Thursday, April 30, 2020

3D PRINTERING: WILL A RESIN PRINTER RETIRE YOUR FILAMENT-BASED ONE? by Donald Papp

Adding a resin printer to one’s workbench has never looked so attractive, nor been so affordable. Complex shapes with effortlessly great detail and surface finish? Yes, please! Well, photos make the results look effortless, anyway. Since filament-based printers using fused deposition modeling (FDM) get solid “could be better” ratings when it comes to surface finish and small detail resolution, will a trusty FDM printer end up retired if one buys a resin printer?
The short answer is this: for users who already use FDM, a resin-based stereolithography (SLA) printer is not likely to take over. What is more likely to happen is that the filament printer continues to do the same jobs it is good at, while the resin printer opens some wonderful new doors. This is partly because those great SLA prints will come at a cost that may not always justify the extra work.
Let’s go through what makes SLA good, what it needs in return, and how it does and doesn’t fit in with FDM.

WHEN SLA IS GOOD, IT’S REALLY GOOD

Objects with organic curves and no real “up” or “down” are much better suited to SLA than FDM.
The sweet spot for resin printing is this: small objects with smooth finishes, organic curves, and surface details. With SLA, these objects print more reliably and at a consistently higher quality than with FDM — as long as the operator does a good job with layout and support placement, anyway.
A big reason for this is that SLA does not produce layer lines the way FDM does. FDM prints are notorious for visible layer lines, and those lines are at their worst when spread across curved surfaces. SLA still creates objects one layer at a time, but the process doesn’t leave obvious lines.
There is also more freedom in part orientation when printing in resin. Unlike FDM, resin prints are isotropic. In the context of 3D printing, this means that the printed object’s physical properties do not change with respect to physical orientation. As long as a part is supported enough to print properly, a resin printer doesn’t much care in which orientation or at what angle it builds an object; the result will come out the same. This gives SLA printers more flexibility when it comes to part orientation, which helps when trying to keep presentation surfaces and details free from supports.

NICHE APPLICATIONS FOR SLA’S STRENGTHS

One example of a niche for what resin printing is good at is gaming miniatures and figures. Tabletop enthusiasts are buying printers and resin, and designers of gaming-related models are finding success as well. The more successful ones thrive on sites like Patreon, with thousands of monthly supporters.
Engineering applications can have a place with SLA, so long as the objects are small enough. The build volume of most SLA printers is revoltingly tiny compared to FDM, but they make up for it with the ability to handle shapes and details that FDM would have problems with.

BEWARE SLA’S ADDED COSTS

SLA printing brings some annoying buddies everywhere it goes in the form of added costs. These aren’t costs for the machines themselves; hobbyist SLA printers are very affordable. These ongoing costs are for consumables, increased time for upkeep and part processing, and storage space.
SLA requires more setup and cleanup than FDM. Printed parts need to be washed (usually in an alcohol bath) after printing, and possibly post-cured with additional UV exposure. Since resin is messy, disposable gloves and a spill-resistant work area are required. Another thing to consider is that resin isn’t meant to be left sitting in a printer for long periods, so when printing is done for the forseeable future, it’s time to empty the printer and clean the parts.
All of this takes time, but it also takes up valuable space in a work area. Bottles of resin, containers of alcohol, wash bins, gloves, a drip-proof work space, all of it takes up storage and table space. SLA printing as a whole will take up far more room than just the printer itself.
The other thing to consider is the need for manual post-processing. Resin prints tend to require a lot of supports, and those supports need to be removed by hand. These leave behind small marks that may need to be sanded away. With FDM, supports are a last resort that are used only if needed, but with SLA they are the rule rather than the exception.

THINGS FDM IS STILL GOOD AT

A well-maintained FDM printer is a fantastic tool for prototyping, iterating on designs, and creating functional parts. FDM also has other advantages that really stand out when contrasted with resin printing.
FDM is perfectly happy to wait patiently until needed, at which point a print can be started with a minimum of fuss. The consumables are few and reasonably priced. Filament is best stored in a dry environment, but besides that, it doesn’t ask for much. Swapping filament types or colors is simple, clean, and easy. Even a failed print doesn’t usually involve much more than sweeping away a mess of plastic and trying again.
The biggest disadvantages are related to layer line visibility, the resolution of surface detail, and working with curved organic shapes. None of these can be waved away, but they can be mitigated to some extent. Variable Layer Height tries to address layer line visibility, and it is a feature that has worked its way into most slicer software. The ability to render very small details and features can be improved, to some extent, by swapping a printer’s standard 0.4 mm nozzle for a smaller one.
FDM printers are most challenged by being asked to print curved objects that have no flat areas and no real “up” or “down”. One option is splitting these objects into smaller and more easily-printed ones, but that’s not always practical. Printing a tricky model will require supports, and supports with FDM always result in degraded surface quality. Water-soluble support structures can help mitigate this, but doing so requires multi-material printing. SLA, on the other hand, is far more suited to such objects.

IS THERE ROOM FOR BOTH?

Resin prints look fantastic and it may be tempting to think of SLA as superior to FDM, but that is not the whole story. They are different tools, and good at different things. Unless your needs are very specific, you’ll probably benefit from access to both.
If you need to print small objects with good surface finish and detail resolution, and you can deal with the added hassles of working with resin, then SLA is definitely for you. But even if you only print small objects, a working FDM printer can easily earn its place on your workbench with the ability to create functional parts without any significant setup and cleanup. If you’re considering an SLA printer, don’t plan to ditch FDM just yet.
I regularly use both but personally, I always choose a filament-based printer if possible; even if a final model will eventually be printed in resin, it’s simply cheaper and faster and easier to prototype and iterate with FDM.
If you have access to both, has this also been your experience? Do you know of a niche for resin printing that hits the spot in a way nothing else does, the way SLA has done with tabletop enthusiasts? We want to hear all about it, so let us know in the comments.

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Coronavirus and the Risky Mix of Bailouts, Big Business, and Big Government April 29, 2020 by Dan Mitchell

Since government officials have imposed severe restrictions on economic activity, I’m sympathetic to the notion that businesses should be compensated.
But, as I warn in this CNBC interview, I have major concerns about big government and big business getting in bed together.
As is so often the case with interviews on live TV, there are many issues that didn’t get appropriate attention (either because there was too little time or because I failed to address a key point).
  • major risk of bailouts is that politicians will insist on having a say in how companies operate. Indeed, that’s what Christian Weller was calling for in the final part of the interview. I should have pointed out the huge economic downside of having government in the boardroom.
  • There’s a rationale for short-run emergency legislation, but we should be very concerned that self-interested politicians and power-hungry bureaucracies will use the coronavirus crisis as an excuse to permanently expand their power and control over the economy’s productive sector.
P.S. I usually try to avoid making predictions (economists are lousy forecasters), but I feel confident in asserting that my friends on the left – once the coronavirus crisis has ended – will be complaining about big businesses having too much power.
I’m not against large companies, per se. But I don’t want bigger firms to gain an advantage over small companies by getting in bed with government.
If we want fair and honest competition, we need separation of business and state. No bailouts, no cronyism, no subsidies, and no favoritism.
That’s the part folks on the left don’t understand.
P.S. If you want more information on the economic damage caused by bailouts, watch this video and this video.
P.P.S. Speaking of videos, here’s some satire about the toys that politicians get for their children.
P.P.P.S. I wish this was satire, but American taxpayers are helping to underwrite cronyism in other countries.

The COVID-19 and Spanish Flu Pandemics, A Century Apart By Donald W. Miller, Jr., MD

My wife and I began the new year completing a two-week holiday cruise to Hawaii on the Star Princess, sister ship to the Diamond Princess, returning to Los Angeles on January 3. Our flight home was uneventful. All seemed well. In February, the Dow Jones Industrial Average hit an all-time high (29,551 on Feb 12). Nothing to worry about.
Then came a virus virologists name “SARS-CoV-2” (Severe Acute Respiratory Syndrome-CoronaVirus-2) which causes “Covid-19” (Coronavirus disease, beginning in [November?] 2019). On January 20, a man in the Seattle area who had recently returned from visiting family in Wuhan, China had a fever and dry cough and was found to be infected with Covid-19.
Mortality
As of April 28, 2020, in the U.S., 1,011,6000 people have tested positive for Covid-19 (Covid) with 58,343 deaths.Pale Rider: The Spanis...Spinney, LauraBest Price: $24.05Buy New $15.49(as of 04:12 EDT - Details)
The 1918-1920 influenza pandemic (Spanish flu) killed 675,000 Americans. One of them was my grandmother Mary Ashby Warden Williams. Several weeks before she fell ill and suddenly died, her stepmother, Mary Lyde Hicks Williams (my great grandmother), a professional portrait painter, painted this portrait of Mary Ashby with her 18-month old daughter Charlotte (my mother) standing next to her. Mary Ashby died in January 1920 at the tail end of the pandemic, age 23. Her daughter endures and will be 102 in July.
My wife’s grandmother Agnes Posten, an Irish immigrant, also died in that pandemic, age 26.
More than 30 million Americans had the Spanish Flu in a  population of 105 million and with 675,000 deaths, a 2.3% fatality rate. “Fast forward” to today. The Director-General of the UN’s World Health Organization (WHO), Tedros Ghebreyesus, an Ethiopian politician (and former leader of a terrorist group)—the first non-physician to head this body—declared that Covid-19 has a 3.4% mortality rate. With a rate this high Covid could kill many millions of people worldwide. This spawned a global panic. The Director-General, however, left out people who become infected with this virus, did not get tested and didn’t get sick. Up to 80% of people who test positive for Covid either have no symptoms or only mild ones imitating  a cold. Counting them in the equation, the mortality rate for Covid in Wuhan, China would be closer to 1.4% than 3.4%.
The 1918-20 influenza pandemic killed between 15 and 100 million people worldwide, 0.8% to 5.6% in a population of 1.8 billion (see here). Now, with the population 7.8 billion, one of comparable lethality could kill between 60 to 430 million people.
The “Spanish” flu started in Kansas. It spread in 3 main waves. The first one, from March to June 1918, was relatively mild. Soldiers called it “the 3-day flu.” It was seldom fatal, with a mortality rate near 0.5% (5 deaths in a thousand cases), close to seasonal flu of 0.1%.
The second wave, from August to December, was more lethal. One observer noted, “While the first wave of flu in 1918 was relatively nonlethal, the second made up for it in spades.” Two million American soldiers were shipped to Europe to fight with the Allies (France, Britain, and Russia) in World War I against the Central Powers (Germany and its allies). More soldiers died from the flu than in battle. Laura Spinney, in Pale Rider: The Spanish Flu of 1918 and How It Changed the World writes:The Great Influenza: T...Barry, John M.Buy New $13.99(as of 02:52 EDT - Details)
“[Flu] Patients would soon be having trouble breathing. Two mahogany spots appeared over their cheekbones, and within a few hours that color had flushed their faces from ear to ear… [If it turned blue] the outlook was bleak indeed. Blue darkened to black. The black first appeared at the extremities—the hands and feet, including the nails—stole up the limbs, and eventually infused the abdomen and torso. As long as you were conscious, therefore, you watched death enter at your fingertips and fill you up.”
The Spanish flu targeted healthy young adults. People between age 20 and 40 were the high-risk group. Their robust immune systems would launch a “cytokine storm”—a cellular (macrophage)-induced severe inflammatory reaction, both against the virus and oneself. Flooding one’s lungs, this “storm” could kill a person within 24 hours after the onset of symptoms.
(The nations fighting in World War I censored any mention of this pandemic, which laid waste to both sides. Spain remained neutral and did not censor its newspapers, thus the name “Spanish flu.”)
Debate continues over Covid’s case mortality rate. The number of Covid deaths is falsely high in jurisdictions where people who die with the virus (test positive for Covid) in actuality die from a pre-existing condition (heart disease, cancer) and get included with people who die from the virus. And there are Covid-positive people who remain asymptomatic that are not counted, which also makes the case mortality rate falsely high. To remedy that everyone in a given population must be tested.
After testing positive for Covid one develops antibodies—immune markers in serum indicating prior exposure to a specific pathogen. Antibody tests will capture all previously infected cases, including the asymptomatic ones, thus supplying the correct fraction for calculating the case mortality rate. Controversy currently exists, however, over the sensitivity and specificity of the new antibody tests for SARS-CoV-2. A low specificity yields false positives of supposedly asymptomatic cases, a larger denominator and thus a falsely low case mortality rate.
Elderly people with pre-existing conditions are the high-risk group with Covid; but a growing number of studies show that its overall lethality is lower than initially thought, somewhere between 0.1% and 0.4%, in the seasonal flu range. Most healthy older adults without pre-existing conditions do well and have immune systems strong enough to handle the virus.The Vitamin D Revoluti...Soram KhalsaBest Price: $1.25Buy New $10.69(as of 08:00 EST - Details)
The Diamond Princess finished a roundtrip 15-day tour of Southeast Asia from Japan on February 2, 2020. It had 3,711 passengers and crew—2,666 passengers (median age 69) and 1,045 crew (median age 36). Some passengers tested positive for Covid on the cruise, and Japanese authorities quarantined the ship when it docked back at Yokohama—its passengers for up to three weeks and crew, four weeks. Health workers tested almost everyone on board for Covid and found that 712 (19.2%) were infected—567 passengers (21.2%) and 145 crew members (13.8%). There were 14 deaths (0.4%), only in elderly passengers. Analyzing the data from this “ship laboratory,” researchers estimate that the mortality rate from Covid in China is around 0.5%, like in the first wave of the Spanish flu.
SARS-CoV-2 is one of seven coronaviruses. Several of them cause the common cold. Two other dangerous coronaviruses, SARS-CoV and MERS-CoV (“Middle East Respiratory Syndrome”) kill people. The 2002 SARS epidemic caused 770 deaths and the 2015 MERS epidemic, 850 deaths. But they did not come in several waves. The current coronavirus may not come back in a second wave either.
Evidence shows SARS-CoV-2 is bioengineered. A Biosafety Level 4 laboratory in Wuhan, China released this new coronavirus, presumably by accident. Migrating water birds spread the Spanish flu virus to humans.
Lockdown
During the Spanish flu, until the Armistice of November 11, 1918 ended World War I, President Wilson kept the nation fixed on fighting and winning the war. He did not let a worsening influenza pandemic interfere. John Barry, in his The Great Influenza: The Epic Story of the Deadliest Plague in History, writes this about the state of American society in 1918:
“Wilson’s hard line threatened dissenters [against the war] with imprisonment. The federal government also took control over much of national life. The War Industries Board allocated raw materials to factories, guaranteed profits, and controlled production and prices of war material, and, with the National War Labor Board, it set wages as well. The Railroad Administration virtually nationalized the American railroad industry. The Fuel Administration controlled fuel distribution (and to save fuel it also instituted daylight savings time). The Food Administration—under Herbert Hoover—oversaw agricultural production, pricing, and distribution.”
Responding to the Covid pandemic, the nation has simply shut down, economically and personally. Computer models greatly overpredicted the deaths it would cause. They predicted that more than two million Americans would die from this infection (even factoring in mitigation), as compared with 30,000 seasonal flu deaths. This prompted government officials to shut down the economy and order people to stay home. Along with its predictions, however, Imperial College modelers did acknowledge this: “We do not consider the ethical or economic implications of either strategy [suppression or mitigation]” (emphasis added).
Adverse consequences from the lockdown on human health and behavior include domestic violence, child abuse, and the risk of suicide, followed by civil unrest and crime waves. These consequences are yet to fully appear and be measured but they will be substantial and likely overshadow Covid deaths. Hospitals have halted “elective” surgeries for people who suffer other diseases. Delaying them also carries risk.
A more unrestricted approach is better. While shielding vulnerable senior citizens, younger people who have a negligible Covid mortality risk should be able to go to work, to restaurants and bars (and church), like in Sweden. People there do go to work, cafes and restaurants are open, and its parks full. The country remains open for business.
Covid-infected people who have mild illness help establish widespread immunity against subsequent and possibly more virulent waves of the infection.
Treatment
There were no vaccines for the Spanish flu. But vaccine companies a century later are working nonstop to develop one for Covid. But human trials to confidently establish a vaccine’s efficacy and safety take time, 18 months or more. Of note, 93% of vaccine trials fail.
Vaccines for flu viruses have a checkered history. Public health officials had to recall the one made for the 1976 Swine flu when it was found to cause Guillain-Barré Syndrome—immune system damage with slowly progressive paralysis ending in death. Vaccine officials promoted the vaccine Pandemix for the 2009 Swine flu and fast-tracked it without the requisite clinical trials. This vaccine caused narcolepsy—difficulty sleeping at night associated with night terrors, hallucination, and mental health problems.Vitamin D3, Zinc and M...Jeffers, NancyBest Price: nullBuy New $6.98(as of 03:40 EST - Details)
Lacking a vaccine or an effective antiviral drug against Covid, physicians search for any pharmaceutical agents that might be effective in treating it. The Trump-hating media, notably the New York Times, Washington Post, CNN, and MSNBC chastised President Trump for promoting the antimalarial drug chloroquine (hydroxychloroquine) for Covid-19. Long used for treating malaria, hydroxychloroquine prevents single cell malarial parasites from invading red blood cells and eating their hemoglobin. Research shows that SARS-CoV-2 also attacks red blood cells, rendering its hemoglobin incapable of transporting oxygen to the body. An intensive-care physician describes how patients who become seriously ill from Covid suffer more from hypoxia—a lack of oxygen—than from viral/bacterial pneumonia. Covid is more like high altitude sickness (here). The way hydroxychloroquine shields red blood cells from malarial parasites can explain how this drug could also do the same thing against this coronavirus. (See Dr. Dave Janda’s interview with Karen Whitsett, Democratic member of the Michigan House of Representatives on her experience with hydroxychloroquine.) As one blogger sees it, “Covid-19 had us all fooled, but now we might have finally found its secret” (here).
Thirteen years ago I researched and wrote, “Avoid Flu Shots, Take Vitamin D Instead.” It remains relevant, as this March 2020 review of the subject confirms. In one study, 86% of all Covid patients with normal vitamin D levels (30 ng/ml or above) had a mild illness, while 73% of cases that became severe or critical had a vitamin D deficiency (less than 20 ng/ml). Vitamin D switches on genes in immune-system macrophages that make antimicrobial peptides, antibiotics the body produces to attack and destroy invading bacteria and viruses.
Vitamin C given intravenously in high doses is proving to be an effective way to salvage critically ill Covid patients. Zinc, which suppresses virus activity, also helps; but one has to be careful with zinc.
For the Spanish flu some physicians advised patients to take Aspirin, up to 30 grams a day. A dose that high is toxic and can cause a buildup of fluid in the lungs—pulmonary edema. Aspirin was a relatively new drug in 1918. (Physicians today consider 60 to 300 milligrams, 0.06 to 0.3 grams, to be the best dose for aspirin.)
Depression
Miller’s Review ...Miller, Neil Z.Best Price: $8.32Buy New $14.48(as of 04:45 EST - Details)The Covid pandemic has pricked the debt-fueled Everything Bubble and precipitated a Greater Depression. Maintained with multi-trillion-dollar bailouts, it could persist for years, like the Great Depression did. Michael Pento sees it this way: “This [Greater Depression] is a global depression just like we had in the 1930s combined with a 2008 style credit crisis.” Doug Casey: “We’ve entered a downturn that is going to be longer, deeper, and different than the unpleasantness of 1929-1946.” And Jim Quinn: “When ATM machines stop spitting out twenties, food shelves are bare and gas stations are shuttered, social chaos will ensue.”
Zerohedge.com reports that for every Covid death 565 Americans have lost their jobs. And “Nearly one in three Americans have experienced a temporary layoff, permanent job loss, reduction in hours, or reduction of income as a result of the coronavirus situation. Eighteen percent have experienced more than one of these disruptions.” The Federal Reserve Bank of St. Louis estimates that the unemployment rate in the U.S. could reach 32.1% in the second quarter as 47 million workers are laid off, easily eclipsing the 25% rate during the Great Depression.
In 1918 Americans used gold and silver coins to buy things and pay debts. Paper dollars (Federal Reserve Notes) were redeemable in gold. Federal Reserve Notes today have become a fiat currency and have lost 98% of their original value. Since 1971 the dollar has also fallen 98% in real terms measured in gold. Government’s unlimited printing of dollars will accelerate as more companies and financial institutions default, courting hyperinflation.
The 1920-21 Depression followed the Spanish flu. The Dow Jones Industrial Average dropped 47%, industrial production fell 32%, and corporate profits, 92%. The government did not provide any “fiscal stimulus” to cure this Depression. Tax rates were lowered, the national debt reduced by one-third, and the economy recovered quickly on its own. (See The Forgotten Depression, 1921: The Crash that Cured Itself by James Grant.)
(On April 6, 1919, President Woodrow Wilson caught the Spanish flu in Paris during peace negotiations. He became quite ill, returned home, and four months later had a severe stroke. Without his tempering input, the punitive Treaty of Versailles set the stage for World War II.)
Brave New World
Curing the Incurable: ...Best Price: $12.95Buy New $44.02(as of 03:06 EDT - Details)Narrative managers would have Americans live obediently observing Covid shutdown orders. They do not want to see doctors present arguments for lifting the lockdown. After going viral with 5 million views, YouTube deleted the video of two California doctors who support the case that states should begin reopening their economies.
Today Americans are becoming increasingly compelled to live under an authoritarian technocracy, as Whitney Webb describes in “Techno-Tyranny: How the US National Security State is Using Coronavirus to Fulfill an Orwellian Vision.” In order to keep up with China in artificial intelligence, the Covid pandemic is enabling the Pentagon, intelligence community, and Silicon Valley to implement AI mass surveillance systems. They are removing obstacles that have prevented their implementation “under the guise of combating the coronavirus crisis.”
The U.S. National Security Commission on Artificial Intelligence, created by the 2018 National Defense Authorization Act, cites three “legacy systems” holding back adoption of AI-driven technologies: cash and credit/debit card payments, individual car ownership, and receiving medical attention from a human doctor. In their place would come financial transactions done only with smart phones (and computers), ride-sharing driverless cars, and AI robotic medical care. Plus, authoritarian technocrats would have us stop shopping in stores (many of which are going bankrupt in the lockdown) and buy everything online, enabling them to more easily track our purchases.
The “Spanish” flu occurred in the spring of American imperialism, which started in 1898 with the Spanish-American War and Spain ceding its ownership and control of the Philippines and Guam to U.S. forces. World War I turned the United States into a full-fledged imperial power. Now, sparking the Greater Depression the Covid pandemic arrives in what is becoming winter of American imperialism.
For more on where the country is heading over the next six years, I recommend reading (or rereading) “World War Redux: The Fourth Turning Fourth Time Around.”