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Deadly screw sizes, avoid odd numbers and UNF.

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The glory of American screws and bolts is their low cost ubiquity, especially in our coarse thread (UNC = United National Coarse) sizes. Between 1/4 inch and 5/8″, they are sized in 1/16″ steps, and after that in 1/8″ steps. Below 3/16″, they are sized by wire gauges, and generally they have unique pitch sizes. All US screws and bolts are measured by their diameter and threads per inch. Thus, the 3/8-16 (UNC) has an outer diameter (major diameter) of 3/8″ with 16 threads per inch (tpi). 16 tpi is an ideal thread number for overall hold strength. No other bolt has 16 threads per inch so it is impossible to use the wrong bolt in a hole tapped for 3/8-16. The same is true for basically every course thread with a very few exceptions, mainly found between 3/16″ and 1/4″ where the wire gauges transition to fractional sizes. Because of this, if you stick to UTC you are unlikely to screw up, as it were. You are also less-likely to cross-thread.

I own one of these. It’s a tread pitch gauge.

US fine threads come in a variety of standards, most notably UNF = United National Fine. No version of fine thread is as strong as coarse because while there are more threads per inch, each root is considerably weaker. The advantage of fine treads is for use with very thin material, or where vibration is a serious concern. The problem is that screwups are far more likely and this diminishes the strength even further. Consider the 7/16″ – 24 (UNF). This bolt will fit into a nut or flange tapped for 1/2″- 24. The fit will be a little loose, but you might not notice. You will be able to wrench it down so everything looks solid, but only the ends of the threads are holding. This is a accident waiting to happen. To prevent such mistakes you can try to never allow a 7/6″-24 bolt into your shop, but this is uncomfortably difficult. If you ever let a 7/6″-24 bolt in, some day someone will grab it and use it, in all likelihood with a 1/2″ -24 nut or flange, since these are super-common. Under stress, the connection will fail in the worst possible moment.

Other UNF bolts and nuts present the same screwup risk. For example, between the 3/8″-24 and 5/16″-24 (UNF), or the #10-32 (UNF) and also with the 3/16″- 32, and the latter with the #8-32 (UNC). There is also a French metric with 0.9mm — this turns out to be identical to -32 pitch. The problem appears with any bolt pair where with identical pitch and the major diameter of the smaller bolt has a larger outer diameter (major diameter) than the inner diameter (minor diameter) of the larger bolt. If these are matched, the bolts will seem to hold when tightened, but they will fail in use. You well sometimes have to use these sizes because they match with some purchased flange. If you have to use them, be careful to use the largest bolt diameter that will fit into the threaded hole.

Where I have the option, my preference is to stick to UNC as much as possible, even where vibration is an issue. In vibration situations, I prefer to add a lock nut or sometimes, an anti-vibration glue, locktite, available in different release temperatures. Locktite is also helpful to prevent gas leaks. In our hydrogen purifiers, I use lock washers on the ground connection from the power cord, for example.

I try to avoid metric, by the way. They less readily available in the US, and more expensive. The other problem with metric is that there are two varieties (Standard and French — God love the French engineering) and there are so many sizes and pitches that screwups are common. Metric bolts come in every mm diameter, and often fractional mm too. There is a 2mm, a 2.3mm, a 2.5mm, and a 2.6mm, often with overlapping pitches. The pitch of metric screws and bolts is measured by their spacing, by the way, so a 1mm metric pitch means there is 1mm between threads, the the equivalent of a 24.5 pitch in the US, and a 0.9mm pitch = US-32. Thread confusion possibilities are endless. A M6x1 (6mm OD x 1mm pitch) is easily confused with a M5x1 or a M7x1, and the latter with the M7.5×1. A M8x1.25 is easily confused with a M9x1.25, and a M14x2 with an M16x2. And then there is confusion with US bolts: a 2.5mm metric pitch is nearly identical to a US 10tpi pitch. I can not rid myself of US threads, so I avoid metric where I can. As above, problems arise if you use a smaller diameter bolt in a larger diameter nut.

For those who have to use metric, I suggest you always use the largest bolt that will fit (assuming you can find it). I try to avoid bringing odd-size bolts into their shop, that is, stick to M6, M8, M10. It’s not always possible, but it’s a suggestion. I get equipment with odd-size metric bolts too. My preference is to stick to UNC and to avoid odd numbers.

Robert Buxbaum, January 23, 2024. Note: I’ve only really discussed bolt sizes between about #4 and 1″, and I didn’t consider UNRC or UNJF or other, odd options. You can figure these issues out yourself from the above, I think.

Germany is the biggest loser in a long Ukraine war

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Early in the Ukraine War with Russia, Poland sent 200 T-72 battle tanks to Ukraine. Most other NATO members joined in, sending tanks, missiles, guns, supplies and technology. Germany sent nothing and have continued to avoid helping Ukraine as much as possible while the war dragged on for a year. Germany seems to have hoped for a quick Russian victory leading to a quick return to the pre-war, state of affairs. That’s not likely. Even early on, the war looked like a slow, long slog. Reluctantly, this month, Germany promised to send 18 Leopard tanks to Ukraine, requesting as replacements, mothballed tanks from Switzerland.

Germany is currently the 4th largest economy in the world, just behind Japan, and ahead of India (for now). They also have the 3rd oldest population. Their place as the leading economic and political power in Europe rests on a close relationship with Russia that is fading, bringing Russian goods west and manufacturing with them. Before the war, Germany imported most of its oil and 65% of its natural gas from Russia. Much of the gas came via two direct pipelines, Nord Stream, that bypassed the rest of Europe. Well into the war, while the rest of Europe disengaged, Germany is still buying from Russia and funneling it west: steel, aluminum, titanium, ammonia and platinum. Germany is still buying some Russian natural gas by way of Poland. The German economy is based on turning these materials into cars, high tech machines, and chemicals for export to the US, the EU, and China. Despite the very old population, Germany counts on cheap labor from low wage EU nations. These transient, long term. workers do not get citizenship or retirement benefits. The current war has presented Germany with more potential workers, Ukrainian refugees, but far fewer Russian supplies. The German economy is shrinking, and so far, the Ukrainian refugees have been mostly left unemployed.

Ex German Chancellor, Gerhard Schroeder, with Putin. He’s now head of Nordstream and Rosneft.

German industrial production is down by about 4% this year leaving its GPD at about $4T/year, about where it was in 2018. The US economy and the rest of Europe has grown. For an explanation, consider Germany’s ex-chancellor, Gerhard Schroeder, shown at left with Putin. Schroder remains a leader in the ruling SDP party, the party of Ms Merkel and of the current chancellor. He is also the chairman of the board for Nord Stream AG and of Rosneft, (Russian aerospace). He also sits on the board for Gasprom (Russia’s energy conglomerate), Rothschild, a prominent International bank, and is chairman of the board of the Hannover 96 football club. He is symbolic of Germany’s attachment to Putin and Russia. But the rest of the EU, along with the rest of the developed world, has come to hate Putin and Russia (they’re not too fond of Rothchild either). Europe is unlikely to tolerate Germany’s Russian imports, including titanium (65% of Airbus titanium comes from Russia) or natural gas. Germany has asked for a titanium exception (and been denied). What’s more, three of the four Nord Stream pipelines have been blown up (by whom?) leaving Germany to buy natural gas from its NATO allies: Norway, Britain, France Holland, and the US. Gas purchases are expensive for Germany while helping its NATO neighbors — Germany has asked to be subsidized for energy too (unlikely, imho). It has also restarted old coal-burning power plants, an insult to the EU given how hard Germany pushed them on climate change.

Germany is now near recession. Much of Europe is close, but Germany is worse-off since they are buying from the rest.

Percent of population over 65, CIA Factbook.

Much of the EU can sell gas and food to Germany, and Russia can export to China, India, and Iran. German inflation averaged 8.5% last year (9.2% in January). That is not hyperinflation, but a shock for a country that’s averaged 1% inflation over the last 25 years. US inflation, by comparison was 7.5% last year — due to excess spending by the Democrats (imho), the so- called “inflation reduction act,” but at least the US economy grew, along with the US population. It seems to me that, without Russian supplies, Germany will continue to slip versus the world and versus the EU.

Excess mortality for European countries has been very high for the last 6 months, especially in Germany. Death rates are up by 25% or so. Much of it is heart-related. Perhaps it’s COVID, or long COVID, or air pollution, or vaccines, or depression.

The German population is dying too. They too among the highest percent population over 65, see map. The death rate has spiked 25% over the last 6 months, too. Europe and much of the EU saw similar spikes earlier in the pandemic, partially from COVID, the rest is alcoholism, drugs, the vaccine, pollution, or a psycho-somatic response to isolation and the war. Sweden has largely avoided these problems so far.

Germany has been propping up its inefficient industries with low cost loans. The idea, presumably, is that things will go back to normal soon, and the companies will make good. So far, the war goes on, and the loans discourage competition and modernization. It becomes ever more likely that these inefficient German companies will default. If so, they could take down their lenders as happened in Japan in the 90s, and as happened to Lehman Bros. in the US. The same seems likely for China.

It becomes ever more likely that these inefficient German companies will default.

Even if the war ended tomorrow, it’s not clear that Germany could go back to its pre-war status. The blown Nord Stream pipelines will need a year or more to repair. And may never restart, as sanctions might remain long after the fighting ends, as with Cuba or North Korea. Russia seems to have recognized this possibility, and has begun sending titanium, gas, and oil elsewhere, mostly to Iran, India, and China. Iran has become a major customer of Russian aluminum, and food, and is a major supplier of drones and consumer goods to Russia. In the last two years, the Iranian GDP has doubled to about $2T/year. It is now nearly half the size of Germany’s GDP and growing while Germany shrinks.

Russia’s trade with India and China has grown too. They are working to improve the Trans-Iranian railroad that would allow easy shipments from Russia to India and China via the port of Tehran. The first direct shipment of this sort was completed in July 2022– Caspian Sea containers to an Iranian train to ship to India and China. If the war goes on, Iran, India, and China will benefit at the expense of Germany, it seems. India, in particular. India’s economy is already approaching the size of Germany’s, and will probably pass it with the help of Russia’s energy and raw materials. Meanwhile, Germany is left with an aging population and aging industries; with few suppliers, and no obvious competitive advantages. Europe is almost as badly positioned, but they can still sell to Germany. As for Ukraine, it seems to be doing well, despite the war — or because of it. They still grow and export food and energy, and they are holding their own in the war, for now. There is destruction in the east, but Ukraine might come out stronger, as happened with South Korea and Vietnam. Russia too seems to have found new customers and might come out OK. It is hard to see how Germany comes out well. This, at least, is how I see things today.

Robert Buxbaum, March 8, 2023.

The argument for free trade is half sound

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In 1900, the average tariff on imported goods was 27.4% and there was no income tax. Import tariffs provided all the money to run the US government and there was no minimum wage law. The high tariffs kept wage rates from falling to match those in the 3rd world. Currently, the average tariff is near-zero: 1.3%. There is a sizable income tax and a government income deficit; minimum wage laws are used to prop up salaries. Most economists claim we are doing things right now, and that the protective tariffs of the past were a mistake. Donald Trump claimed otherwise in his 2016 campaign. Academic economists are appalled, and generally claim he’s a fool, or worse. The argument they use to support low tariffs was made originally by Adam Smith (1776): “It is the maxim of every prudent master of a family, never to attempt to make at home what it will cost him more to make than to buy…. If a foreign country can supply us with a commodity cheaper than we ourselves can make it, better buy it of them with some part of the produce of our own industry.” As a family benefits from low cost products, a country must too. Why pay more?  How stupid would you have to be to think otherwise?

A cartoon from Puck 1911. Do you cut tariffs, and if so how much. High tariffs provide high wages and expensive prices for the consumer. Low tariffs lead to cheap products and low wages. Uncle Sam is confused.

A cartoon from Puck, 1911. Should tariffs be cut, and if so, how much. High tariffs provide high prices and high wages. Low tariffs lead to low prices for the consumer, but low wages. Uncle Sam is confused.

Of course, a country is not a family, and it is clear that some people will benefit more from cheap products, others less, and some folks will even suffer. Consumers and importers benefit, while employees generally do not. They are displaced from work, or find they must compete with employees in very low wage countries, and often with child labor or slave labor. The cartoon at right shows the conundrum. Uncle Sam holds a knife labeled “Tariff Revision” trying to decide where to cut. Any cut that helps consumers hurts producers just as much. Despite the cartoon, it seems to me there is likely a non-zero tariff rate that does not slow trade too much, but still provides revenue and protects American jobs.

A job-protecting tariff was part of the Republican platform from Lincoln’s time, well into the 20th century, and part of the Whig platform before that. Democrats, especially in the south, preferred low tariffs, certainly no more than needed to provide money for government operation. That led to a diminution of US tariffs, beginning in the mid- 1800s, first for US trade with developed countries, and eventually with third world as well. By the 1930s, we got almost no government income from tariffs, and almost all from an ever-larger income tax. After WWII low tariff reductions became a way to promote world stability too: our way of helping the poor abroad get on their feet again. In the 2016 campaign, candidate Donald Trump challenged this motivation and the whole low-tariff approach as anti- American (amor anti America-first). He threatened to put a 35% tariff on cars imported from Mexico as a way to keep jobs here, and likely to pay for the wall he claimed he would build as president. Blue-collar workers loved this threat, whether they believed it or not, and they voted Republican to an extent not seen in decades. Educated, white collar folks were uniformly appalled at Trump’s America-first insensitivity, and perhaps (likely) by the thought that they might have to pay more for imported goods. As president, Trump re-adjusted his threat to 20%, an interesting choice, and (I suspect) a good one.

The effect of a 20% tariff can be seen better, I think, by considering a barter-economy between two countries, one developed, one not: Mexico and the US, say with an without a 20% tax. Assume these two countries trade only in suits and food. In the poor country, the average worker can make either 4 suits per month or 200 lbs of food. In the developed country, workers produce either 10 suits or 1000 lbs of food. Because it’s a barter economy with a difference in production, we expect that, in the poor country, a suit costs 50 lbs of food; in the rich country, 100 lbs of food. There is room here to profit by trade.

The current state of tariffs world-wide. Quite a few countries have tariffs much higher than ours. Among those, Mexico.

Tariffs world-wide. While we put no tax on most imported products, while much of the world taxes our products rather heavily.

With no tariff, totally free trade, an importer will find he can make a profit bringing 100 lbs of US food to Mexico to trade for 2 suits. He can return two suits to the US having gotten his two suits at the price of one, less the cost of transport, lawyers, and middlemen (relatively low). Some US suit-makers will suffer, but the importer benefits immediately, and eventually US consumers and Mexican suit workers will benefit too. Eventually, US suit prices will go down, and Mexican wages up, We will have cheaper suits and will shift production to produce what we make best —  food.

In time, we can expect that an American suit maker will move his entire production to Mexico bringing better equipment and better management. Under his hand, lets assume his Mexican workers make 6 suits per month. The boss can now pay them better, perhaps 100 lbs of food and two suits per month. He still makes a nice profit, more than before: he ships two suits to the US to buy the 200 lbs of food, and retains now two suits as profit. Hillary Clinton believed this process was irreversible. “Those jobs are gone and they’re not coming back,” her campaign told CNN. She claimed she’d retrain the jobless “for the jobs of the future” and redistribute the wealth of the rich, a standard plank of the democratic platform since 1896. But for several reasons industrial voters didn’t trust her. Redistribution of wealth rarely works because, for example, the manufacturer can keep his profits off-shore, as many do.

While a very high tariff would stop all trade, but lets see what would happen with Trump’s 20% tariff. With a 20% tariff, when the first two suits come to the US, we extract 0.4 suits in tax revenue, but nothing on export. The importer still makes a profit, but it’s now 0.6 suits, the equivalent of 60 lbs of food. He can sell his suits for less than the American, but not quite as much less. If the manufacturer moves to Mexico he makes more money than by trade alone, but not quite as much. Tax is still collected on every suit brought to America — now 20% of the 3 suits per Mexican worker that the Boss must export. The American worker’s wages are depressed but he/she isn’t forced to compete with the Mexican dollar-for-dollar (suit for suit). In barter terms, he isn’t required to make 6 suits for every 100 lbs of food.lincoln-national-bank-internal-improvements-tariffs

Repeating the above for different tax rates, we find that, in the above fictional economy a 50% tariff in the maximum to allow any trade (or the minimum rate to stop trade completely): the first two suits might enter; but they’d be taxed at one suit, just enough to pay for the 100 lbs of food. There would be no profit for the importer, and he/she would stop importing. At 50% tariff, we would get no new goods, and we’d collect no new revenue – a bad situation. Lincoln’s “protective tariffs” of 1861 may have contributed to Southern succession and the start of the civil war. While there is a benefit to trade, it seems to me that some modest tariff (10%, 20%) is better for us — a conclusion that Trump seems to have intuited, and that many other countries seem to have come to, too (see map-chart above). As for the academic economists, I note that they also predicted that stock market crash should Trump be elected; it’s gone nearly straight up since November 8, 2016. For experts on money, I find that most economists are not rich.

Robert E. Buxbaum, March 27, 2017. I learned such economics as I have from my one course in economics, plus comic books like the classic “Once upon a dime” produced by the New York Federal Reserve. Among the lessons learned: that money is a distraction, just a more convenient way to carry around a suit, 100 lbs of food, or a month of work. If you want to understand economics, I think it helps to work things out in terms of barter. As

In praise of tariffs

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In a previous post I noted that we could reduce global air pollution if we used import taxes (tariffs) to move manufacture to the US from China and other highly polluting countries. It strikes me that import tariffs can have other benefits too, they can keep US jobs in the US, provide needed taxes, and they’re a tool of foreign policy. We buy far more from China and Russia than they buy from us, and we get a fair amount of grief — especially from Russia. An appropriate-sized tariff should reduce US unemployment, help balance the US, and help clean the air while pushing Russia in an alternative to war-talk.

There is certainly such a thing as too high a tariff, but it seems to me we’re nowhere near that. Too high a tariff is only when it severely limits the value of our purchasing dollar. We can’t eat dollars, and want to be able to buy foreign products with them. Currently foreign stuff is so cheap thought, that what we import is most stuff we used to make at home — often stuff we still make to a small extent, like shoes, ties, and steel. An import tax can be bad when it causes other countries to stop buying from us, but that’s already happened. Except for a very few industries, Americans buy far more abroad than we sell. As a result, we have roughly 50% of Americans out of well-paying work, and on some form government assistance. Our government spends far more to care for us, and to police and feed the world than it could possibly take in, in taxes. It’s a financial imbalance that could be largely corrected if we bought more from US manufacturers who employ US workers who’d pay taxes and not draw unemployment. Work also benefits folks by developing, in them, skills and self-confidence.

Cartoon by Daryl Cagle. Now why is Russia a most favorable trade partner?

Cartoon by Daryl Cagle. Trade as foreign policy. Why is Russia a most favorable trade partner?

In a world without taxes or unemployment, and free of self-confidence issues, free trade might be ideal, but taxes and unemployment are a big part of US life. US taxes pay for US roads and provide for education and police. Taxes pay for the US army, and for the (free?) US healthcare. With all these tax burdens, it seems reasonable to me that foreign companies should pay at least 5-10% — the amount an American company would if the products were made here. Tariff rates could be adjusted for political reasons (cartoon), or environmental — to reduce air pollution. Regarding Russia, I find it bizarre that our president just repealed the Jackson Vanik tariff, thus giving Russia most favored trade status. We should (I’d think) reinstate the tax and ramp it up or down if Russia invades again or if they help us with Syria or Iran.

A history of US tariff rates. There is room to put higher tariffs on some products or some countries.

A history of US tariff rates. Higher rates on some products and some countries did not harm the US for most of our history.

For most of US history, the US had much higher tariffs than now, see chart. In 1900 it averaged 27.4% and rose to 50% on dutiable items. Our economy did OK in 1900. By 1960, tariffs had decreased to 7.3% on average (12% on duty-able) and the economy was still doing well. Now our average tariff is 1.3%, and essentially zero for most-favored nations, like Russia. Compare this to the 10% that New York applies to in-state sales, or the 6% Michigan applies, or the 5.5% that Russia applies to goods imported from the US. Why shouldn’t we collect at least as high a tax on products bought from the non-free, polluting world as we collect from US manufacturers.

Some say tariffs caused the Great Depression. Countries with lower tariffs saw the same depression. Besides the Smoot-Hawley was 60%, and I’s suggesting 5-10% like in 1960. Many countries today do fine today with higher tariffs than that.

Robert E. Buxbaum, March 25, 2014. Previous historical posts discussed the poor reviews of Lincoln’s Gettysburg address, and analyzed world war two in terms of mustaches. I’ve also compared military intervention to intervening in a divorce dispute. My previous economic post suggested that Detroit’s very high, living wage hurt the city by fostering unemployment.