walking. When we say that, there follows a silence. Pushing a handcart seems like one step too far back, even for people committed to living more sustainably. Why would you push a handcart if you could just as well use a much faster bike trailer, or a cargo bike?
In fact, there are several practical reasons to opt for a handcart rather than a bike trailer, and we have already mentioned many of them. First, a handcart lets you go anywhere a pedestrian can, while cyclists often need to get off their bikes and push them - just like a handcart. A handcart is also more agile. For example, although the cart is 2.5 meters long, it takes just two seconds and little space to turn it around and walk in the opposite direction from where you came from.
Why would you push a handcart if you could just as well use a much faster bike trailer, or a cargo bike?
A handcart can be built larger than a bike trailer as well. Although it’s perfectly possible to build a bike trailer the size of our handcart, its higher speed would pose much greater risk of accidents and damage, both to the cart and to other road users. As a bike trailer, it would also need to be made sturdier, and it would need a more elaborate mechanism to operate the brakes.
All this does not mean that bike trailers are a bad idea. We have used the handcart mainly for trips between 5 and 10 km, which comes down to one to two hours of walking. For longer distances, the bike trailer has the obvious advantage of speed. If you need to cover 40 km, you would need to travel eight hours with a handcart, compared to just two hours with a bike trailer.
Image: Guilhem Senges, who built the vehicle's metal parts, pushes the handcart to a welding job a few streets up in the neighborhood.
The merits of slow travel
However, when people ask us why we don’t use it as a bike trailer, we can also answer differently: why the rush? Deciding to travel with the slowest vehicle possible is subversive because it questions values we take for granted in the modern world, such as speed and utility.
To many people, walking a handcart seems like a waste of time, but our experience is exactly the opposite. Every trip is an adventure, and we always look forward to using it again. It’s a pleasure to drive the vehicle, more like steering a boat than driving a land vehicle. It’s easy to chat with other pedestrians, who tend to be very curious about our vehicle. Consequently, the trip takes even longer.
To many people, walking a handcart seems like a waste of time, but our experience is exactly the opposite.
Driving a handcart feels entirely different from using any other mode of transport. When people are walking, they usually cannot carry much with them, either in terms of weight or volume. In contrast, the handcart allows you to walk with a lot of stuff close at hand: drinks, food, a sound system, books, extra clothes. Furthermore, you have a large platform, which allows you to rest and invite others to do the same. It becomes a vehicle for wandering and roaming, and for connecting to other people.
Image: It's a pleasure to drive the vehicle, more like steering a boat than driving a land vehicle. Model: Rocío Sánchez. Photo by Kris De Decker.
Image: The handcart with rain protection. Photo by Kris De Decker.
Handcart Accessories
Once the handcart proved its utility as a cargo vehicle, Kozimo began designing and building additional structures to expand its uses. These objects make use of the slatted platform or the support beam design. Unfortunately, Kozimo’s internship ended before we could test all these extensions, but the little experience we gained by now shows that the handcart can be much more than just a cargo vehicle.
Passenger seat
The first, and perhaps most powerful addition, is a foldable seat. While our handcart can be - and usually is - operated by only one person, it’s ideally handled by two people, especially for longer voyages. Thanks to the seat, one person can push the cart while the other one rests in the vehicle.
As long as the road is flat, the extra weight of the passenger does not significantly increase the effort to push the cart. Consequently, two people can travel faster or farther in a single day. When climbing hills or bridges, the passenger gets off the seat. If necessary, he or she also helps to push the cart.
One person can push the cart while the other one rests in the vehicle, increasing the distance that two people can travel in a day.
An extra pair of eyes on the road is also handy. The seat can be put in two positions, so that both the passenger and the driver are either looking in the same direction or facing each other, which makes it easier to talk and allows the passenger to serve as the rear-view mirror.
We used the seat on a 30 km day trip along the coast of Catalunya, Spain, moving stuff from my old place to my new place. For one person, this would have been an exhausting trip. However, there were several people on the way there, and two people on the way back. The fact that we could rest from time to time - without stopping - made a great difference, especially on the way back. An extra person also proved useful when unexpected obstacles arose. For example, there was a bridge under repair, which forced us to carry the cart down the rocks, over the beach, and up the rocks again.
Image: A foldable seat on the slatted platform. Photo by Kris De Decker.
Image: Kozimo drives the handcart along the coast. Linda Osusky is filming while resting in the seat. Photo by Kris De Decker.
Images: Carrying the handcart over the rocks. Photos by Linda Osusky.
Digital nomad office
As a second addition, we combined the seat with a work table that doubles as a solar power plant, resulting in a digital nomad office. The table fits onto the sides of the handcart and slides back and forth. The solar panel can be in a horizontal position or at various tilted angles. It can charge a laptop or any other device requiring up to 100 watts of power.
If you’re two people traveling, one person can work at the table while the other drives. If you’re alone, you can wheel the vehicle to the nearest park or beach, set up the four support legs, and work all day. In 2016, I took my home office off the grid with solar panels on the window sills. 4 Ten years later, both the office and the solar panels have become mobile.
Images: Digital nomad office. Photos by Kris De Decker.
Image: Digital nomad office. Photo by Kris De Decker.
Renewable power plant
Although we built only one solar panel support structure, the handcart platform is large enough to support a total of four 100-watt solar panels. That would provide us with 400 watts of solar power for a concert or emergency power, for example. The handcart can also transport the two bike generators Low-tech Magazine has in Barcelona. 5Consequently, the cart enables us to quickly provide power within a radius of several kilometers, at any time of the day. The handcart could also be wheeled into a sunny spot during the day, charging a battery bank to power a household during the night and in bad weather.
Mobile home
If you want to get back home the same day, the handcart’s range is roughly 40-80 km (8-16 hours of walking, back and forth). However, at least in my case, nobody obliges me to come back home the same day. I could use the handcart for longer voyages, especially since it offers me a place to sleep.
The four supporting legs that make loading and unloading the cart more practical can also be used to turn the vehicle into a bed. After Kozimo went back to the Netherlands, I bought a foldable mattress that fits neatly on the platform. During a trip, I can store the other cargo under the cart at night. Alternatively, I could push a passenger who’s lying in the bed, turning the vehicle into an adult version of a baby stroller.
Images: A foldable sleeping mattress on the handcart. Photos by Kris De Decker.
Image: A mosquito net covers the handcart with a sleeping mattress. Photo by Kris De Decker.
Kozimo also made four supporting legs that are almost two meters long. I can use them to erect a tent around the bed, and cover the structure with modern tent materials, wool blankets, or a mosquito net. The large poles can also dry laundry. Furthermore, I could use the supporting legs in various combinations to convert the cart into a podium, expo stand, market stand, or a cinema or presentation screen.
The seat, table, solar panel, sleeping mattress, and longer poles can all be carried on the handcart simultaneously, leaving ample space for other luggage. That means that I could potentially work, live, and travel in the vehicle, turning it into a nomadic home. It fits somewhere between the tiny house on wheels, the tipi, and the homeless shack. Rents got very expensive in Barcelona, so I may as well give it a try.
Image: The handcart is packed for a longer trip. Photo by Kris De Decker.
Sailing and roller skating the handcart
Finally, Kozimo made a small sail for the handcart to help pull a heavy load in a good wind; the vehicle is sometimes used along the coast. Of course, we got the inspiration from the use of sails on the historical Chinese wheelbarrow. For a longer trip, the sail fits on the cart, so I could use it whenever the opportunity arises.
Images: The handcart with a 1m2 sail. Model: Iris De Decker. Photos by Kris De Decker.
We could increase the speed of the handcart by using a larger sail, and combining it with roller blades, inline skates, or a skateboard. In that case, the cart would pull the driver in good winds. It’s also possible to push the cart while using roller blades, inline skates, or an electric unicycle, without a sail. For now, we did a first small test on flat terrain using inline skates, with very good results. If you would take enough cargo, the kinetic energy of a skate-powered handcart would regularly pull you forward even without a sail.
The higher speeds of these configurations obviously introduce more risk and, most likely, trouble with the police. Higher speeds require ample space, free of pedestrians. That almost always pushes the handcart on the road, between the cars, as most cycle paths are not wide enough. However, it shows that sustainable vehicles could take many different forms if only we would give them the space to flourish. There are more than enough roads suitable for sailing and roller-skating handcarts; we need to empty them of cars and vans.
Images: Julia Steketee drives the handcart on online skates. Photos by Kris De Decker.
Handcart design and construction: Kozimo, Guilhem Senges.
Photos: Kris De Decker, Linda Osusky, Guillaume Lion.
You could build a handcart with stronger wheels, either heavy-duty wheelchair wheels (available up to 350 kg) or cargo-bike wheels. However, stronger wheels are likely wider, which increases rolling resistance. It would also become more difficult to push these heavier loads up a steep incline. ↩︎
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