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Comment Awful lot of money for some big flaws... (Score 5, Informative) 37

This is a pretty cool concept and a good start, but like consumer 3D printers from five years ago, it is not really practical or cost effective. The biggest problem this thing has is the $2199 price tag. Holy crap! Anybody can already make better quality circuit boards using a cheap laser printer, a blacklight, and some basic supplies. You could even build a DLP projector-based photolithography setup with great resolution for half that price, and people have done so. It just doesn't cost anywhere near $2199 to make good circuit boards.

That brings us to the next big problem: this thing doesn't make good circuit boards. Conductive ink is not a real substitute for solid copper traces. The traditional etched-foil method ensures uniform and predictable trace properties, and the solid copper has great current carrying capacity and low resistance. That matters a lot in many applications. Good luck handling tens of amps (or even more) in a switching power supply using conductive ink for traces.

But then there are the holes. Or lack of holes. This thing doesn't drill holes, and it's intended to create boards with no holes at all. It makes "double layer" boards by overlapping insulated conductive traces applied on the same face of the substrate. That's clever and a very cool idea, but it's no substitute for drilled holes and two planes separated by the substrate itself. I would have very little confidence in wire attachments made to this type of board, and it definitely is not suitable for applications with any serious voltage differential between layers, or where impedance control or stray capacitance matters. In other words, it's limited to a small and low-performance set of applications. No multi-megahertz digital signals. No RF circuits. No high voltage (or even line-powered) stuff. No high current handling. For $2199, I'll wait a decade and see where this tech goes.

Comment Maybe don't assume all readers are idiots. (Score 4, Insightful) 55

"To achieve the breakthrough, the UW team used a material commonly found in commercial lasers but essentially ran the laser phenomenon in reverse. They illuminated a single microscopic crystal suspended in water with infrared laser light to excite a unique kind of glow that has slightly more energy than that amount of light absorbed."

That is the most detailed explanation in the article of what this phenomenon is and how it works. No names, either for the phenomenon or the materials involved. No numbers, or even quantitative comparisons. No links to the actual research. Who do they think reads this stuff? Random people aren't looking at long-form articles on research posted to university websites. Their whole audience would appreciate a lot more detail than they're giving us.

Comment Re:Why (Score 1) 965

There's a big difference between preparing for the possibility (you don't seriously believe there will never again be war in North America, do you?), ...

"Never" is a very long time.

Will there be a war next week? Probably not (99.999%). Next month? Next year? In the next 10 years? 20 years? 50 years? Have you died of old age or heart disease or such by that time?

100 years? 200 years? 500 years?

Who knows? Destabilization happens fast, and the prelude is usually only obvious in hindsight. The prepper philosophy is to admit that nobody can answer your question and to take some degree of precaution as a hedge against the risk.

Comment Re:^^^^^ MOD THIS UP ^^^^^ (Score 1) 161

Don't look at sun with remaining good eye. And sunlight isn't coherent light, so the comparison is skewed from the start. I recommend that you try looking into an eye-safe laser beam from a few hundred yards away (so the energy of the beam is spread over a spot two to three feet in diameter). The experience will not be dangerous, but nevertheless quite unpleasant, and this little experiment should cure the misconception that looking into a laser from afar couldn't be a problem.

Obviously the lack of temporal coherence in sunlight is irrelevant here. Spatial coherence does have some influence on how bright the source appears. Sunlight is fairly spatially coherent at about 4.7mrad divergence on Earth. That's comparable to a bad laser pointer, and not too much worse than a good one. Coherence is much less important to this issue than M^2 value or other measures of beam "quality" that correlate to focal spot size. The sun wins on those metrics. I've stared into many laser beams of different powers and wavelengths, sometimes intentionally, occasionally accidentally. I've been on the receiving end of high power beams from long distances just to see what it's like. A 150mW 532nm beam of about 1.5mrad (a decent quality DPSS module) is pretty darn bright from 3/4 mile away at night, but it's definitely not dangerous. Try it.

Comment Re:Why (Score 4, Interesting) 965

To the point, militant Islam really, really wants to be in charge, which makes pretty much everyone in the world either an immediate target or a future target. It's odd that you don't seem to recognize that.

Militant Islam isn't a single entity, it's an ideology followed by many competing groups. The attacks happened because someone, or some group thought it would further there goals. They thought it would be a better use of resources than attacking the US, or Hungary, or keeping fighters in Syria (and they might be correct, or they might not be correct, but they thought it would be a good idea). So the real question is, who are these people making decisions, and why did they make those decisions? It's odd that you don't seem to recognize that.

That's like asking why the Nazis chose to invade Poland when they did, looking for some deep meaning or hidden complexity. They wanted to control it - along with everywhere else in the world. It was an easy target, so they hit it. When the goal is total subjugation of all targets, the rationale for which targets are selected first is sort of irrelevant.

Comment Re:Why (Score 5, Insightful) 965

How many "preppers" are there in the U.S. that believe the West is going to collapse into ruin any day now. All it will take is just the right spark to start the race/culture/religious/civil war.

There's a big difference between preparing for the possibility (you don't seriously believe there will never again be war in North America, do you?), versus believing you can bring it about yourself. Preppers recognize the reality that stable, peaceful societies never last forever and often devolve quickly without enough advance notice to avoid the fray. Terrorists believe they can cause that devolution.

Comment Re:Always had a problem with laser pointers (Score 5, Informative) 161

Most laser pointers are class IIIb laser devices.

IIIa, not IIIb. The CDRH requires that handheld pointing lasers meet the IIIa classification, which means less than 5mW output power among other things. Red laser pointers virtually all comply with this. Green pointers are hit-or-miss, since the cheap DPSS laser inside has highly variable power output depending on unpredictable factors. In my experience measuring the power output of green pointers (and I've measured a lot of 'em), they are generally 3-5mW but sometimes you get a hot one that pushes 5-10mW. They can all be cranked up with tinkering though, sometimes to 100mW or more! It's the tweaked green pointers and black-market IIIb and IV devices that cause some concern. 5mW in the eyeball is extremely unpleasant, but does not cause retinal damage - especially with the poor beam quality (and thus large focal spot size) of handheld lasers. A tweaked-out DPSS pointer running tens of milliwatts can definitely cause instant permanent damage at short range though, and the 500mW to 1.5W blue diodes are quite dangerous (but totally awesome).

Here's the thing, though: None of these lasers are really dangerous at long range. The beam quality is universally terrible, which results in high divergence and therefore large beam diameter at long range. The total amount of light produced by even the most powerful handheld lasers is not very much, and quickly loses its brilliance when spread over a circle a few meters in diameter. At one mile, a 2mrad beam will be approximately 10 feet in diameter. A 1W laser would then have an intensity of 0.138W/m^2, or 0.0138mW/cm^2. That's nothing. The sun is over 100 times brighter than that.

Comment Re:Ground to plane windshield geometry (Score 1) 161

I'm curious how someone on the ground is able to aim at the windshield of the cockpit from the ground.

What am I missing here?

You're not missing anything. It's very hard most of the time to hit the windshield of an aircraft from any nearby point on the ground. The hardest part, though, is keeping the laser pointed at the target. It's essentially impossible. People have tested this repeatedly - it's on YouTube. The bottom line is that a handheld laser can only ever manage to very briefly flash the cockpit of a flying aircraft, and the beam intensity at such a range is non-dangerous even if the laser is quite powerful. It may be surprising to a pilot and could cause a brief but dangerous distraction, but the hype of blindness (even temporary vision loss) is grossly exaggerated. Basic math and empirical testing shows that pretty conclusively.

Comment Re:"Strong indication" (Score 1) 190

"Strong indication... likely..."

So, are they priveleged or not?

They are.

There are a lot of people in US prisons, you know, and if there is such a thing as an unpriveleged inmate/attorney conversation (I have no idea how it works), then there are probably a lot of those going on.

There isn't.

What if they call the attorney's office and they're not there? Is that priveleged?


All communications between an attorney and client are privileged, with a tiny set of exceptions which are, in general, not applicable here. Calls to an attorney's office are privileged even if the attorney never got on the phone. Communication with the support staff can be just as damaging as communications with the attorney if revealed to the other side. The mere fact of an attorney's consultation or representation is confidential. Much of the time, the fact of representation will be publicly known - but occasionally it can be critically important that a client's consultation with counsel be kept secret. Having the government intercept and record ANY communication with counsel is extremely problematic. Jails and prisons have systems in place which are intended to ensure that phone calls to legal counsel are not recorded (the inmate or attorney notifies the staff that the call is privileged, and a different phone system or procedure is used). The revelation here is that those safeguards are apparently all for show, and they record and archive the calls anyways.

Comment Re:See the end of her blog post.... (Score 1) 928

Posting to undo accidental down-moderation. You have a great point, which I was trying to reward with an "insightful" mod. As a litigation attorney, I deal with nothing but high-stakes contentious situations. Most often, the people (both lawyers and litigants) who complain the most about their adversaries are actually the most unnecessarily aggressive and unpleasant participants. It seems to be a form of psychological projection. "You're totally unreasonable! You're acting in bad faith and obstructing the case! No we won't give you any documents, and we won't settle! We want sanctions, and we won't participate in mediation!"

Comment Re:Concorde didn't fail because of tech (Score 1) 221

It failed because the cost of tickets was unsustainable...

The Concorde failed because a tire exploded, it streaked terrifyingly across the Paris sky trailing hundreds of feet of fire, and crashed in a giant fireball, killing everyone. And then the fleet was instantly and irrevocably grounded. The program had its economic issues over the years, but was still in operation nonetheless - until the disaster.

Comment Re:yoda head makers (Score 1) 130

OOh so in your world, you can only be a real maker or a true scotsman if you work with metal or wood.

And why is that exactly? Is there another reason other than wanting to feel superior?

But in most cases you don't need a 3D printer that oozes soft plastic crap.

Most 3D printers will happily print ABS, which is one of the most commonly used plastics.

You can only be a "true maker" if you have the capability of working with a variety of materials to suit the needs of the part, just like you can only be a "true maker" if you have some ability to work with electronics, plumbing/hydraulics, and mechanics, and if you can make parts using a variety of different fabrication methods depending on what suits the conditions. Choosing appropriate materials is a critical part of making something. "Soft plastic crap" presumably refers to PVA, which is mechanically unsuitable for most applications. ABS is more usable, but still not a reasonable engineering material for a lot of uses. Wood isn't either. It's pretty fair to say that someone is not a "true maker" unless they can select between materials and fabrication methods that are reasonable for a variety of different engineering needs, and that necessarily includes subtractive manufacturing of metals - the #1 most common method of making strong mechanical parts.

Comment Re:And your favorite, hobby laser cutter is... (Score 2) 28

I have a £550 Ebay 50W laser which can cut 6mm acrylic well (though with bevelled edges currently - I'm hoping to be able to do something about this though with some better set up). I've done 6mm ply but it all came out rather burnt. Again, I'm hoping to do better once I find the ideal settings. Overall I've been impressed with what it can do for the price.

A compressed air jet can greatly improve performance on thick material. If your edge quality issues are a result of melting in the heat-affected zone, that would be a major improvement. If it's a beam diameter problem, then a longer focal length lens will help. It's also good to make sure your focal point is inside the workpiece, not on the surface, if you are seeing a wider kerf on the bottom than the top.

One picture is worth 128K words.