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Solid gold minifigs still pending

23 January 2010 — dan

The moment I discovered that "Inanimate Reason" sell Lego-compatible components machined from aluminium, I knew I had to get at least a couple of pieces. If only to gaze upon, and sigh happily.

The two long beams are aluminium; the other pieces are standard Lego.

As you can see, everything fits. The holes are the right diameter and have the right little rebate around the edges; they're distinctly tighter to push pegs through than standard ABS pieces, but everything works as it should, and axles don't bind.

If you're a Lego purist, of course, then it is heresy to use "compatible" pieces of any sort - even Mega Bloks, the best of the usually-woeful Lego clones. It's a sin even worse than gluing pieces together (though probably not as bad as cutting them up). And if you're making something to enter in some sort of Lego contest, then non-Lego parts probably break the rules.

But if all you want to do is make cool things out of Lego, and you need, for instance, some long beams that won't bend as much for robot frame rails or something, these things are great.

(If you make large structures out of normal Lego, you have to use engineering skill to work around its limitations, which is a very educational exercise. Plastic in model-crane scales works not unlike steel in real-crane scales, so it takes real skill to build a huge crane or bridge (or, yes, short-lived house). Or, at least, a great deal of good old pre-scientific trial and error. But if you just want to knock together a chassis for a Lego Roomba or something, and no offensively gigantic Lego piece suits your needs, aluminium pieces are just what the doctor ordered.)

Inanimate Reason's products aren't even very expensive, by the standards of custom-machined gear. The smaller pieces only cost a few bucks each; my two 25-stud-length, 25-hole "liftarm" beams - the longest Inanimate Reason currently make - were $US11.99 each, plus a modest shipping fee.

The 25-length beams are not just stronger, but also about ten studs longer than any plastic beam Lego have ever made. I think the longest modern "studless" beam is the 15, unless you count the oddball 11-Duplo-stud-long one that came with this brilliant set. The longest old-style beam-with-studs is the 16. (And just because I know I'll get letters if I don't mention them, this very macho Scala building component is 18 studs long, and this recent bridge-frame piece is a gigantic 31 studs in length.)

Inanimate Reason have a Web shop here, and a BrickLink shop here. (Click "Show All Custom Items" for the metal parts - they sell normal Lego as well.)

Besides ordinary beams, they offer a variety of pieces in shapes and/or hole configurations that Lego don't make. You can get curved beams, beams with an even number of holes, holes with varying spacing to allow otherwise-impossible gear arrangements, beams with lockable hinges in the middle, heavy-duty shafting and gears for high-power drive applications, and adapters to let you easily use standard hobby servos in Lego machines.

(The abovementioned bizarre Early Science and Technology "Duplo Technic" line offers other possibilities for heavy-duty geartrains, but I think it's impossible to connect the chunky Duplo components to normal-sized Technic, and the sets are so rare and expensive that unless your intention is to force some Lego-robot-sumo contest to change their rules next year, you might as well buy the aluminium pieces anyway.)

Lego is already a surprisingly capable robotics prototyping system...

...but the bendiness of plastic means it can't get anywhere near the somewhat unsettling capabilities of "proper" modern robots.

Today, aluminium beams and drive components. Tomorrow, an all-stainless 8880!

(Or 928, of course.)

UPDATE: And now TechnicBricks has alerted me to the existence of Lego-compatible linear actuators, from this company. They integrate a motor and a linear actuator, come in two lengths, and work with both NXT and Power Functions.

They're expensive, though; one 100mm actuator costs as much as a whole 8294 Excavator.

Posted in Hacks, Toys. 6 Comments »

My Roman Army knife

8 January 2010 — dan

The other day I wrote about a knife switch that might actually be an antique.

Today, allow me to present a knife that could be 2000 years old!

It's not, though. It was probably beaten out of a bit of old leaf spring or something by some bloke in China only a few months ago.

It's about 235mm (9.25 inches) long when open, and cost me $AU11.50 delivered (about $US10.50, as I write this) from eBay dealer "The Medieval Shoppe" here in Australia. Here they are on ebay.com; here's a search that finds this "Rustic Foldable Iron Knife" in their ebay.com.au store (if they currently have any to sell), and here it is on ebay.com.

The wood of the handle was a bit rough and splintery, so I sanded it a little and applied some home-made beeswax polish.

The blade came with a usable edge on it. I straightened the edge a bit on a steel, then touched it up with my fancy sharpening doodads. It took longer than usual to remove a tiny amount of material, so the blade is probably pretty high-carbon steel. I wouldn't be surprised if there's a lot of variation in the steel used to make these things, though.

(I cordially invite readers to start a religious war in the comments about What The One True Knife-Sharpening System is. I'll start: If you're a beginner and/or clumsy, get a sharpening kit with some sort of angle guide, like the CRKT Slide Sharp or, for blunter blades that need more material removed, a Gatco sharpening kit.)

Even without extra sharpening, this slightly-mad-slasher-looking thing's not just a bit of renaissance-faire costume kit. It's a perfectly practical tool, with a nice slim blade profile that makes it good for slicing tasks, though not a great choice for really heavy cutting, and no use at all for prying things open. And if you were to hop in your time machine with it and go back to the Roman Republic, nobody would find it particularly remarkable.

Well, actually I suspect the cap on the hinge rivet may be a bit of aluminium or stainless steel, which'd be a giveaway if someone examined the knife closely. But apart from that, this is a decent ancient replica.

(You could be onto a nice little earner there, actually. Scour handle and blade with dirt for a while, soak it in wine, soak it in oil, put it in a low oven for a little while, then bury it in the garden and water it daily for a week. And then dig it up and put it on eBay with a $500 reserve as Roman Pocket Knife Miraculously Preserved In Peat Bog. Just hope they don't carbon-date the wood.)

More intelligent readers may have figured out, from this, that folding pocket knives have been around for a surprisingly long time. Fixed-blade knives are stronger (provided they have a decent-sized tang), and simpler, and so have always been much more common. But the ancient Romans did indeed have folding pocket knives - some of quite sophisticated design.

The ancient folding knives, and indeed every known folding knife until about the 15th century, don't "lock". The blade is only held open, or closed, by friction between itself and the handle. This design makes it easy for the knife to close unexpectedly and seriously injure you if you push the blade hard into something (or someone), or if you're cutting something and the blade jams on a push stroke. A simple friction-joint knife can also come open in your pocket; hilarity may ensue.

For this reason, it's now possible to get a variety of Swiss Army knives (find more with the SOSAK "SAK Selector"!) that have a proper lock for their main blade, and not just the standard "slipjoint" arrangement that resists opening or closing of the blade, but doesn't positively lock the blade in either position.

(And yes, I am aware that some law-and-order geniuses in the UK decided to one-up the similar geniuses here in Australia and make it illegal to carry any knife with a locking blade in a public place, unless you have a "good reason". The list of acceptable "good reasons" does not appear to include "not wanting to cut my own fingers off, or stab myself in the scrotum while running for a bus".)

I wouldn't be surprised if someone 2000 years ago came up with at least a simple locking mechanism for a folding knife - like the rotating collar on the classic Opinel knife, for instance. A sliding ring, a peg that goes through holes in the handle and a slot in the blade; there are lots of possibilities that wouldn't require the precision fabrication techniques and tough steels upon which modern locking knives depend. But if someone did come up with a locking folder in 100 BC, it apparently didn't catch on.

(It's possible that many such knives were made, but didn't survive to the present day. Iron and steel items of all sorts are hard to find in archaeological digs, because iron easily rusts away to nothing over time, leaving archaeologists puzzling over the stain the rust left, and whatever parts remain, to figure out what the now-lost iron parts looked like. Older bronze-bladed knives and swords often fare a lot better. Early iron blades were actually clearly inferior to the bronze alternatives; iron was much more common than the copper-and-tin used to make bronze, but until we figured out how to make proper steel, iron swords were made of wrought iron. That material makes dandy door hinges, but lousy blades.)

My replica has a neat pseudo-lock system, though:

There's a flattened spike on the back of the blade that stops it from opening too far, and is also easy to grip when you grip the handle, and thereby prevent the blade from closing. It's not a real lock, and it sticks out awkwardly when the knife is closed, but as a safety feature it's a lot better than nothing.

(The spike also has a little hole in it, through which you could tie a lanyard.)

Making your own knife, often from some cast-off piece of steel like an old file or a railroad spike, is a popular simple metalworking/blacksmithing project. I think a lot of people are put off the idea, though, by thinking they have to make something that's somewhere near modern commercial quality, or at least as good as a Douk-Douk or K55K.

You don't, though. You can make a knife like this with basic hand tools, a gas stove and the very cheapest of eBay Anvil-Shaped Objects, if you've already got a chunk of steel.

Or you can just buy one, of course. Either way, it's another very satisfying object.

Posted in Handicrafts, Toys. 11 Comments »

Are you troubled by yellowed, lifeless Lego?

18 December 2009 — dan

There I was, idly scanning eBay for Lego baseplates to maybe give to one or another child for Christmas (HOW CAN THEY NOT MAKE CRATER PLATES ANY MORE WHY WAS I NOT CONSULTED), and I noticed that most, if not all, of the plates on offer weren't very close to their original colour.

This reminded me of a thing from the other month about de-yellowing the casings of old computers and video games.

If you don't want to paint over the yellowed plastic, you can soak it in a hydrogen peroxide solution, with a dash of one or another kind of bleach. (Note that the popular "oxygen bleach" products are based on sodium percarbonate, which when added to water just gives you hydrogen peroxide plus washing soda.)

If you want to get fancy, you can make a gel concoction dubbed "Retr0bright", which'll stay where you put it. So you can bleach things without having to remove all the electronics so you can dip the casing, or bleach the outside of a thing but not the inside, et cetera.

Apparently even plain few-per-cent peroxide will often do the job if you leave the pieces to soak overnight. If you want faster results, you need 10%-to-20% peroxide, which you may or may not be able to get from a pharmacy.

(I must, at this juncture, digress and recommend Armadillo Aerospace's old video - 56Mb MPEG here - of what happens when you put high-test rocket-fuel-grade hydrogen peroxide on various common substances.)

Does this technique, I wondered, work on Lego?

Apparently, yes, it does! Even on clear pieces!

(Bleach can apparently attack the paint on some printed bricks, though.)

I don't think this will actually do the plastic any harm, either. Or any more harm, anyway. The reason why plastic discolours in the first place is because something - ultraviolet light and/or atmospheric oxygen, usually - reacts with one or more of the constituents of the plastic. The material that yellows may be the polymer itself, or it may be flame-retardant additives, or plasticiser, or something. In any case, bleaching already-damaged substances back to white shouldn't do any more damage.

[Update: I just remembered that a couple of years ago I wrote this piece, about the making of Lichtenberg figures in clear acrylic. It involves a rather unusual way to discolour plastic.]

You don't have to bother with this at all, of course. A yellowed Amiga 500 is still an Amiga 500, and yellowed Lego is still Lego. Some builders have even...

...used yellowed pieces to "weather" models!

Posted in Handicrafts, Nerdery, Toys. 8 Comments »

Give the (free) gift of The Secret Life of Machines!

1 December 2009 — dan

A quick update on the subject of the Secret Life of Machines series...

...which, for the information of newcomers, is

1: fantastic,
2: legal to download for free, and
3: large.

A couple of years ago, I made a torrent of a high-video-quality version of this excellent science series, which total 3.3 gigabytes.

Of late there have usually only been one or two seeds for the torrent, though, and one of them is me, and my little home DSL account can only upload at a peak speed of about 25 kilobytes per second. So it takes me a couple of days to send the whole bulk of the three series to someone (technically, it's two six-episode series of The Secret Life of Machines, plus one six-episode series of The Secret Life of The Office). And when the transfer finally completes, the recipient will then usually not bloody seed it.

So if you've still got that torrent sitting in your BitTorrent client, I'd be grateful if you force-seeded it for a while.

(A reminder for readers who're dubious about this, or protection-racketeers from one or another content company who're champing at the bit to send me a nastygram: Tim Hunkin, the creator and principal presenter of this show, wants people to download it for free. He makes this clear in many places, like for example his pages for the three series of the show. The shows are still copyrighted, but free distribution is expressly permitted.)

As I've mentioned before, you can help out with seeding even if you don't have the torrent in your BitTorrent client any more, provided you still have the files. (Which, by the way, are in the "M4V" iPhone format, are not nasty VHS rips, and are playable on all platforms; use VLC if you have problems.)

To seed if you've got the files but not the torrent, just get the torrent started as if you were going to download it again (so your BitTorrent client creates the appropriate download directory and empty files), immediately stop it again, copy the video files from wherever you've put them into the new download directory over the top of the new empty files, and then restart or "Force Re-Check" the download (depending on which BitTorrent client you have). Provided the files are the right ones for this iPhone-format version of the series, and have the right names, the download will now be 100% complete and you can force-seed it for a while.

Oh, and don't worry if your BitTorrent client says the download is only something like 99.8% complete, and it has to download a bit of data before it's "finished". That just means your computer has modified some header data in one or more of the files, so that tiny bit needs to be re-downloaded to overwrite the changes. It doesn't mean the files are corrupt.

(If you don't have a BitTorrent client at all but do have the files, perhaps because someone gave them to you on a thumb drive or something, you can also help out. You just need to install a client - µTorrent, for Windows and Mac, is excellent - and then do the starting-stopping-copying-and-then-seeding thing. The default settings for a freshly-installed BitTorrent client may stop it seeding after it's uploaded 200% of the data size of a torrent, or something; upload-ratio checking goes weird when you do the stop-copy-and-seed thing, too, because you'll have the whole download but won't have actually downloaded anything. Just right-click the torrent and select "Force Start" or "Force Seed" or whatever it's called in your client, to ignore upload limits.)

Here's a magnet link for the Secret Life of Machines torrent. (You may need to associate your BitTorrent program with magnet:... links to make this work, or manually copy and paste the link into an "Open Torrent..." dialog.)

You can also download the torrent file from isoHunt or The Pirate Bay - it was on Mininova, too, but they decided to go legit the other day and removed pretty much all of their torrents, including legal ones like this.

The BitTorrent community is moving away from .torrent files, just as it's moving away from trackers - The Pirate Bay have actually shut their trackers down altogether now. If you've got the little magnet URI for the download you want - it's ?xt=urn:btih:D62CLPSEYNRN74FRZDUC5GYVKTOOUKGE for the Secret Life of Machines torrent - then your BitTorrent client can use it to get other people who're downloading the same thing to send you the data that a .torrent file would have given you. This may take a little longer than downloading a torrent file would have, but it shouldn't actually fail unless there's nobody seeding the torrent, in which case you obviously wouldn't be able to download it anyway.

Once you've got the torrent info, the distributed hash table (DHT) system that all modern BitTorrent clients support can go on to give you the rest of the data from other users, without needing a central "tracker" system to keep everything organised.

And then, before you know it, you're watching Tim stand on the accelerator and the brake at the same time, and Rex brutalising that poor innocent refrigerator.

Tim Hunkin has done a lot of stuff since The Secret Life of Machines. Here's...

...some posh bird enjoying the latest in Tim's long and inimitable line of penny-arcade amusement machines, "Whack A Banker".

Posted in Electricity, Hacks, Nerdery, Science, Toys. 24 Comments »

Just your everyday Klötzchenbeförderer

9 November 2009 — dan

Via TechnicBricks, yet again:

This magnificent contraption is not new - the clip's from 2007, and Make noticed it in early 2008. But I think you'll agree that its creator, "superbird28", could do with some more publicity.

If you'd prefer a more compact version:

This reminded me of another Make find, just the other day:

This is a system used in real factories, to reduce the machinery needed to handle different goods, or the same goods at different stages in the manufacturing process. Note that the cylinders and the cubes don't mix.

Posted in Hacks, Machinery, Toys. 4 Comments »

Perhaps I'll use it as a doorbell

8 November 2009 — dan

If you had to name one electrical component that just shouts "mad scientist", the knife switch would be that component.

(I'm not counting the Jacob's Ladder as a "component", here.)

Connecting lightning to your not-yet-animated monster, activating your death ray, powering up the time machine; all jobs for a big old two-blade knife switch.

Knife switches have plenty of actual practical uses in the real world. Even small ones can switch very high current, their position is obvious at a glance, and they can put up with a lot of abuse. They're obviously not a great choice for high-voltage switching, but they'll usually actually do that very well too - you just have to stay away from the live bits.

(Knife switches made for really high-voltage operation often have special spring-loaded doodads that stay connected as you raise the knife-bar, then snap up very quickly. Their purpose is to break the contact very rapidly, so you don't pull an arc between the terminals.)

So naturally I had to get one. And not one of the little plastic science-classroom versions with binding posts or spring terminals; I wanted something beefy, as were and still are used to isolate radio gear from the big lightning-attracting antenna outside. A knife switch also makes a dandy automotive battery isolator, but I didn't want one of those, either.

After a year or two of e-mails from my saved eBay search, I found just the thing.

This handsome object cost me $AU28.11 delivered, which I thought might have been a bit too much, until it arrived. I now realise I got a bargain. This thing's way cooler than I expected it to be.

All of the terminals and contacts work OK; a couple of the hefty terminal screws were seized and remain tight after cleaning and oiling, but this is a perfectly functional piece of gear.

The Bakelite-slab base is only about 14 centimetres square (5.5 inches), but the whole assembly weighs about 1.86 kilos (4.1 pounds). And it's surprisingly complicated.

Your standard two-blade knife switch is simple enough. It's either a dual-pole, single-throw, or a dual-pole, dual-throw (if you don't know what this means, check out the Wikipedia article on switches).

This thing, in comparison, is a freakin' logic puzzle.

It's got six terminals, and two separately hinged - but electrically connected - blades. The worn (and now lightly polished!) wooden handle is in two parts, too, one for each blade. But the two handle parts form a rebate joint.

This makes it possible to have both blades down, both blades up, or only the left blade up. But, because of the rebate joint, you can't have the right blade up and not the left.

Let's number the terminals clockwise from the one at the bottom right of this picture. So the one to its left is terminal 2, terminal 3 is the one on the back connected to the bases of the blades, and so on to number 6, which is partly obscured by the wooden handle in the above picture. Pay attention, there will be a test.

With both blades up, terminals 1, 2 and 6 are connected to nothing, and terminals 3, 4 and 5 are connected to each other.

With the right blade down and the left blade up, terminals 1, 2, 4 and 5 are disconnected, while 3 is connected to 6.

With both blades down, terminals 1, 3 and 6 are connected to each other, and terminals 2 and 4 are connected to each other; only terminal 5 is no longer connected to anything.

(If you can't quite see how that is the case, note that the middle section of the left blade, the lower one in the above picture, has a copper sleeve around it that's insulated from the blade itself. When that blade's down, the sleeve connects terminal 2 to terminal 4, but not to the blade itself.)

Oh, and terminals 1 and 6 are connected to the blade contacts via a couple of bits of might-perhaps-be-fuse-wire-but-probably-isn't. So you could easily connect either or both of them to some other part of the assembly, if you wanted.

(Does anybody know of a piece of software that'll take a description like this - "in state A, these parts are connected, in state B, the situation changes to this", et cetera - and will then draw you a diagram? I started drawing it out by hand in a flowcharting/circuit-diagram program, but then realised I had no idea how to draw these crazy ganged switches.)

The baseplate bears a little oval plaque that says:

VICTORIAN RAILWAYS

ELECTRICAL ENGINEERING BRANCH

WORKSHOP SPENCER ST.

(It just occurred to me that the switch could easily have been used for switching railway signals of some sort. The rebated handle interlock could be for something like preventing green lights for both directions on one line.)

I actually will use this switch as a switch, from time to time. But when it's not in use, I think I'll hang it on the wall somewhere.

Posted in Electricity, Nerdery, Toys. 15 Comments »

Lego news for the inattentive

22 September 2009 — dan

The original poster of the MetaFilter Space Lego article I mentioned in passing in the last post didn't explicitly mention something, so I suppose I'd better:

Lego are making Space sets again!

More or less.

(I originally started writing this as another comment on the MetaFilter page, but it turned into a whole big thing so I fluffed it up into this blog post. Regular readers may find this a bit repetitive, but there's got to be something on this blog for people who've just stumbled in, looking worried and trying not to make eye contact with the regulars.)

For many years now, Lego have had space... ish sets, like the Life On Mars and Mars Mission series, and the older UFO line.

Now, though, they've got a new Space Police line, which is very close to being good old-fashioned Space Lego.

The first Space Police sets came out a year or three into my own Lego "Dark Age" (the period of time between when a person gets too old for Lego, and when the same person gets old enough to start playing with it again). They were clearly Space sets, just with a few new pieces and a different colour scheme.

(Lego's most ~~offensive~~ striking current colour scheme is on display in the interestingly-Technical-under-the-skin Power Miners line. Lime green and Day-Glo orange, baby!)

Lego entered their own Dark Age shortly after the first Space Police sets. In the 1990s, they spent a lot of time making sets that were difficult to love, because they had lots of special-purpose pieces. They even made "juniorised" sets that were, in essence, Lego for kids that didn't actually want to play with Lego. Those sets contained many complex single pieces that should have been assembled out of several other pieces - see this post for a particularly egregious example.

They're much better now, though. Lego still have a few licensed lines that us oldies usually don't much care for. Personally, I think almost all of their Star Wars sets look awful; I think Star Wars ships just don't look right in Lego, except in the large scale used in the multi-hundred-dollar flagship sets. And then there are the "Bionicle" action-figures-made-from-Lego that also have little appeal to most adult Lego fans - though the skeletons of Bionicle figures are very Technic-y, with many very useful pieces. Technic itself has changed a lot, though not actually for the worse, if you ask me.

But Lego have also gotten back to their roots, and now make plenty of good old-fashioned sets, large and small, full of general-purpose pieces just like in the old days. (Except the packaging is flimsier, with none of the useful old blow-moulded plastic trays; now it's just a box full of plastic bags of pieces.)

There are now many fantastic midrange sets with only a barely higher percentage of specialised pieces than there were 25 years ago. And there are also sets that could have been sneaked into the 1982 catalogue without looking out of place. Look at the #6192 Pirate Building Set, for instance. Lego has an actual two-piece shark now, which looks hilarious with some frickin' lasers on its head but isn't general-purpose at all. There's nothing it can possibly be except a shark with a few connecting studs. But the Pirate Building Set's shark is a cheerful-looking blocky creature made from several separate pieces, in the old style. (See also that set's catalogue-number-adjacent relatives, the Fire Fighter and Castle Building Sets.)

If that's the kind of Lego you like - or just the kind you want to buy for your kid - then you can ignore the licensed stuff and just get the new-old-style sets. You don't even have to buy sets you don't much want just because they contain pieces you need for the model of your dreams: There's an auction site just for Lego full of enterprising dealers who part out sets and sell the pieces separately. So you can, for instance, buy a few yards of the new chunky track pieces, and the sprockets to drive them, surprisingly cheaply.

I also harbour a great affection for the current "pocket money" sets, that give you just a minifig and a smattering of accessories. A better way to inexpensively start to tease other grown-ups out of their own Dark Ages has not yet been discovered.

There's this cop and his dog, this street trader, this brand-new Space Police officer, this garbage man, this builder, this fireman, this street cleaner (with one of those uncommon rubbery brushes), this kayaker, this God-bearded (Shark!) wizard, this knight, this mailbox robot, this troll, and this little spaceship. (Note that the pre-2009 sets are no longer likely to be available at your local department-store-with-a-Lego-section.)

My absolute favourite, though, is the pirate with a fish on a stick, and an extremely minimalist campfire.

The pirate's opposite number is much better armed, but that brave smile cannot conceal the obvious fact that he's having a lot less fun.

Posted in Nerdery, Toys. 23 Comments »

Now do crosswords

23 August 2009 — dan

Hans Andersson is a fellow who made a Lego Rubik's Cube solver (which, amazingly enough, is only one among many).

He has now gone one better.

Possibly quite a lot more than one better, actually.

Yes, this is a Mindstorms NXT robot that solves sudoku. It's got pretty good penmanship, too.

Like the Lego 3D scanner, Andersson's new creation isn't what you'd call the fastest of robots. But if you're not in a hurry, I'd say this robot does its job considerably better than the also-amazing Lego movie projector.

(Via, once again, the excellent TechnicBricks.)

Posted in Nerdery, Toys. 8 Comments »

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