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mech987

102 karma · joined December 7, 2021

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mech987··on A Whale-Oiled Machine
You should watch videos on how hard head gaskets are to design if you want an idea of some of the engineering involved- I think "engineering explained" did one recently on youtube.
mech987··on Bank failures come in waves
That is a fair point- although when the increases are large enough in such a small time that the prior/posterior calculations are that different, I don't feel like it inspires confidence.
mech987··on Bank failures come in waves
Here's the data on M2 money supply in billions of dollars, for those curious, in billions of dollars:

Feb 2020: 15,457.9 Feb 2022: 21,699.2

This is a 40.3% increase.

To be charitable, this money isn't all on printed physical cash dollar bills, but nowadays there is no need for it to be. (I'm tempted not to be charitable though.)

https://fred.stlouisfed.org/series/M2SL

mech987··on The teen mental illness epidemic began around 2012
I don't think any of the people you are having a discussion with are making the claims you think they are making.
mech987··on EVs catch fire far less often than gas-powered cars, firefighters need to adapt
I've been keeping an eye on LiFePO4 batteries- they should be less likely to have a "thermal event" than lithium ion. Some manufacturers are putting them in cars now. Less energy dense but cheaper and better cycle life before wearing out. I want to see those in a 10 year old EV I can buy affordably!
mech987··on The Pretty Good House
I think if there is condensation between the panes then the sealed air cavity inside the window has been compromised- you might want to get a new window put in.

The large double glazed sliding glass door in one of my previous apartments had that issue, and it eventually became mold trapped inside the glass that was uncleanable.

mech987··on The Spaceballs Argument for Unconditional Basic Income
It is a comparison in the same spirit as the original article.
mech987··on We need a lot more electricians
insulation-displacement-crimps are not a good idea for the relatively high amounts of power coming through household wiring. Not much contact area, lots of potential for high resistance and heat and oxidation at the contact point. I wouldn't trust them.

Then again, wire nuts aren't that great either.

mech987··on We need a lot more electricians
UK homes run on 230 volts, so each amp is worth double what US amps are worth (running on 115 volts in the US) edit: 115 volts per leg, and US has 2 legs, so it comes out in the wash, surprisingly. UK homes have tiny little service amps!
mech987··on On Mr. Beast and being alone in a circle for 100 days
Seems to me that people are much more upset about this particular video (guy in circle for 100 days) because he's a husband and father. If it had been a young 20-something person, nobody would bat an eye.
mech987··on Gas Leak in the Baltic Sea
I've only thought about it for a minute- but I might speculate that it is a signal from Russia- "even if we decide we want to turn the gas back on, you might not be able to get it when you want it."
mech987··on 2000-Watt Society
You are confusing the watt and the watt-hour. Running a 2000 watt load for 24 hours will use 48,000 watt-hours (48 kilowatt-hours).
mech987··on Taxing Mechanical Engineers and Subsidizing Drama Majors
I'm not sure how things will look by the time my daughter might be ready to go to college in 18 years-

Would it be best for us to sock away money in a 529 plan, or to just let her take out loans to the greatest extent possible and pay them back after the fact?

mech987··on The anti-inflation pivot of 2022
>The risk is that it will be excessively contractionary and will trigger a worldwide recession

>Those who advocate a tightening of fiscal and monetary policy in the name of stopping inflation, do so because they fear a build up of inflationary momentum. That risk may be real. No less real, however, are the costs of the contractionary policy mix being applied now.

My intuition on the problem is that no matter where we fall along the spectrum once it lands, we will have both unacceptably high inflation (which we've already had) and an unacceptably large recession. Don't know which one will hurt more yet.

mech987··on My First BillG Review (2006)
You conflated some of my claims about the hypothetical company with claims about Microsoft in particular. I think that the root of it gets down to disagreement in values about how capitalism rewards innovators though, so it's unlikely we'll resolve any of that disagreement today. I might as well say my piece.

>However, consider how disconnected their actions are from their financial reward...

Operating at a high executive level in a corporation is necessarily abstract and disconnected. Bill Gates's most tangible actions were early on, starting the company and taking the risk and creating the first bits of the software. It's turned out that many software products have high margins once established, and high network effects as well. By the time somebody is focusing their attention on the biggest winners among the highest margin, most scalable industries, at the peak of their career success, they can forget the other less-successful founders whose products help people everyday and are awarded in more reasonable proportion. It's tough to know how many of these other founders would have even started a worthwhile business without the potential reward of wild amounts of wealth.

FWIW, I would appreciate it if co-ops were more common as a corporate structure. I've got no beef with that existing, and it is indeed possible for it to exist within the U.S. legal system. I figure that it all comes down to incentives. And as far as Bill's wealth goes he's doing a pretty good job of giving it to people in greater need of it than the average software developer.

mech987··on Mortgage Rates Jump Above 6%, Putting Pressure on Housing Market
I think we're seeing the culmination of a long-term trend of declining interest rates. Interest rates have been declining for 400 years, and have finally reached the point where they bottom out at 0. (or even negative interest rates, in European bank policy!).

The bad part of this I think, is that valuations of long-term cash flows start becoming more and more sensitive to rates. The difference between a 2.75% mortgage and a 3.75% mortgage is bigger, relatively, than the difference between a 3.75% mortgage and a 4.75% mortgage; because people buy the largest, longest mortgage they can afford, small changes in small interest rates result in large changes in the monthly payment. I feel like this ends up making the whole housing market more volatile.

mech987··on My First BillG Review (2006)
As a pure test case-

Let's say there was an individual who founded a company, owned 100% of the equity, and designed a brand new product. The product solved an unmet need for consumers, sold at high profit margins, and was massively successful. Our inventor was well ahead of his time, and the next-fastest similar invention would've been invented 30 years later, during which time $500 billion of consumer value had been created. Would you admit in this case that the founder earned a substantial fraction of the $500 billion?

To what degree is Bill Gates' wealth similar to this test case versus network-effect-capture, first-mover-advantage wealth? How do you quantify the value of Microsoft's software quality earning it's substantial market share, versus Microsoft getting there first and squatting on the network effect?

mech987··on The Grim Secret of Nordic Happiness: Reasonable Expectations
You're free to give as much extra taxes to the government as you want to help reduce the debt and get us closer to that sovereign wealth fund. I'd appreciate it.
mech987··on Sierra Club, environmental groups petition EPA to ban natural gas for heating
Isn't heating a really good way to use natural gas compared to other ways to use it? 90%+ efficiency ain't bad.
mech987··on How Bad Europe’s Energy Crisis Is
Because they have a vested interest in understanding the parts of the global economy that affect their competitors.
mech987··on Increased wind turbine rotor blade visibility to reduce avian fatalities
That 20,000 number is off by at least an order of magnitude just for US bird wind turbine deaths. Turbine construction has been accelerating, so the 2013 numbers cited below are low.

https://abcbirds.org/blog21/wind-turbine-mortality/

mech987··on Jackson, Mississippi, to go without reliable drinking water indefinitely
There should be no risk to using untreated water to flush the toilet.

Presumably they are shipping two types of water- potable and non-potable. The non-potable is less difficult to produce and ship.

You can flush a toilet by dumping a bucket of water into the bowl.

mech987··on More energy on less land: The drive to shrink solar’s footprint
Is PV at the same land use as coal currently on a per-watt basis or on a total land use basis?
mech987··on A group of activists got leaf blowers banned in the nation’s capital (2019)
Gasoline engines struggle to produce torque at very low RPM's, so once they begin choking on the fibers in the chaps, they lose momentum and stop.

Electric motors on the other hand produce peak torque at 0 RPM, so it's way harder to bring them to a standstill.

Many of these electric chainsaws are premium brands and still have this problem- to my knowledge there are no electric chainsaws that have a safety feature designed to make sure chaps work.

The clever safety feature that could be engineered to help make these safer is to add a torque sensor to the motor that cuts off power if excessive torque is sensed. This excessive torque condition would hopefully be calibrated to not have any nuisance shutoffs, but can still stop the saw when needed for safety.

mech987··on What Happens When Texans Protest Their “Mind-Boggling” Property Taxes?
If the city can buy property at 90% of appraised value, they can sell to the market at true market value. As long as their appraised value is accurate, they profit from this arrangement.

It provides the proper incentive to align appraisals with market value and prevents the city from exploiting its citizens.

mech987··on High property taxes are good
Weird to see Chicago used as an example of good governance.
mech987··on Corn Cobs: Fuel of Nightmares
"Shigley's Mechanical Engineering Design" is a great textbook if you want to learn the most you can with the fewest books about designing mechanical structures and moving parts from a strength perspective.

Fluid flow/ thermo would be the other main academic area that this book wouldn't cover.

There's a bunch more topics though that you build over years of intuition- manufacturability, design tradeoffs, etc.

mech987··on Us crosses the electric-car tipping point for mass adoption
I kinda feel like cars are a pretty good transportation solution to poor land use planning.
mech987··on Us crosses the electric-car tipping point for mass adoption
The amount of solar power hitting the surface of a car is much, much smaller than the power driving the wheels.
mech987··on The euro and the dollar are a penny away from parity for first time in 20 years
I've been expecting Germany will turn their nuclear plants back on soon, given the Ukraine situation. Haven't seen it happen yet though.
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