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Comment Re:Don't Miss The Point (Score 2) 105

Services like that exist online, and they're excellent, albeit rather slow. I personally use iMaterialize because they have such a wide range of material options (everything from rubber to titanium) and finishes (for example, 4 different options for silver), but there's lots of others out there, and some are cheaper.

If you've ever played around with 3d modelling, I definitely recommend giving 3d printing a try, even if just a little test piece. :) Note that plastics are a lot cheaper than metals, although metals look the coolest.

Comment Re:Novelty (Score 1) 105

What sort of 3d prints are you looking at?

Perhaps my expectations of 3d printers are too high because I buy from professional 3d printing services rather than using a low-end home 3d printer. They use high end products and sometimes do post-printing finishing work. But the quality of the stuff you can get is truly excellent, and out of a very wide range of materials.

Comment Re:This is so 2012. (Score 1) 105

Isn't that now the limiting factor?

So we have 3d printers in stores. Now we need all of the home devices that could potentially need spare parts printed to be available online, preferably in a unified database. You need manufacturer buy-in. Maybe some sort of certification mark that manufacturers can stick on their devices to show that printable replacement part models are freely available. I could use a new cheese compartment door in my fridge right now, for example. And I live in Iceland where shipping times are long and shipping costs / import duties high, so it'd make time and economic sense to print, too. But while having a 3d printer would be great, if the model isn't available, how does that help me?

Of course some companies, like iRobot, rely on profiting off of selling their spare parts.

Comment Re:Wrong type of machine for Dremel (Score 1) 105

It does seem rather weird to treat it as an intractable problem. Are we really talking about something that's AI-Complete here, like natural language understanding? Something not succeptible to a combination of chained rules, physics calculations, and statistical analysis? I seriously doubt it. So different machines can act differently due to wear, etc? Gee, people have never written programs to deal with that before, heavens no. So some things may require a decision from the operator, like whether to restart a defective piece or try to salvage it? Gee, I've never heard of a program asking the user a question during operation before! A piece of "printing" hardware experiencing a jam of some kind and needing manual intervention? Gee, nobody has ever experienced that one before!

I'm not saying that CNC machines and 3d printers are equivalent and that you can just swap a CNC machine in to the sort of role 3d printers are intended for. Of course the task of gouging out steel with power tools is a more intensive one than writing out plastic in layers with a slightly more advanced version of a hot glue gun. But we're not talking about creating superintelligent cyborgs here, we're talking about analyzing physical processes, including their various failure modes, and when a decision or action is required, presenting the user with the information needed to do that.

Comment Re:This is so 2012. (Score 1) 105

Oh, and in #2, sound insulation would also be very important, both for the compressor (if compressed air is used, rather than bottled oxygen) and for the jet itself (which is basically like a tiny rocket engine). And I guess the filter isn't just about removing any incomplete combustion products from the exhaust, but also any dust or the like.

Even if it ultimately isn't suited for, say, a quiet home office, 3d printing isn't really an home office task, we're more talking about a "garage workshop" sort of thing. I'm just curious whether anyone has pursued such an approach, because at a glance it sure looks to have potential for making a very broadly capable product. I mean, such a system should even be capable of printing electronics, including resistors, capacitors, etc, maybe even some types of batteries (not anything requiring extreme precision, like a CPU, and li-ion batteries would be right out due to the thin, sensitive and rather complex membrane needed, there's no way you could just deposit that, but still..).

Comment Re:This is so 2012. (Score 1) 105

There's two types of processes that I'm surprised I've not seen more focus on.

1) Printing of, and then filling of molds, which can then be melted down and reused. That's how the higher-end 3d printed parts that you can buy online made, including almost all 3d-printed metal parts you get from online 3d printing services (the extra steps for metal being to coat the mold in a ceramic shell and melt away the mold). The only commercial 3d-printed metal that I'm aware of that doesn't work in this manner is iMaterialize's titanium, which uses laser sintering - and it has an out-of-this-world price tag.

It seems to me that if you used a mold, while in several ways it complicates the process (extra steps, preventing adherence to the molded object, etc), in others, it simplifies it. Your print heads don't need to handle a variety of materials or produce a pretty or durable product. They still need to be able to produce fine surface details but the ability to print thin structures loses importance. Once you've got a mold, you open up the floodgates to the sort of products you can fill it with, anything that will harden either through cooling or via chemical reaction, anything from thermoset plastics to candy.

(note I'm not envisioning a little hobby home printer that fills molds with molten metal in your office, mind you... although I could envision a more garage-scale or small industrial scale version that could handle such a task)

2) I've never even heard of a 3d printer being based on thermal spraying. With thermal spraying, you can choose the balance of precision vs. flow rate via nozzle size. Your materials are virtually unlimited, pretty much anything you can turn into a powder. It could conceivably even let you work with metals in a home environment, if the rate was kept low enough that heat buildup wouldn't be a problem (and you'd want an air filter on the exhaust, even though it should be pretty clean). You can choose the temperature and velocity you're spraying at by varying the pressures of compressed air and combustible fuel fed into the chamber with the powder, so you can work both with heat-sensitive and heat-requisite materials, as well as materials that can't stand high velocity impacts and materials that require them. Such a system could likewise do more than just print - it could add and then sectively remove substrates, it could engrave, it could change surface textures by sandblasting/polishing with various materials, it could paint or apply high-performance coatings - pretty much anything you can envision from a device whose fundamental workings are "shoot grains of material of your choosing at a velocity of your choosing (1-1000+m/s) and temperature of your choosing (cold to thousands of degrees)".

In both cases #1 and #2, I'm genuinely curious as to why there's not been more work done with them. Or perhaps there has been work done with them that I'm unaware of? I'm asking as someone who makes and buys 3d printed items online but has never printed one herself.

Comment This is how it had to be (Score 1) 188

You can't unwind the tentacles of the military-industrial complex all at once. You also can't ignore SpaceX and how well they have been doing.

This award is simply acknowledging reality. Boeing has to get some pork to keep the lobbyists happy, SpaceX has to get some money to keep them in the running. It will be a slow shift over time as SpaceX continues to deliver for less money.

SpaceX is playing the game... why do you think they are opening a spaceport in Texas? Gotta spread those jobs around to keep Congress happy.

The funny thing is, you can play that government game and get rich while still delivering an excellent product (SpaceX). It takes several generations of bloated military contracts to teach people to stop working so hard (e.g. Boeing, Lockheed Martin, etc).

Comment Farmers != Farm Workers (Score 0, Troll) 122

The headline says farmers. The text says farm workers. Very much not the same thing. A farmer is the owner of the farm. A farm worker is generally a hired hand, often (though not always) a migrant, and if so typically from Mexico or farther south.

The story suggests that the multi-drug-resistant bacteria are the result of antibiotic treatment of the animals at the farm. This misses another possibility:

In Mexico, most antibiotics are over-the-counter, much like asprin here in the US. People who feel ill or have some infection often buy and take them. Typically they use them until they no longer show symptoms - then stop, rather than taking a full regimin and killing off all the bacteria. (Why take more of the non-free drug once the symptoms are gone? Waste of money, right?) This is a recipe for creating drug-resistant bacteria.

Of course if an infection is resistant to one antibiotic, a paitent is likely to try another, and another, and so on until they find one that works. THAT's a recipe for maintaining and improving the bug's resistance to the front line antibiotics while breeding resistance to others.

As a result, a substantial fraction of the workers arriving from south of the Mexican border are carriers of multi-drug-resistant baceria.

Meanwhile, a farming operation is likely to give a limited number of antibiotics continuously, so non-resistant infections are wiped out before they can develop resistance, and if they do develop resistance it will be to the particular drugs used, rather than the universe of antibiotics.

Of course, infected workers can infect livestock, just as livestock can infect workers. And infected workers can trade infections around, just as livestock can. (More so, since the livestock tends to be kept separated, to reduce both disease spread and breeding by unintended pairings, limitations that farmers can't impose on their workers - and would be unlikely to try even if they could.)

So it seems to me that responsible researchers would go a bit farther before reporting: Like by doing genetic testing on the strains of bug in the various workers and the livestock, and running models on the results to try to identfy whether the bugs are from the herd or the workers.

I don't see any such work alluded to in this popularized reporting. It seems to just assume that the bugs were developed on the farm and spread to the workers. I hope this is a disconnect between the actual research and the report, rather than an accurate characterization of the research.

Comment Especially: The paint. (Score 1) 113

The gas bag itself was flammable; it wouldn't have mattered what gas was in it, when it disintegrated

In particular: The paint. It contained a mix of powdered aluminum and iron oxide pigments, in sufficient concentration to maintain a redox reaction.

You and I know this mixture as "thermite". It's really hard to get the reaction started - but an electric discharge can do it. (They tried to tether it with an electrical storm approaching. That would make one hell of a spark when the charged envelope comes near to connecting to the grounded mast - which is about when the fire started.) Once it's started, the reaction is essentially impossible to extinguish. The aluminum steals the oxygen from the iron oxide. The heats of formation of the two oxides differ so much that the energy released leaves the resulting elemental iron as an orange-glowing liquid and the aluminum oxide incandescent white-hot.

Comment That is a misreading of the Supremacy Clause: (Score 4, Informative) 213

You are bound by the treaties your country signed.

Yes: You, and the states, and their courts, are bound by them (to the extent they are clear or were implemented by federal enabling legislation).

In fact, they have more legal weight in the US than laws passed by your own Congress.

NO! They have EXACTLY the same weight as federal law. Both treaties and federal law are trumped by the Constitution, and both are also creatures of Congress, They can be modulated, and destroyed (at least in how they are effective within the country) by congressional action.

The idea that they're any stronger or more permanent than federal legislation comes from a (very common) misreading of the Supremacy Clause:

This Constitution, and the Laws of the United States which shall be made in pursuance thereof; and all treaties made, or which shall be made, under the authority of the United States, shall be the supreme law of the land; and the judges in every state shall be bound thereby, anything in the constitution or laws of any state to the contrary notwithstanding.

This says that the Constitution, Federal Law, and Treaties trump state law in state and federal courts. It says nothing about the relative power among the three.

The misreading is to interpret "all treaties made ... shall be the supreme law of the land ..." to mean that treaties effectively amend the constitution. This is wrong. You can see it by noticing the same kind of misreading also makes federal law equivalent to a constitutional amendment - which it clearly is not.

In fact the Supreme Court has spoken on the relation between the Constitution and treaties: In Reid v. Covert, 354 U.S. 1 (1957), the Supreme Court held stated that the U.S. Constitution supersedes international treaties ratified by the U.S. Senate.

Treaties are abrogated, at the federal level, all the time, and there are a number of mechanisms for doing so.

Comment Re:I just want the new Nexus. (Score 1) 222

There are three professions where being untruthful is the key to success: Lawyers, salespeople, and marketing. All three are hired to portray their client in the most favorable light possible, and the very best ones lie through their teeth. The worst of these three are the marketers because they have legions of psychologists and scientists trying to figure out the best way to lie to people.

Yes! You're both presenting a perfectly defensible argument against marketing and reinforcing my original point! Because geeks tend to abhor marketing, we dismiss its significance, and are perennially gobsmacked as to why an intrinsically emotional, manipulatable species is so susceptible to emotional manipulation.

So long as humanity is what it is, reason will only ever get you so far. You either need to blow the doors off with a staggeringly amazing thing, or come to terms with the fact that every single entity who might care about your thing has feelings, and bending those feelings in your favor can work wonders.

It's not all bad, though; emotional manipulation works under much the same constraints. Unless you're a Level 80 Snake Oil Salesman with a hat full of luck, you're going to have a very hard time making your thing last if it doesn't live up to the hype--and your reputation will suffer for it.

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