Scumbag Dakota Access Pipeline Protesters

Today, Townhall ran the headline story that not only did the Dakota Access Pipeline protestors leave an amazing amount of waste behind, they abandoned dogs.

There's a special place in Hell for people who abuse animals - and it's often the first sign of someone who will transition to abusing humans. 

The environmentalists came to North Dakota to protest the construction of the Dakota Access Pipeline and lost. Now, as the cleanup of their protest camp begins, authorities have found it to be a disaster zone. There’s enough garbage and human waste to fill 2,500 pickup trucks. With the ending of the winter months approaching, they fear the spring flooding could wash this waste into the Missouri River, polluting it and other waterways. Yet, efforts to prevent an environmental disaster before the spring have hit another obstacle. Besides leaving heaps of garbage, protesters have left their pets.

After they found the first few dogs, cleanup efforts were halted and a rescue organization came in to search for more abandoned pets. 

Two dogs and six puppies were found and rescued at the main Dakota Access Pipeline Camp by Furry Friends Rockin Rescue.

The rescue has been working hard to catch ALL the animals that were left behind at the camp, but Furry Friends Rockin Rescue isn't giving up on these abandoned pets.

Furry Friends reports that the sound of the heavy construction equipment being used to clean up after the protesters is scaring the dogs and they're hard to find.   There are still protesters in the camp, all subject to arrest, but the majority have left.  The state of North Dakota offered protesters a sweetheart deal including health checkups, hygiene kits, meals, and bus tickets out of state.  One report I heard last week said protesters were being offered a ceremonial arrest if they wanted a picture to post to Facebook or other ego booster.  In my mind, the state bent over backwards to be kinder to the protesters than they deserve. It's only encouraging the bad behavior. 

MORE UPDATED INFO from North Dakota Joint Information Center:

Travel Assistance Center Established for Protesters

Bismarck, N.D. – The North Dakota Department of Human Services, North Dakota Department of Emergency Services and the North Dakota Department of Health have partnered to set up a travel assistance center. This free service will provide protesters with support as they prepare for their return home.

The transportation assistance center will offer personal kits, water and snacks, health/wellness assessments, bus fare for a return trip home, a food voucher, hotel lodging for one night, and a taxi voucher to the bus terminal.

Transportation will be provided from the protest camp to the assistance center.

All camp residents are encouraged to take advantage of these amenities.

Travel Assistance Center Flyer

Greetings,

If you don’t have means to return home, you can receive a ride to the Travel Assistance Center in Bismarck, where you will receive:
· Free health and wellness check-up
· Personal hygiene kit
· Voucher for a one-night stay at a designated hotel in Bismarck
· One $15 meal voucher for Kroll’s Diner in north Bismarck
· Ride voucher from the hotel to the Bismarck Bus Depot the next morning.
· Jefferson Lines bus ticket (Good for non-local destination. Must be in the lower 48 states.)
After you receive your supplies, you will be given a ride from the Travel Assistance Center to the designated hotel.

NOTE: No pets will be allowed.

I don't think that's why those dogs were abandoned.

(Photo from Townhall)

On Cellphones, Radios, Motors and Waterproofing

A few years ago, I posted a story about having one of those bad days that ends up costing a lot of money.   To shorten the story somewhat, while returning to dock, I got into one of those "America's stupidest home video" moments - feet on the deck while stretching out to reach for a piling - and fell out of the boat into the saltwater lagoon.  There's only one positive thing I can say: I didn't get hurt.  I can't say the same for the iPhone 4s in my pocket, which never worked again, and had to be replaced.

If you go out to buy a waterproof phone, radio, or any other item, you're going to run into two kinds of salesmen.  One will say, "sure it's waterproof".  The other will say something like "It's rated to IPX67", or "it can be submerged in a puddle or a few feet of water for half an hour".  Avoid the first salesman.

Industrially, people are very reluctant to say waterproof because they want a definition to test their products to.   For example, consider the term waterproof camera.  It means something different to someone going out on a boat and wants to make sure their phone's camera will work if it gets hit by water drops than it does to someone who wants to go SCUBA diving in 60 feet of water. 

The manufacturing world has largely gone over to IP codes: the International Protection Marking, IEC standard 60529, sometimes interpreted as Ingress Protection Marking.  On a product, the codes are denoted by the letters IP and two digits.  The first denotes being sealed against solids or particles, and the second denotes being sealed against liquids.   The first digit can run from 0 to 6 and literally runs from entry of something larger than a hand down to dust particles:

Level sized	Effective against	Description
0	—	No protection against contact and ingress of objects
1	>50 mm	Any large surface of the body, such as the back of a hand, but no protection against deliberate contact with a body part
2	>12.5 mm	Fingers or similar objects
3	>2.5 mm	Tools, thick wires, etc.
4	>1 mm	Most wires, slender screws, large ants etc.
5	Dust protected	Ingress of dust is not entirely prevented, but it must not enter in sufficient quantity to interfere with the satisfactory operation of the equipment.
6	Dust tight	No ingress of dust; complete protection against contact (dust tight). A vacuum must be applied. Test duration of up to 8 hours based on air flow.

The second digit can run from 0 to 9 with a special suffix:

Level	Protection against	Effective against
0	None	—
1	Dripping water	Dripping water (vertically falling drops) shall have no harmful effect on the specimen when mounted in an upright position onto a turntable and rotated at 1 RPM.
2	Dripping water when tilted at 15°	Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle of 15° from its normal position. A total of four positions are tested within two axes.
3	Spraying water	Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect, utilizing either: a) an oscillating fixture, or b) A spray nozzle with a counterbalanced shield. Test a) is conducted for 5 minutes, then repeated with the specimen rotated horizontally by 90° for the second 5-minute test. Test b) is conducted (with shield in place) for 5 minutes minimum.
4	Splashing of water	Water splashing against the enclosure from any direction shall have no harmful effect, utilizing either: a) an oscillating fixture, or b) A spray nozzle with no shield. Test a) is conducted for 10 minutes. Test b) is conducted (without shield) for 5 minutes minimum.
5	Water jets	Water projected by a nozzle (6.3 mm) against enclosure from any direction shall have no harmful effects.
6	Powerful water jets	Water projected in powerful jets (12.5 mm nozzle) against the enclosure from any direction shall have no harmful effects.
6K	Powerful water jets with increased pressure	Water projected in powerful jets (6.3 mm nozzle) against the enclosure from any direction, under elevated pressure, shall have no harmful effects. Found in DIN 40050, and not IEC 60529.
7	Immersion, up to 1 m depth	Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time (up to 1 m of submersion).
8	Immersion, 1 m or more depth	The equipment is suitable for continuous immersion in water under conditions which shall be specified by the manufacturer. However, with certain types of equipment, it can mean that water can enter but only in such a manner that it produces no harmful effects. The test depth and/or duration is expected to be greater than the requirements for IPx7, and other environmental effects may be added, such as temperature cycling before immersion.
9K	Powerful high temperature water jets	Protected against close-range high pressure, high temperature spray downs. Smaller specimens rotate slowly on a turntable, from 4 specific angles. Larger specimens are mounted upright, no turntable required, and are tested freehand for at least 3 minutes at distance of 0.15–0.2 m. There are specific requirements for the nozzle used for the testing. This test is identified as IPx9 in IEC 60529.

As you can see it's rather specific in what it says the product is protected against, and there's an additional column that I omitted which talks about how these things are tested!

As I alluded to above, many VHF radios are rated to IP67, sometimes called IPX7.  There's no rating for dust because it's assumed that anything sealed against water is going to be sealed against dust and particles as well.  I've seen ads for smartphones that imply a certain level of waterproofness, the commercial showed them being washed in soap and water, but no IP ratings on them.

A practical application of this subject that's important to me right now is waterproof stepper motors.  Mine aren't.  In my last couple of years at work, I got involved with evaluation and testing of stepper motors (the radar antennas were moved by stepper motors) which were rated to be extremely resistant to water spray and corrosion.  For this to work, the motors had to designed to meet tough specifications from the start.  It wasn't possible to take a standard part and just dip it some sort of coating.  The motors were rated to MIL-STD-202G, a salt spray test with varying test times.  Their motors looked better at 10 days than the competition at 2 days and survived all of our tests without missing a step. 

There are hobby-level motor suppliers who will apply some sort of brushed on or dipped coating over much of the motor for a fee.  They can't seal where the motor shaft comes out of  the body or it won't turn.  Based on how such coatings performed on our aviation radars, I'd say it's not worth bothering to get this.  Squirt some RTV around where the wires leave the body of the motor to seal it, and realize it's about as good as you're going to get.  The motors aren't intended to be submerged (IP67 or X7), but the experience of many people seems to indicate that they can handle some splashing. 

To complicate things, there are other standards, like the older NEMA (National Electronics Manufacturing Association) ratings.  NEMA 6 looks like it would be a worthwhile level to try for, if a NEMA rating is all you have.

I Don't Get the Whole "Repeal and Replace" Bit

My version goes like this.  Picture your doctor telling you that you have a tumor that's destroying your {insert organ name here}.  Then he tells you the treatment is to remove it and replace with a different tumor.  Who wouldn't say "WTF???" to that?

Why should we want to replace it?  Why wouldn't we just want to burn it to the ground and do everything we can to create a free market in medical care?   From what I can see, the problem with healthcare is over regulation and a thoroughly broken market because of it.  This brokenness has been building for over a hundred years.  Naturally, anything that took a hundred years to break is going to be hard to unscrew. 

(Michael P. Ramirez cartoons). It's going to feel this slow no matter what, but the Stupid Party pulled a major stupid by passing House bills to end Obamacare over 40 times, but not bothering to have a backup plan ready to drop in place.  It's not like they haven't known since November 8th that Trump was going to be president and this was high priority.  Obamacare wasn't written after he was inaugurated, it was written in advance; parts of it years in advance.  It was deliberately and strategically made hard to repeal. 

The stunning reminder to me of how fubar everything is was in a short story about California Senator Kamala Harris on the Blaze.  There have been reports that the coming reform cuts federal payments for Medicaid.  It boils down to this astounding statement.

But according to Harris, the Medicaid rollback would be detrimental to Californians because “1 in 2 Californian children depend on Medicaid,” the junior California senator tweeted Friday.

Half of the children in California are on Medicaid?  Half?!?  I don't think you could find a bigger indictment of California or of Democratic policies than that.  Unlike Harris, I don't define success as having half the population on welfare.  Success is getting them off welfare. Something needs to be done for those children, but is the solution to enlarge the welfare state or direct efforts to getting them out of poverty? 

Few people alive today have any memory of a working healthcare market; even fewer than the number of people who can envision a world without constant inflation.  There was a great interview last week, on Tucker Carlson's show in which the guest, Steven Weissman, former president of Palm Springs hospital in Hialeah, Florida, was making this point about the market being broken and nobody being able to know the prices for procedures or tests.  Go watch that video. 

Not Going as Smoothly As Hoped

I've been working on the enclosure for my mill since the post last Saturday, and it isn't exactly going effortlessly.  Smooth isn't a word that I'd use.  I spent a lot of time verifying dimensions and then cut the aluminum extrusion to length, then cut all the opaque plastic panels.  Finally, I cut the two wider transparent panels so that I could build the side panels.  These seemed like an easy place to start. 

I have the two side panels built.  These are one opaque and one transparent panel in a frame with a divider between them.  The rendering looks like this

The way I tried to build these was to build the top and bottom rails first.  These are 35" pieces of the 15mm extrusion this is built from.  They get stamped steel L brackets which require four M3 5mm screws and M3 nuts, and I mounted the L brackets that go in the ends, tightening only the two screws that anchor the bracket to the top or bottom rails.  I left the bracket in the middle loose until I got the plastic panels in the right places.  I put a few (~2 to 4) extra nuts in each segment in case I want to add something at a later date.  The L brackets attach the three uprights to the top and bottom rails.  It might be better at this point to show you a finished panel so that maybe you can see these details. 

The main difficulty is that the white corrugated plastic (Coroplast) is 4mm thick nominal, while the groove in the extrusion is 3mm wide.  The "all you gotta do" answer is to slit the ends of the corrugations and the length of the sides, and then it slides together easily.  Not quite.  My idea was to slide the white plastic panel into the slot in the extrusion along the right vertical piece, into the groove in the bottom and then slide the middle upright onto the panel.  That was troublesome.  Because the plastic is being compressed into place, it works better if you slide the extrusion along the edge of the Coroplast, except that it gets a bit harder to slide it every inch as the friction increases.  Getting the entire edge in place at once turns out to be essentially impossible, but with patience, pressure, and small jeweler's screwdriver to help center the panel, it can be forced into the groove all the way around.  Once the white half was made, I slid the acrylic into the left side, and that was enormously easier.  It's 2mm thick in a 3mm slot.  Even with the corrugations slit to make the Coroplast more compressible, it's rough to get in the slot. 

The second one took a bit less time, but was still rough to do.  I did most of it with the pieces lying horizontally on a convenient flat surface (our freezer) and alternated between that and standing it on edge on the floor.  Mrs. Graybeard was a great help and did  a lot of the fussy details of assembly.  In places where my height and strength advantage would help, I took over.  

The back panel is going to be rough without building some sort of fixture to help assembly, or some other changes.  The most direct would be to widen that 3mm slot so that the 4mm plastic fits into it more easily.  I haven't worked out just how to do it on any machine, but I have a 3/16" end mill, which would make the slot 4.76 mm wide.  Widening the slot would make assembly much easier. 

So What's a Good Chronograph?

Another info bleg post. 

I need a Chrono.  I've reloaded a few times, but never measured velocities on what I loaded.  That's like missing half (or more) of what reloading is all about. 

I've done some reading and with the typical chronographs, like the one shown below, a very common complaint is that they can be erratic in some situations.  The white plastic pieces are to diffuse the daylight and provide even illumination.  Passing clouds seem to bother them.  They won't work indoors without adding LEDs to provide the backlight because indoor lights flicker with the AC power line. 

Typical chronograph, a Caldwell G1.  I"d need to add a tripod, and I'm not sure this model has the features that I'd like. 

Caldwell seems to have come up with a solid idea for improving their Chrono by turning it upside down.   They're said to be usable indoors without extra purchases, but the tripod that's included is widely reported to not be very stable, and if there's one thing I can count on is wind.  Wind and passing clouds are very common around here.

It's a feature rich design, but will be over 2x the price of something like the previous model.  More if I need to replace the tripod (probably need to).

I will need to be able to set it up and have it not fall down.  I'd like to be able to control it and get readings from it remotely;  whether that's by wires or by wireless is a "don't care".  I'd really like it to be as solid in performance with passing clouds and the bright, hostile sun, as can be.  Indoor use is low priority, since my club is all outdoors, and I pay enough there that I have little incentive to go to indoor ranges.

Any Florida reloaders care to comment on what a good chronograph is?  Anyone? 

That Old Revolving Door Still Be Revolving

Meet Mary Jo White.

As that web page points out, Mary Jo White is the chairman of the Securities and Exchange Commission, appointed in 2013 by Barack Obama.  Actually, "was the chairman" is the proper tense because she left the agency upon Trump's inauguration and is now headed back to where she came from before she headed the SEC, the law firm of Debevoise & Plimpton, the New York-based law firm whose litigation department she previously headed.

“I got a call at 12:01 on Jan. 20, asking me to rejoin the firm,” said Ms. White, whose departure from the S.E.C. took effect that day. “And since I had a speech in San Diego, I used that time on planes to decide whether I wanted to practice law again.”

(12:01?  AM, I presume?)  You see, Ms. White's job at Debevoise & Plimpton was defending companies from the Securities and Exchange Commission.   She went from defending corporations against the SEC to regulating and policing corporations at the SEC, and is now going back to defending those corporations from the SEC again.

Wall Street on Parade puts it this way:

The news is also highly significant because it will mark the fourth time in four decades that Mary Jo White has spun through the revolving doors of Debevoise & Plimpton (where she represented serial law violators) to government service (prosecuting serial law violators). 

If you're feeling dizzy, that's why it's called the revolving door.

The New York Times adds this little tidbit.

One of her chief lieutenants in that effort, Andrew J. Ceresney, also rejoined Debevoise after serving with her as director of the S.E.C.’s division of enforcement.

I wonder if young Mr. Ceresney will be her successor in revolving the door between the SEC and Debevoise & Plimpton?  It's like the revolving door between the fed.gov and Goldman Sachs that led to them being referred to as Government Sachs.  

For his part, President Trump has nominated Jay Clayton, a Wall Street lawyer from the firm Sullivan & Cromwell, to replace White.  Clayton, who has not had his confirmation hearing, is expected to push for less regulations easing the burden on IPOs and the disclosures involved.

He has already laid out a capital formation agenda to Trump surrogates who interviewed him, a source familiar with the process said. And he has expressed interest in tackling some regulations involving accounting and compliance procedures that financial industry players say get in the way of deals and initial public offerings.

The firm of Sullivan & Cromwell has defended some of the big (TBTF) banks but I don't see allegations he was involved personally.  It appears he has less of the cozy relationships than Mary Jo White with Debevoise & Plimpton, and less than the Government Sachs Employment Complex. 

Some Numbers on the European Radioactive Iodine Story

An interesting little story popped up this week about radiation being detected across Europe, spreading from Norway to Spain.  In a way, it's as strong a click bait headline as anything they could put up, but there are some interesting details about this.  The US dispatched a specially modified aircraft, called a WC-135 to the area.  Think of it as a KC-135 (Boeing 707) modified to sample and monitor for radiation.

An interesting part of this story is that the isotope being reported is Iodine 131 which has the rather short half-life of  8.04 days (.04 days is just under 1 hour).  That means the release of this material has to have been rather recent.  It was reported by the French nuclear agency (ISRN) on February 13th that it was first detected six weeks prior to that.

Iodine-131 (131I), a radionuclide of anthropogenic origin, has recently been detected in tiny amounts in the ground-level atmosphere in Europe. The preliminary report states it was first found during week 2 of January 2017 in northern Norway. Iodine-131 was also detected in Finland, Poland, Czech Republic, Germany, France and Spain, until the end of January.

Anthropogenic, of course, means that it's typically only created by human efforts.  Certainly, it could have come from a fission bomb, but there are global networks to detect nuclear tests and they don't report anything suspicious.  Where else does it come from?  It turns out that this isotope is routinely produced for medical testing.  Could it be a lab accident?  

Let's ignore that for a moment and talk numbers.  The ISRN report says

In France, particulate 131I reached 0.31 µBq/m3 and thus the total (gaseous + particulate fractions) can be estimated at about 1.5 µBq/m3. These levels raise no health concerns.

What's a µBq/m3?  It gets a bit dense with details for a bit here, so I'm going to lift most of this explanation  from PJ Media's Charlie Martin.  That abbreviation represents a rate, and means 1 micro (millionth of) 1 Bequerel per cubic meter.  A Bequerel is a measure of how much radioactive material there is. 1 Bq means that one atom is decaying every second.  Saying 1.5 micro Bequerel implies one millionth of one atom is decaying but that just can't happen; atomic decay only applies to whole atoms.  To turn that into a whole number, you have to multiply the whole thing by 2 million, which says 3 atoms are decaying in 2 million cubic meters per second.

Two million cubic meters is a big volume, but does it help you visualize it better if I say 3 atoms are decaying in 70.63 million cubic feet?  Does it help if I convert that to 528 million gallons?  Neither of those help me visualize this large number, but Charlie Martin used an interesting example.  Remember seeing the picture of a German airship called the Hindenberg?  It had a volume of 200,000 cubic meters.   That's convenient because it means 10 of these Zeppelins would have 3 atoms of Iodine 131 decaying. 

Perhaps that's not a convenient visualization.  I find a lot of people have heard of the Banana Equivalent Dose (BED), an indication of the amount of radioactivity contained in a typical banana.  There's a little unit shuffling here (we're not talking cubic meters, after all), but it turns out that a BED is 15 Bequerels, or five times as much radioactive decay as in 10 Hindenbergs. 

The French ISRN stated almost immediately the levels were so low that this 131I is not a risk to health, and we see it's about equal to eating 1/5 of a banana.  Those agree since we know bananas aren't dangerous, except possibly calorically, if you have 27 bananas in one pie all in one sitting. 

The question, then, is still "where did it come from?"  131I is actually an important medical isotope, used for treatment mainly of thyroid disease -- thyroid cancer or Grave's disease. When it's used, the patient basically eliminates it through urine, and yes, the urine has to be treated as low-level radioactive waste, but inevitably a little bit escapes, especially places where maybe they aren't quite as careful as in the United States. Then it gets into the atmosphere, possibly from spray treatments of sewage, or something that creates an aerosol. 

It almost certainly wasn't from a nuclear weapons test, and there's a good discussion of why here.  In short form, other signs would have been detected. 

The most likely scenario, then, is  that some patients were given 131I for a thyroid disease, and went home.  Within a few hours, they urinated most of it into the sewer system, where some of it seems to have been discharged into the environment.  Maybe something malfunctioned at the sewage facility.  The radioactive decay will be gone within a couple of months (8 half lives would be 64 days) but was never a health hazard.  The only reason we know about it is that we can detect radiation at such absurdly low levels.

Clues From Deep in the Earth Found in Ancient Pottery

In what appears to be a neat example of detective work, activity in the Earth's magnetic field has been measured with unprecedented accuracy in time, by measuring magnetic particles embedded in nearly 3000 year old pottery.  The paper appears in the Proceedings of the National Academy of Sciences, often known as PNAS, from a team of researchers the majority of whom are at Tel Aviv University in Israel.  A friend sent me this link from NPR, although the story has been picked up fairly widely.

About 3,000 years ago, a potter near Jerusalem made a big jar. It was meant to hold olive oil or wine or something else valuable enough to send to the king as a tax payment. The jar's handles were stamped with a royal seal, and the pot went into the kiln.

Over the next 600 years, despite wars destructive enough to raze cities, potters in the area kept making ceramic tax jars, each one stamped with whatever seal represented the ruler du jour.

So what do ceramic tax jars have to do with knowing the magnetic field?

All those years ago, as potters continued to throw clay, the molten iron that was rotating [in the core] deep below them tugged at tiny bits of magnetic minerals embedded in the potters' clay. As the jars were heated in the kiln and then subsequently cooled, those minerals swiveled and froze into place like tiny compasses, responding to the direction and strength of the Earth's magnetic field at that very moment.  [text added - SiG]
...
Political instability provided another handy recording, because the royal seals stamped onto the jars changed often enough to allow the researchers to narrow down the timing of those magnetic records to windows of about 30 years.

"Instability — or even better, wars and destruction — are the best for us," says Ben-Yosef. (Peaceful transitions are nearly impossible to spot in sedimentary layers, but something like a burned city makes a clearly visible dark line. And the Assyrians had a knack for destroying cities.)

Interesting results come from this research.  To begin with, it correlates with other measurements, since the invention of the magnetometer by the great Carl Friedrich Gauss in 1832, showing that the magnetic field is getting weaker.  The usual estimate is that the field is 10% weaker today than "normal", but this research shows that fluctuations over fairly short periods were seen 3000 years ago.  

When Ben-Yosef and his colleagues studied 67 jar handles spanning from the late 8th century B.C. to the late 2nd century B.C., they found that the Earth's magnetic activity has been a lot choppier than people expected.

For example, the jars indicate that in the late 8th century B.C., the core went a little crazy. The intensity of the magnetic field spiked to about double what it is today.

"It was the strongest it's been, at least in the last 100,000 years, but maybe ever. We call this phenomenon the Iron Age spike," Ben-Yosef says.

Then, it weakened quickly after 732 B.C.E., losing about 30 percent of its intensity in just 30 years.

Importantly, the spike in magnetic activity has been verified elsewhere.  Geologist Steven Forman of Baylor University has also found evidence of a magnetic spike about 3,000 years ago, based on his study of Hall's Cave in Texas.  In Forman's work, though, there were no handy dates stamped on things, and his estimate of "3000 years ago" is less precise than the paper in PNAS.  They probably measure the same event, but without precise measurements in Texas, or some other scale, I don't know how they'd know.

As I wrote last August,

All of our lives, most of us have heard that the Earth is "due" for a North-South magnetic pole reversal with the experts saying the poles have flipped many times and it has been too long since the last flip.  The story I recall hearing was that it took a long time to happen; more like centuries than decades, and certainly outside typical lifespans.  Nowadays, there seems to be some belief that it could happen very quickly; on human timescales.

It's a bit of our gallows humor, but Mrs. Graybeard and I regularly joke that at our ages any membership could be a lifetime membership and any subscription could be a lifetime subscription, so when I see an article saying the poles could reverse "within our lifetimes", I'd like them to be a bit more precise.   Still, it could well be that the process has already started, and might even have been going on throughout our entire lifetimes.  Earth will probably go through a period of magnetic chaos before the poles reach their (more or less) permanent positions and that could well be within the life of people reading this blog.  It's possible there could be more than one of each pole for some time so that a compass would point to two different "norths", making navigation by compass impossible.  Birds and other critters that use magnetic particles in their bodies for navigation will have a hard time, and migratory patterns would be seriously disrupted.

For one view, I'll go back to the original article.

It's counterintuitive, but massive fluctuations like the Iron Age spike, Ben-Yosef says, indicate there's nothing to worry about when it comes to today's weakening magnetic fields. Fluctuation, he says, must be the norm for our planet's magnetic field, not a harbinger of apocalypse.

For counterpoint, I'll slightly modify what I wrote last August

No one alive has ever seen this happen, so everything they think they know comes from looking at old rocks and computer models.  None of these are verified by comparison to an actual, witnessed event.  Whether the TEOTWAKI situations that you'll read about would really happen or not is just as hard to say.  There don't appear to be mass extinctions associated with previous reversals, so it appears life muddled on through somehow.   A technological civilization might require more than just "muddling on somehow", though.  

I'm hoping that with a weakened geomagnetic field, auroras may become visible farther south.  I seriously want to see auroras some day.

 

A jar handle bearing the tax stamp of one of the ancient kingdoms (photo from NPR - image courtesy of Oded Lipschits).  

A Little Diversionary Swing

In double four time.

I've often thought that the big musical instrument manufacturers may make musical instruments, but what they sell are dreams.  I've written sparingly here about my own dive back into guitar, the resumption of an interest interrupted for 20 years.  When I started again in 2010, it had been longer since I played than all the time that I played put together.  While I'm sure I know much more of what I'm doing, the realistic fact is that everyone in my age group is faced with declining abilities in the pure physical aspects of playing, and guitar is an instrument with a lot of physical requirements.  Any of the musicians of our youth will tell you that.  This simply not the time in life to look for new speed and flexibility, although that's no reason not to try.

The companies find themselves in the position of marketing to the dreams of younger players; 20-somethings or teens who have the hunger to play for other people and the drive to ... perhaps ... make something of a mark in that business.  On the other hand, guitar makers sell the most expensive models in their lines to people who play as a hobby, all sorts of professionals who work a daytime job and are doing alright; they just maybe get together with friends once a week.  I'd bet they sell hundreds of "entry level" guitars for every top end model.

What prompts this is an emailed article that I got from Fender.  As an owner of a couple of low end Fender products, they regularly try to tempt me with more.  Today it was centered on one of my favorite musicians, Mark Knopfler, and Dire Straits great first hit, "Sultans of Swing".  Specifically that what made Sultans into the monster song it became was their Stratocaster guitar.

The fingerstyle master originally wrote it on a National Steel guitar in an open tuning, he once explained to Guitar World.

“I thought it was dull, but as soon as I bought my first Strat in 1977, the whole thing changed, though the lyrics remained the same,” he said. “It just came alive as soon as I played it on that ’61 Strat—which remained my main guitar for many years and was basically the only thing I played on the first album—and the new chord changes just presented themselves and fell into place.”

“Sultans of Swing” was initially recorded as a demo in 1977 and soon got some play at BBC Radio. A bidding war amongst record labels ensued, and Dire Straits signed a deal with Phonogram Records, who had them re-record it for their eponymous debut 1978 debut album. “Sultans of Swing” was officially released internationally as a single in January of 1979.

Of course, they're trying to imply that if you, yes you, get a Strat and work hard at it, you can sound like Mark Knopfler.  Chances are, you can't.  But there is a real chance there's some kid out there who is rabidly playing all evening instead of doing his homework that might be "the next Mark Knopfler".  As Mark Knopfler himself said in a BBC interview I saw (but can't remember enough to give you a link) that before Mark Knopfler became Mark Knopfler there were "lots of nights falling asleep with the guitar on my lap".

So now that I've whet your appetite for the real thing, while not the "album version", going almost 11 minutes vs. not quite six, they call this the most famous of the live performances captured on video.



This video has a mere 86 Million views on YouTube. 

Enjoy.

Bill Gates: Tax the Robots

A quiet little story that ran across the headlines this weekend is Bill Gates saying that robots that take humans' jobs should be taxed.

Right now, the human worker who does, say, $50,000 worth of work in a factory, that income is taxed and you get income tax, social security tax, all those things. If a robot comes in to do the same thing, you’d think that we’d tax the robot at a similar level.

And what the world wants is to take this opportunity to make all the goods and services we have today, and free up labor, let us do a better job of reaching out to the elderly, having smaller class sizes, helping kids with special needs. You know, all of those are things where human empathy and understanding are still very, very unique. And we still deal with an immense shortage of people to help out there.

Now Gates, bless his heart, seems not to understand that social security tax isn't supposed to be part of the general revenue stream (not that congress seems to understand that either), but the idea seems to be a bit of "outside the box" thinking about how we get from where we are to the Star Trek future.  It's rather big-government in its thrust, in the sense that he recognizes it's not really the purview of corporations to worry about the societal disruption of replacing employees with machines. 

A fundamental principle of sane economics is that if you want less of something, you tax it; hence we tax cigarettes, liquor, and people working for a living.  (Wait.. whut?)  Technology has been advancing at an increasing rate all of my life, and now fairly sane people are saying that robots will be taking over just about all jobs in the next 25 years or so.  Raising taxes on robots would undoubtedly dramatically slow down that shift, if not completely shut it down.  Gates doesn't give a mechanism, such as whether it would be a one time tax at purchase or somehow structured to look more like income tax.  Since robots don't earn income (one of the reasons they're attractive), there's no income to tax.  The only income would be a marginal increase in profits the companies might get, if any.  Is he suggesting a corporate tax?  Corporations don't pay tax: they add it to overhead portion of the price they charge.  That's something he should know.

To his credit, Gates seems to be aware that taxing robots would be a disincentive to the expansion of robotics.   

“You ought to be willing to raise the tax level and even slow down the speed” of automation, Gates argues. That’s because the technology and business cases for replacing humans in a wide range of jobs are arriving simultaneously, and it’s important to be able to manage that displacement. “You cross the threshold of job replacement of certain activities all sort of at once,” Gates says, citing warehouse work and driving as some of the job categories that in the next 20 years will have robots doing them.  [Bold added - SiG]

We could get into a reasonable discussion of just what a robot is. For example, I think of my CNC machines as robots in the sense that I program them to do things I might be doing manually, and CNC machining centers have been the mainstay of production machine shops for decades.  They aren't robots in the cute anthropomorphic sense, like we see in the movies or on TV.  It begs the question of what Gates wants to tax.  Pick and place machines that have been building electronics assemblies for 30 years?  The robots car manufacturers have been using since, oh, forever?  What about household appliances, like a washing machine or dishwasher?  There used to be people in society who did laundry by hand, and they were replaced by the home washing machine. 

As I wrote in December, the historical trend of robots vs. employment isn't what most people think.  In general, the number of jobs has gone up with the number of robots, not gone down.  In general, more automation has been a good thing.  My perspective on the much-cited idea that robots will soon be doing everything is that if the math doesn't work, it's not going to happen.  Gates seems to be forcing the world to comply with what he thinks it ought to look like, and I don't think it will work. 

(Asa Mathat at Recode)

Surprisingly Involved

I've spent pretty much all of yesterday and today modeling the enclosure for my CNC mill in my 3D CAD program, Rhino3D.  There was other work interspersed with it, but not as much as I'd like.

The problem is that the design isn't really documented on the DVD I bought.  There are glimpses here and there and some descriptions, but most of the information is spread between online forums and YouTube videos.  I got the material list from one of the forums and bought the hardware, but other than some rough guidelines, didn't have dimensions to cut anything to.  So it came down to drawing it up and counting hardware.  (There are things in this image besides the mill and enclosure.  It's just like leaving stuff lying on the floor in real life.)

I had the drawing for the wooden chip tray that has been shown here before, and was able to get a CAD model for the extrusion from the place I bought it, Misumi.  After that, it was a lot of calculator work, and design on the fly.

Then it was time to try to find sources for things like the plastic panels.  When I found I couldn't get the corrugated plastic I wanted for the original design with three panels, I changed it over to four panels today. The back panels and two of the side panels, seen in yellow here, will be white plastic.  The smokey/translucent panels will be clear plexiglass.  The four panels on the front are hinged on the ends and in the first seams, which are doubles of the extrusion.  The double extrusion in the middle is where the doors open and close. 

There's still lots to figure out, probably as I'm building it.  The upper rim of the back and sides will have some LED strip lights like these to get some light into the work area.  It's not very well lit in that corner of the shop, so the more light the better.  I'm not quite sure how to hook that up, either, if I want to be able to disconnect them to take off a side panel or something. 

Oh, yeah.  I hear the president was in town today.  Missed seeing or hearing Air Force One, and if I had been sitting in line all day, this would be very different. We were outside waiting for the SpaceX launch when they scrubbed.

Consumer Safety Groups Start to Look at 3D Printers

Ran across an interesting little piece on the user forums for Rhino3D, a link to a story in the American Chemical Society Journal Environmental Science & Technology which looked at emissions from desktop 3D printers.  The story on the Rhino forums was linked by Facto Design.

Anyone who uses a 3-D printer at work or home knows the tell-tale scent of the machine at work, a slightly burnt chemical odor that fades over time. If you're like me, you've long wondered whether you should worry about it. Now, a team of scientists from have published a study proving that yes—there are hazards in 3-D printing in enclosed spaces, especially with certain materials. But there are ways to mitigate it, so don't panic.

The author on this one is a bit over the top to me; I can't say that whenever I smell something like " a slightly burnt chemical odor" that I wonder if I should be worrying, but I know there are folks like that.

3D printing is a vast subject and even low cost, home-market printers print in a few different materials.  The article looks at a few of them.  Of most concern is whether the vapors emitted, the Volatile Organic Compounds (VOC), or the ultra-fine particles (UFP) they emit are potentially toxic or carcinogenic.  The most common material appears to be PLA, and it got the best results.

What they found was that the level of harmful particles and fumes depended mostly on the filament material, not the maker of the printer. For example, ABS emitted styrene, a type of chemical that's toxic and carcinogenic. Other materials based on nylon emitted caprolactam, a chemical linked to a laundry list of health problems. Meanwhile, the PLA filament emitted lactide, which is actually pretty benign. All told, the levels of ultrafine particles reached concentrations 10 times as high as a normal office or lab.

The test setup was simplicity itself.  The researchers put the printer in a sealed enclosure and vented it into a precision instrument for measuring such things.  Each of the five printers tested (FlashForge Creator, Dremel 3D Idea Builder, XYZprinting da Vinci 1.0, MakerBot Replicator 2X, and LulzBot Mini) spent between two and four hours printing out the same sample object. A particle counter tallied the number of ultrafine particles each test was spewing into the airtight room, while also sampling air quality for VOCs following the EPA's standards. They also tested more than a dozen materials, ranging from ABS and PLA to wood and clear polycarbonate.

The important question, of course is if this is a serious threat and printers like this are dangerous to be around.  It turns out that the answers aren't extremely clear, and it requires some careful reading.  Some materials are better than others.  Clearly, they're not extremely toxic - no one drops dead after sitting near a printer - but they aren't so benign that you should disregard them.  You can bet that NIOSH and some other agencies are either reading this or preparing to replicate the results and propose regulations.  The conclusion section of the original ES&T journal article is several paragraphs long and so too long to excerpt here, but let me grab a few points that seem relevant.

Measurements of UFP and individual VOC emission rates presented here have important implications for human exposure and health effects. For example, styrene, which is classified as a possible human carcinogen by the International Agency for Research on Cancer (IARC classification group 2B),(23) was emitted in large amounts by all ABS filaments and the one HIPS filament. Caprolactam was also emitted in large amounts by four of the filaments: nylon, PCTPE, laybrick, and laywood.  Although caprolactam is classified as probably not carcinogenic to humans,(24) the California Office of Environmental Health Hazard Assessment (OEHHA) maintains acute, 8-h, and chronic reference exposure levels (RELs) of only 50, 7, and 2.2 μg/m3, respectively.(25) We are not aware of any relevant information regarding the inhalation toxicity of lactide, the primary individual VOC emitted from PLA filaments.
...
The predicted styrene concentration in this configuration (150 μg/m3) would be approximately 20 times higher than the highest styrene concentration measured in commercial buildings in the U.S. EPA BASE study(31) and more than 20 times higher than the average concentration in U.S. residences.(32) There are also reports that suggest exposure to styrene at these concentrations could be problematic for human health.
...
Although we are not aware of any regulatory limits for indoor UFP concentrations, an increase in UFP concentrations to ∼58 000 cm–3 would be approximately 10 times higher than what we typically observe in indoor air in our office and laboratory environments and what has been reported as a typical 8-h average indoor concentration in schools.(35) However, it would only be moderately higher than typical time-averaged concentrations in homes(36) but lower than what is often observed in other microenvironments.(37)

The paper's conclusion ends with a recommendation for printer makers to develop safer printing fibers, at a time when the emphasis appears to be on developing more useful fibers, and it seems to me that the Iron Law of the Perversity of Inanimate Objects dictates that those will be opposites.  They also recommend that printer makers endeavor to make safer products, stating, "manufacturers should work to evaluate the effectiveness of sealed enclosures on both UFP and VOC emissions or to introduce combined gas and particle filtration systems".  Until now, printer makers have been driving to cut costs and have put out many open frame printers, which have the more immediate hazard of burning oneself on the table.   Putting printers in a sealed enclosure that filters the air it exhausts will put 3D printing into the realm of industrial machines that don't really belong in a house.  That's a whole 'nother level of big, difficult to make, and expensive. 

Of course if you have a printer and are concerned about exposure, one obvious answer is to vent it to the outside.  Perhaps use the printer under a stove's exhaust hood, if it really exhausts to the outside.  If you have babies or young children, keep them out of a room where a printer is running ABS plastics, because styrene vapors in low concentrations have been associated with a higher risk of lung infections in infants.  The short version I see is to treat a 3D printer like spray painting.  A booth vented to the outside would be great to have.  It's not unreasonable to consider putting the printer outdoors, if conditions allow. 

Studica's DaVinci jr. printer.  Being enclosed is a good start, but it's not going to be air tight and won't be filtering the air. 

But Why Would You Want One?

If I ever mention to friends that I built a large CNC metal working machine, and that it's actually the third CNC piece I own, I inevitably get a question like that title.  What would you want one of those for?

While I'm not particularly interested in doing this, one guy from the Sherline CNC Yahoo Group posted a summary of a major project that's just a lot of fun to look at.  It's a model replica of a Terminator T800 arm and hand.

Lots of details the website, including more articles full of details on how he built it.

Not your cup of tea?  How about an Orrery?

As you can see, that's a screen capture from a 7-1/2 minute video by Ken Toons of his construction of an orrery of the planets known to the ancients - just out to Saturn.  Turn the handle and watch their relative motions. 

I've talked about using the machine to work on some 1911s or other guns, but it's not very financially smart to build a $2500 or $3000 machine to make one $1000 gun.  Perhaps more than that because parts seem to be expensive when bought this way.  But this is really more my speed.

Not sure where I got that.  It was just a picture on Pinterest.  Actually, I'd like to know where to get the fixture or plans to make one!

Of course, these things are pretty cool to me, too.  I posted this video back in 2015:


I call those "external combustion engines" because the flame is outside the cylinder and it just operates by inhaling hot air and letting it cool.   One of those might be happening.

The Deep State Hit Job On Lt. Gen. Michael Flynn

It has been interesting to watch the news unfolding today detailing what appears to be nothing short of a hit job, a political career assassination, against Lt. General Michael Flynn by members of the Deep State.

The story several people seem to be quoting is the Washington Free Beacon's Adam Credo's article, alleging that the classified information was leaked to the press by Obama appointees in the CIA determined to preserve the Iran nuclear giveaway program deal.

The abrupt resignation Monday evening of White House national security adviser Michael Flynn is the culmination of a secret, months-long campaign by former Obama administration confidantes to handicap President Donald Trump's national security apparatus and preserve the nuclear deal with Iran, according to multiple sources in and out of the White House who described to the Washington Free Beacon a behind-the-scenes effort by these officials to plant a series of damaging stories about Flynn in the national media.

The effort, said to include former Obama administration adviser Ben Rhodes—the architect of a separate White House effort to create what he described as a pro-Iran echo chamber—included a small task force of Obama loyalists who deluged media outlets with stories aimed at eroding Flynn's credibility, multiple sources revealed.

A "secret, months-long campaign" means these agencies have been plotting to take him down since well before the inauguration.  Gen. Flynn was known as a critic of the Iran deal, and of the CIA for so badly bungling the management of the Mideast in the wake of the wind down in Iraq.  The Blaze adds:

Flynn was one of the most vociferous critics of the Iran Deal and ridding him from Trump’s administration helps the cause to keep the agreement in place, despite repeated statements by Trump that he would dismantle what he called, “the worst deal ever negotiated.”

The whole thing seems to go back to secret aspects of the Iranian deal, and the Deep State's desire to keep them secret.  They were scared Flynn was going to somehow let those secrets out.

A third source who serves as a congressional adviser and was involved in the 2015 fight over the Iran deal told the Free Beacon that the Obama administration feared that Flynn would expose the secret agreements with Iran.

"The Obama administration knew that Flynn was going to release the secret documents around the Iran deal, which would blow up their myth that it was a good deal that rolled back Iran," the source said. "So in December the Obama NSC started going to work with their favorite reporters, selectively leaking damaging and incomplete information about Flynn."

The laughable New York Times, living up to my version of their motto; "all the news we feel fit to make up",  tried to imply that the leak of information was to let the media know that Trump was colluding with the Russians during the election (yawn) but even the intelligence report put down that lie. The Times left out this important sentence.

The officials interviewed in recent weeks said that, so far, they had seen no evidence of such cooperation.

The most in-depth coverage seems to be from Patrick Poole at PJ Media (whom I've already quoted), and specifically gets into the legalities of what these "intelligence community" people did.  

House Intel Committee Chairman Devin Nunes is demanding to know why Flynn's conversations were being wiretapped. As one of the congressional "Big 8," if there were a covert program targeting Flynn, he would be one of the few to know:

“Any intelligence agency cannot listen to Americans’ phone calls,” Nunes told reporters Tuesday night. “If there’s inadvertent collection that you know is overseas there’s a whole process in place for that.”
...
“So in this case it would be General Flynn and then how did that happen. Then if they did that, then how does all that get out to the public which is another leak of classified information,” Nunes added. “I’m pretty sure the FBI didn’t have a warrant on Michael Flynn.” [bold in the original - SiG]

and

Here's Eli Lake at Bloomberg:

There is another component to this story as well -- as Trump himself just tweeted. It's very rare that reporters are ever told about government-monitored communications of U.S. citizens, let alone senior U.S. officials. The last story like this to hit Washington was in 2009 when Jeff Stein, then of CQ, reported on intercepted phone calls between a senior Aipac lobbyist and Jane Harman, who at the time was a Democratic member of Congress.

Normally intercepts of U.S. officials and citizens are some of the most tightly held government secrets. This is for good reason. Selectively disclosing details of private conversations monitored by the FBI or NSA gives the permanent state the power to destroy reputations from the cloak of anonymity. This is what police states do.

Trump famously said he intended to drain the swamp.  This swamp is filled with 12' long gators and they're fighting back.  The intelligence agencies and other political hacks are putting on a shameful display of insider politics at its worst.  While most commentators have talked about this for what it is, I heard Jason Buttrill on the Blaze, a former member of the intelligence community, talking like they just did the country a tremendous favor, but it sure doesn't sound that way to me.  It sounds like the intelligence community is trying to destroy the administration as John Robb talked about two months ago.  Apparently, it all centers on Obama appointees to the agencies trying to maintain what they view as their legacy.  Ben Rhodes, Deputy National Security Adviser for the Obama administration at the time, said that they viewed the Iran Deal as the Obamacare of his second term, meaning it was just as important to his presidential legacy.

Lt. Gen. Michael Flynn testifies during a hearing before the House Intelligence Committee. (Alex Wong/Getty Images)

Interesting DARPA VLF Program

DARPA, as you probably know, is the Defense Advanced Research Projects Agency and they have a respectable record of success in programs that are high risk but high payoff.

So it's with some interest that I hear they're working on a program to miniaturize Very Low Frequency antennas.  Actually, miniaturize is too weak a word.  See, antennas work best when they're a significant portion of a wavelength long (the wavelength times the frequency is always the speed of light: c = f*l).  As a rule of thumb, most amateur antennas are longer than 1/8 wavelength, and some are several or many wavelengths long.

For example, a relationship lots of hams know is that the length (in feet) to start working on a 1/4 wavelength antenna is 234/f where f is in MHz.  That says an AM radio antenna 1/4 wavelength long at 1.000 MHz (near the middle of the AM broadcast band) is 234 ft long.  DARPA wants to miniaturize that antenna to fit in a teacup, with room to spare.  They want antennas 1/10,000 of a wave long.  That turns the 234 foot tall antenna into 1.12 inches tall.

“At these frequencies, free‐space electromagnetic (EM) field wavelengths are measured in tens of kilometers, resulting in very large transmitter structures when employing conventional antenna approaches. Electrically‐small antennas are defined as having dimensions much smaller than the EM wavelength, with examples in the literature of antenna‐sizes as small as 1/10th of the EM wavelength. DARPA is seeking innovation to bring that size below 1/10,000 of the EM wavelength or by at least a factor of 10³ smaller than the current state of the art (SOA).”

Such a tremendous reduction in size is impossible to achieve through traditional antenna design so DARPA said it is looking to gather information “in the areas of materials, mechanical actuation, and overall transmitter architectures to address impedance matching, power handling, signal modulation, scalability, and other system level considerations.”

Unlike the world that car commercial writers live in, nobody can “break the laws of physics”, so nobody is going to come up with a way to treat those antennas to make them behave just like a full-sized antenna.  The laws of physics not can't be broken, nor are they up for negotiation.  On the other hand. they can be dealt with.  There may ..may ... be tricks that can be done to make a system work effectively with antennas that small.

The main problem is going to be the impedances required.  An electrically tiny antenna is barely distinguishable from an open circuit; they're a very, very high impedance.  Full sized antennas have much lower impedances, and most transmitter and receiver systems are designed around a 50 ohm standard impedance.  If you go buy virtually any amateur HF base station radio made in the last 50 years, that's what they'll be designed for.  Your cheap, Chinese VHF/UHF radio will be designed around a similar value.  (Cable TV systems, which don't transmit, are designed around 75 ohms for their cable ports rather than 50 ohms; car radio antennas are electrically quite small for AM radio, but not DARPA 1/10,000 wave "quite small", and they're high impedance). 

Half and quarter wave antennas are the impedance they are because of the physics.  They can be thought of as matching the impedance of the transmitter to the impedance of free space which is just under 377 ohms and any antenna has to match its impedance to 377 ohms.   The output impedance of the power device in the transmitter isn't 50 ohms just because the antenna is 50 ohms, and impedance matching is one of the very basic skills of an RF designer (impedance matching been berry berry good to me!).  The impedance of the output stage depends on the circuit configuration and device.  A convenient way to approximate the output impedance is the voltage squared over 2 times the power output ((Vcc^2)/(2*Po))  That means the higher the voltage and the lower the output power, the higher the output impedance. 

In a transmitter, low output power is rarely something desirable (I never, ever, had anyone ask me or anyone else I was ever around for less transmitter power).  Modern power transistors can run at hundreds of volts, but it seems to me that we'd be looking at even higher voltages to get the impedances they're looking for.  High voltage brings its own problems: notably arcing and corona, but high voltage is handled in the business. 

The biggest problems here are the antenna efficiencies.  An open circuit can only be tuned so far to look like an antenna.  It may require so many parts or be so narrowband that it becomes a useless antenna.  Component quality is going to be a big concern; it will likely require huge, heavily silver-plated coils and capacitors with vacuum dielectrics.  I don't know that the antenna can work.  It may turn out that the combination of extremely inefficient antennas, forcing higher powers to be used, forcing ever higher voltages into the circuits is simply insurmountable. 

I always used to say that the company that can turn the land requirements for an AM broadcaster from "many acres" down to "a store in a strip mall" will never run out of money.  The typical AM broadcaster uses three quarter wave tall monopoles (verticals), spaced around a quarter wave from each other, because they need to carefully recreate an antenna pattern they're authorized to use, so they'd need three of these magic antennas.  Once the radio waves leave that antenna, it's still a full-sized EM wave.  I just don't see how they can do it, but that's what DARPA is for.

The "Trideco" antenna tower array at the US Navy's Naval Radio Station Cutler in Cutler, Maine, USA. The central mast is the radiating element, while the star-shaped horizontal wire array is the capacitive top load. About 1.2 miles in diameter, it communicates with submerged submarines at 24 kHz at a power of 1.8 megawatts, the most powerful radio station in the world.  If scaled the way DARPA is targeting, that 979.5 foot tall tower becomes 11.75 inches.  It's currently 1/10 wave long; 11.75 inches reflects shrinking it by 1/1000.

Tweaking And Verifying the Mill - Part 2

It has been an interesting few days of continuing to try to improve my G0704.  The biggest improvement is that I reduced the Y-axis backlash to .001", which is better by far than anything else I have. 

In that process, I first put a handwheel on the Y-axis stepper motor, with the power off, of course, and found I could count the clicks of the stepper until motion started.  It started moving at six, which corresponds very closely to the .006" backlash I had.  (If my clicks are exactly 1/200 of revolution of the ballscrew, that's 5.91 thousandths).  I took apart the Y-axis drive chain and got into the familiar position of not being able to check the backlash because of the way the bearings work.  If I rotate the screw in one direction, I drive the table; if I unscrew it the other direction, the screw and all its bearings start coming out of the block they're sitting in.  I can push the parts back into place, but I need something like the motor mount to hold the bearings fixed in place.  So I made a tool.

This is just a piece of 1/8" scrap aluminum I had lying around after making the fret rocker.  It resembles the actual piece that goes there, except for being 1/8 instead of 3/8" thick, and other than the hole pattern being random size and shape.  Of course, I only put the holes in it that were needed.  Once I did this, I couldn't feel any backlash at all with a handwheel on the Y ballscrew.  Once I rebuilt the drive parts, I could measure the backlash at .001". 

Today, I tried to duplicate that fix on the X-axis but it flopped.  No improvement, so the backlash is still .006".  I need to think about this some more, and maybe try it again, but my gut feel is that it has to do with the order in which I did things on Y vs. the X, and pushing the ballscrew and bearings hard into their position and taking out all the slack there.  I might try that again.

The other issue I mentioned last week has also been resolved.  The issue was that I was getting 1/4 of the scale to movements I thought I should be getting.  One of the things that seemed to be coming from was the motor's microstep setting.  It can step in either 1/2 or 1/8 microsteps.  (Microstepping gives users the impression that they turn their 200 step motors into 400 or 1600 step motors.  It sort of does, but nobody guarantees the position accuracy of a microstepping controller.  It's done to smooth out the motion.)  There's a DIP switch along the top of the motor driver that allows setting some driver parameters, and the manual makes it seem like all we need to do is flip SW4 to change that from 1/2 to 1/8 and back.  Actually doing that made no difference. I have four motor drivers and not one of them changed when the switch was flipped. 

In the end, I sent the vendor, Automation Technology, Inc., a support email.  It apparently got lost because I had to resend it after last night's posting. They actually answered me by 11PM Sunday night (!!) and after swapping a couple of emails, they told me the correct way to configure the motor.  The most important part: there's a switch (SW6) that must be changed that isn't mentioned in the data sheet at all.  My system is now stepping in 1/8 steps, 1600 steps per rotation of the ballscrew, or 8128 steps to the inch.  That number is tweaked a bit for each axis in the last digit until the command to go 1.000" truly goes 1.000".  It's affected by just how accurately the 5mm pitch of the ballscrew is made to 5mm. 

Finally, I decided that my control box was just looking too darned plain, and needed something on the front panel.  By now, many if not most of you have seen my AR-15 from an 80% lower with the goofy cat on it; the goofy cat was chosen for a specific reason: the original version of this AR had mostly DPMS parts and it was sort of a nod to them.  DPMS has the fearsome looking panther as their logo, so I figured I'd use a goofy looking cat instead.  Between Mrs. Graybeard and I, the goofy cat has become somewhat of an emblem or logo. 

Add a bit of techno-magic and you get this:

I'd like to claim it's my work, but in reality it was reader John who has become a friend.  The work was done on a vinyl cutter, and it's the kind of vinyl decal that can be bought in many places. 

QoTD - An Excerpt From Come and Take It by Cody Wilson

Way back in October, I'd mentioned that I had gotten Cody Wilson's book, "Come and Take It".  I didn't find it terribly interesting or a particularly compelling read, but let me skip the book review and get right to the quote in question.  Of the roughly 300 pages, this exchange is the one that sticks with me.  It's about how the people who survived communism had something important destroyed in their souls. 

As setup, Cody is in various places in Europe working on raising funds to get Defense Distributed enough funding to complete the liberator pistol.  Shortly before leaving he has a late night talk with a former American, Mike, who has renounced his citizenship and left the States.

"These Slovaks," I said.  "I mean, it's a hideous race, isn't it?  You see it in how they walk,how they carry themselves.  Defeat is just bred into them."

"I think it's fair to say the legacy of State communism here today is with the people who are past middle age, generally fifty plus, if they're not part of the ruling elite.  They've learned a mentality that's beaten down, subservient.  No initiative, " Mike said.

His eyes searched around while he dragged on the cigarette he'd just lit with the butt of the first.  "But they've taught this to their children". 

Frankly, I find that heartbreaking.  More so than the other trials and problems Wilson went through in the book.  Millions of people, and millions yet to come have had something vital, something central to being human, sucked out of their souls by communism.