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Nukes and America’s Energy Future

Even if ground-based nuclear power was economically viable in the USA (which it it isn’t, despite massive subsidies) I don’t think our socio-economic system is set up to handle nuclear power. It seems unlikely to me that an adequate level of quality technical administration can be maintained in the post-Reagan business environment; our corporations will inevitably cut costs and staffing until an accident occurs. And that kind of feedback loop does not match up well with pollutants that have lethal doses measured in parts per million and half-life measured in thousands of years.

Fermentation products, particularly methane (aka “Natural Gas”) and alcohols from cellulose (currently not in large-scale production, but China’s already building out the infrastructure) are a far better choice than nuclear. We’ve already got the infrastructure and distribution media for it, and it’s infinitely sustainable and carbon-neutral. Scientifically, it’s a no-brainer; it even leads theoretically to future global temperature management schemes based on vegetative sequestration and release of carbon.

Nuclear power generation works great in space, and we should use it there. On earth we already have clean methane burning appliances available in the Home Depot and Sears, and we already have containment technology that works and restricts accidents to manageable proportions. The biggest real obstacle is that sustainable fuels displace profits from the currently dominant political and economic powers, namely the Texas Oil Barons and their dirty energy lobby. If you build a giant algae vat in Death Valley that generates clean methane or alcohol from waste agricultural products incredibly cheaply, you will directly take income from Esso and Texaco. If you build a nuke plant, there’s no problem, because the dirty energy lobby also owns the means of nuclear power plant construction and operation, and I’m sure they’d much prefer walled nuke plants patrolled by Erik Prince’s armed goons to huge empty plains spotted with oil derricks.

Antikythera mechanism on your wrist

Despite my well known obsession with the Antikythera device, I somehow didn’t notice Loz Blain’s excellent 2011 sildenafil samples Successful samples of generic viagra treatment: You always want a treatment that had been withered away for a long time. Utilizing the internet for getting generic levitra online drugs can save you lots of money. Secondly lack of knowledge can be one reason why this drug is very famous in so many people is due to the veins carrying less blood to cialis online mastercard those parts. Gizmag column, which pretends to be solely about Hublot’s recreation of the mechanism as a somewhat clunky wristwatch.


For my kids

Remember this the next time I almost burn down the property, OK?

SatNOGS wins Hackaday prize

Coverage here. Very impressive, but personally I was even more impressed by the DIY spectrometer.

Skunk works claims hot fusion breakthrough

Lockheed’s secret lab says they’ve solved the problem of hot fusion containment, and that they can build a 100 megawatt reactor small enough to fit on a truck in less than one year, with commercial prototypes in less than five years, and reactors available on the market in a decade.

Supposedly it took them only four years to work this out, which makes you think of Bussard’s talk to Google back in 2006, where he claimed that the only reason we didn’t have working fusion reactors was lack of will.

Hot fusion is a highly energetic, highly radioactive process but it does not generate extremely long-lived waste like conventional fission reactors do. A hot fusion reactor accident might do as much initial damage as a fission plant accident, but the long-term cleanup would be relatively simple; if we can’t have true cold fusion, hot fusion is still a big step up from coal or fission.

Armor gymnastics

https://www.youtube.com/watch?v=5hlIUrd7d1Q

Craptacular Eskimo Fan

Heather bought another old fan at the Arden Fair a few weeks back. It’s a single speed oscillating Eskimo with aluminum blades from the late 1930s. It has a somewhat attractive pseudo-Deco design with a spiderwebbish pattern to the cage.

Dissassembly revealed not only unbelievably thick crud deposits (half an inch of greasy fur inside the casing) but also the cheesiest design and materials I have ever seen in an antique fan.
EskimoFanOpen
The shaft bearings are thin and very yellow, very little copper content. But not all of the bearings are even metal! Some of them appear to be made of greased cardboard. The stator windings are literally bound with masking tape, although the wire nuts are porcelain. Two of the gears in the oscillator box are made of masonite – steam-pressed wood fiber. The worm gears they engage are steel, so don’t grab the fan and prevent it from oscillating unless you enjoy the sound of masonite gear teeth snapping off. The blade is soft aluminum, so soft that sticking a finger into the cage will almost certainly unbalance it… two of the blades are already bent, so that it vibrates noisily and the main shaft sidles erratically in and out like a trombone slide.

Even without the blade mounted it still sounds like a gravel crusher and the main shaft wobbles all over the place, because the squirrel cage rotor has never been balanced and all the cheesy bearing surfaces are worn out. If you push the oscillator shaft bearing up into the housing with a penknife it’ll swing back and forth wildly, at surprising speed, until the shaft bearing flys back out and the gearing disengages. I guess with a 2-pole stator and a 15-pole rotor you can’t expect smooth operation? The fact that the oscillator must have fallen apart almost immediately is probably what preserved those masonite gears.

Generous and repeated use of PB blaster, WD40, degreaser, and ultrasonics have given this piece of junk an interesting wabi-sabi patina that I kind of like, so I’m thinking about replacing all the bearing surfaces with bronze, and seeing if I can reshape the blade to restore balance. Planishing fan blades is always a big challenge, though.

Hawking radiation precludes singularity formation?

Laura Mersini-Houghton at the University of North Carolina and Harald Pfeiffer of the University of Toronto have published a paper suggesting that as a collapsing star emits Hawking radiation, it must also shed mass at a rate that would necessarily prevent it from achieving the density necessary to form a singularity. This doesn’t mean they are claiming black holes don’t exist, they’re saying that if Hawking radiation is real (and so far it’s entirely theoretical) a black hole singularity cannot be formed by the implosion of a star.

Of course if a mass is high enough to create an information paradox, would we ever be able to tell if that mass is a point singularity or not? I don’t know, but the non-mathematical parts of the paper are surprisingly readable.

2014 IgNobels awarded

Winners were ceremonially announced last night. I haven’t yet watched the awards video, so I do not know if Miss Sweetie-Poo was called into service.

The Medicine Prize was won by Ian Humphreys, Sonal Saraiya, Walter Belenky and James Dworkin, for developing a means of treating uncontrollable nosebleeds that involves packing the patient’s nose with bacon.

Haban Sickle-Mo

Example of a small sickle-bar type mower, and why they are great for stream edges, under fences or treelines, and alongside roads. You can keep to the safe ground and reach out to one side.

The bad thing about them is that they are pretty much giant scissors, so they are tough to sharpen, and just as dangerous to wildlife, kids and misplaced property as any other mowing system. I think snakes would argue that they are even more dangerous, because they are relatively quiet.

Building a spring-pole lathe

Master craftsman Peter Follansbee builds a sweet medieval-style lathe.

I’ve seen this done with a live, rooted sapling instead of the cut green pole Peter’s using.

Great blog posts on color perception

I was taught in school that when light of a certain frequency strikes your eyeball, you see it as a specific color. This is almost completely untrue.

Jason Cohen talks about the inadequacy of the color wheel.

Jason doesn’t mention it, but the part of your brain responsible for color vision is about the size of a lima bean. (You know these things if you read Oliver Sachs.)

Robert Kosara talks about how the practice of assigning R-O-Y-G-B-I-V values to map data misleads viewers.

Color is a cognitive effect, a subjective phenomenon of the mind, that is influenced by culture and language as well as by gross physical circumstances like lighting and surroundings. The influence goes both ways – not only is our vision mediated by our state of mind, but also vice-versa.

High Voltage Cable Inspector Guy

http://www.youtube.com/watch?v=9tzga6qAaBA

Brick vault construction with no supporting forms

Highly skilled mason Hugo Martinez demonstrates the construction of a catalan vault in Querétaro, Mexico. Eight hours of work compressed into 12 minutes, so you can see the full development of the pattern.



Time Domain Reflectometry visualized

Wikipedia provides this excellent graphic to help explain how you can determine where the fault is in a very long cable.

Reflection of an electric pulse back towards point of origin

Time delay reflectometry is a clever trick where you can calculate the location of an imperfection in a conductor by timing when the “bounce” returns, as long as you know the speed of signal propagation in the wire (which you generally do).

The impedance of the discontinuity can be determined from the amplitude of the reflected signal. The distance to the reflecting impedance can also be determined from the time that a pulse takes to return. The limitation of this method is the minimum system rise time. The total rise time consists of the combined rise time of the driving pulse and that of the oscilloscope that monitors the reflections.


Plumbers will note that the behaviour of the electric flow here is analogous to water hammer. I think it should be possible to find the distance to an obstruction in a pipe as a TDR calculation, as long as you know how compressible the fluid medium is.

Happy Apollo 11 Launch Day

It was a school day, but dad’s rocket was going to take men to the moon!

240 VAC hurts

When I was much younger, I worked one summer as an Electrician’s Mate in a munitions plant. I was hired (and paid) as unskilled labor – fetch and carry, hold the flashlight, etc. – but the electricians I worked with soon discovered I had a pretty strong familiarity with electricity, mostly thanks to my father. I was good at soldering, I knew P=IE and E=IR and I could calculate resistances in parallel, and all that put me in a different category from the other helpers. So before long I was helping to wire breaker boxes, replacing outlets, and so forth.

I should point out here that my senior co-workers were not exposing me to unnecessary dangers by allowing me to do the more complex jobs. Among the tasks normally expected of unskilled helpers was weeding inside the caged-off areas around extremely high-voltage sources, tens of kilovolts, where a misstep could easily mean an ugly death. And of course we are talking about a factory that existed to create dangerous items and situations in the first place… it was never supposed to be a place where a person could blunder around unthinkingly and expect to survive. Unlike most American workplaces, staff there were treated as fully self-actualized human beings, capable of making life and death decisions routinely without reference to rulebooks. So as an employee, you were not just expected but required to understand what you were doing and required to do it safely. Once I had I proved to persons in a position to make such a judgement that I could work with electricity without harming myself or others, they permitted me to do so.

But maybe I got a little too cocky, being the only guy without a journeyman’s rating that was allowed to work with very little supervision. And maybe I was a little too bold, willing to volunteer for tasks the older, family men weren’t so quick to take on.

Anyway, there’s a small valley in the woods behind the plant that’s full of magazines. Magazines are these little concrete and steel shacks, made of six pre-cast panels held together solely by gravity. They’re kept from falling down by big galvanized steel pins at the corners; a crane drops each of the four walls onto the base slab, then a slab roof is dropped on top. Deep-buried wires provide electricity to each magazine’s electric heater and an air conditioner, and one slab wall has a thick steel door in it.

If the extremely powerful explosives stored in a magazine blow up, the blast berm around the magazine directs the force of the expanding gasses upwards into the air, and afterwards you bring a crane down and pick up the surviving pieces of the magazine and put it back together again.

Aerial shot of a small group of magazines

Aerial shot of a small group of magazines


Magazines are kept at very specific humidity and temperature levels, so it was often necessary to run the heaters and air conditioners simultaneously on humid summer days. You had to condense the moisture out of the air with the AC unit, which meant you had to run the heater to maintain temperature. These things run unattended for years, sometimes for decades, so there’s remote monitoring and alarms go off whenever a piece of equipment malfunctions or the temperature begins to creep outside allowable limits. And on some sort of schedule, a watchman would visit and sample the humidity with a sling psychrometer (I’m sure they use electronic hygrometers these days).

It must have been about 90 degrees outside the day I volunteered to fix the air conditioning in one of the magazines. I can’t remember how it came about that the A/C service guys determined that a relatively skinny person was needed to wriggle into the blisteringly hot space just below the roof of the magazine and replace a bit of control wiring with a soldering iron. I do remember that when they called the electrician unit, they were in a big hurry, because the temperature and humidity were already rising precipitously. None of us knew exactly what was in the magazine, but everyone was vaguely half-expecting an earthshaking BOOM accompanied by shattering windows throughout the plant.

This is what I learned that day.

#1) Most air conditioning systems (other than American window units) run on 240 volts. I have no idea why I ever thought otherwise, nor do I know why nobody told me the control circuitry for these particular AC units was running full voltage. But I had grown pretty blase about 120 volts, and didn’t take a lot of precautions while I was sliding around in the dark by the light of a weller gun.

#2) Although perfectly pure water is an insulator, and dry human flesh is a poor conductor, a sweaty human will spasm like a click-beetle if given a good old-fashioned electric shock. When I accidentally touched a live 240 lead my sweat-soaked body conducted enough juice into my muscles that I got bruises all over my body, particularly on my knees, elbows and the back of my head, which slammed into the top of the magazine at least once. But you can’t scream (or think, really) when you’ve got that much current passing through you… and nobody can hear you thumping around from outside of a steel-reinforced concrete box six inches thick.

#3) A healthy teenager can survive brief contact with 50 amps of 240 volt alternating current. (Due to the thrashing mentioned in lesson #2, my contact was extremely brief.) And within fifteen minutes or so, said teenager will be sufficiently recovered to lie convincingly about the incident if asked why the job took so long.

My mother still doesn’t know this ever happened, so don’t tell her.

Wood of Life

Wikipedia and Google Translate both say that “Lignum vitae” is Latin for “tree of life”. Though no Latin scholar, I disagree; tree of life would be “Arbor vitae”. Lignum vitae is the lumber of life; lignum being the ancient Roman word for a beam or roof timber.

Confusingly, lignum vitae wood does not come from Thuja occidentalis, the arbor vitae tree. Instead it is harvested from small ironwood trees of the genus Guaiacum, which are native to the Caribbean and the northern coast of South America. Lignum vitae has been an important export crop to Europe since the beginning of the 16th century, so much so that it’s now an endangered species. The trees take three to four hundred years to mature, so it’s not particularly amenable to tree farming, especially given the long-term political instability of the regions where it is found.

Lignum vitae’s claim to lasting fame is a remarkable combination of strength, toughness, and density. The wood is so dense it sinks in water, and it’s so tough that it has been used for submerged bearings in hydro turbines in continuous operation for a hundred years. Yes, I said in continuous use as a bearing supporting a heavily loaded rotating shaft for a hundred years. Bearings made of lignum vitae were used for the rudders of great sailing ships, for the propellor shafts of steamships, for the main bearings of water-powered mills, for nearly anything you can imagine including wheelbarrows and snowblowers. Any place that bronze isn’t tough enough and steel is too likely to corrode, you’ll find a use for lignum vitae, and somebody’s probably used it. There’s just no other material like it – which is why the US Navy still uses it for jackshaft bearings in nuclear submarines, and it’s still used in huge modern hydroelectric plants. It’s been used for pulleys in steel mills, for British police batons, for cannon balls, and for gears in wooden clockworks. Only two woods have ever tested harder – South American Quebracho or “axe breaker” wood (Schinopsis spp.) and Australian Bull-Oak (Allocasuarina luehmannii) – neither of which have the workability or durability of lignum vitae.

DENSITY: 80 lbs./cu.ft.
SPECIFIC GRAVITY: 1.37
TANGENTIAL MOVEMENT: less than 1%
RADIAL MOVEMENT: less than 1%
VOLUMETRIC SHRINKAGE: less than 1%
JANKA HARDNESS: 4,500 lbf (20,000 N)
DURABILITY: Exceptional resistance to moisture, fungi and rot
DESCRIPTION: Reddish brown when freshly cut, with pale yellow sapwood. As it oxidizes, the color turns to a deep green, often with black details. The grain is highly interlocked, making it difficult to work with edge tools, but it machines well and takes a high polish.

But it’s not just these exceptional engineering properties that make lignum vitae marvelous.

The flowers, resin, bark, and wood chips of Guaiacum trees have dozens of medicinal uses, some traditional and unverified, others well-documented in modern medicine. The resin is used for coughs, arthritis, and is a traditional West Indies pick-me-up and reputed aphrodisiac. The modern expectorant guaifenesin, (which is also used by veterinary surgeons as a horse muscle relaxant) is derived from the wood. Cellini cites it as a treatment for syphilis. Teas made from the bark and flowers have spawned more folk medicine than ginseng, and guac cards are still used for fecal blood testing. As a food additive Guaiacum has the E number of E314 and is classified as an antioxidant (insert eye roll here). Oil of guaiac is used as a soap fragrance. The list of uses just goes on indefinitely!

There are a lot of names for the various species of guaiacum. It’s called “caltrop tree” because of the foot puncturing seeds of some varieties, and the Spaniards called it palo santo or “holy wood”. If you live in an area where it can survive, you’ll find it under various names in garden centers, where its sold for its muscled trunks and pretty blue flowers. Because yes, it’s not just amazingly useful, it’s also attractive – Guaiacum Officinale, the common or true guaiacum, is the Jamaican national flower, and Guaiacum sanctum is the national tree of the Bahamas.


Falcon 9 reusuable 1000m fin test video

This video’s got on-board cam and wide-angle shots of the entire flight. The landing gear catches on fire, which was apparently expected by SpaceX (later versions will fold up their landing tackle after liftoff) although a bit surprising for me at first viewing. This flight is to test a set of landing flaps they are calling “fins”.

Installing a Square D Electric car charger

Since we’ve got two electric vehicles and a plug-in hybrid, it seemed like time to install a level 2 charging station.

After spending about six months studying the options, we decided on the Square D Model EV230WS which periodically goes on sale at Amazon and the Big Box stores (where shopping is a baffling ordeal!) for about $600.

Honestly, I don’t know if it’s really appropriate to call things “Square D” any more. The company was bought out by (nominally French) multinational megacorp Schneider Electric in 1991, after which they introduced the “homeline” series of circuit breakers and load centers, which are not as well regarded as the industry-leading QO series. But on the other hand, Schneider does still make the QOs, and they are still an excellent product family – I put a big QO breaker box in my house when I upgraded the main service a few years back, and I am very satisfied with it.

The new charger is connected by 8 gauge copper wire with a NEMA 14-50 plug and receptacle, a Square D QO series safety switch, and a 40 amp breaker. The actual current draw of the charging station is 30 amps at 240 VAC, so I am still well within code for the 100 amp subpanel in the barn, and having the 14-50 plug means we can potentially support other 240 mobile loads like Teslas, large RVs, plasma cutters, and portable welders.

Now the plug-in Prius should charge in 1.5 hours instead of 3, and the Leaf is supposed to drop from a totally impractical 16 hours (on the level 1 charger) to much more user-friendly 5 hours.