2020-06-08

Notes, 2020-06-08.

On an average week this newsletter is opened by between three and five thousand people. A well-performing link will be clicked by between ten and twenty-five percent of the people who open the email - conservatively 500 clicks.

This week I want to direct you all here, as The Prepared is matching up to $10,000 in donations you make to organizations fighting for civil rights and against inequality and police brutality. Your donation doesn't need to be large, and you can direct it to the organization of your choice; also if you’re not able to make one yourself then just send a note and we’ll make one in your name. If you're unsure where to give, we recommend the NAACP Legal Defense Fund, Campaign Zero, and The National Bail Fund Network.

This won't, of course, solve anything. The big, broken systems our society suffers from are not exactly hot-swappable, and it'll take continuous and concerted effort from all of us to make a meaningful change. As always, please reach out if you know of something else that The Prepared should be doing to help. I'm here; I see you; I'm trying to do better.

The link to click, again, is here. And thanks.

The most clicked link from last week's issue (~13% of opens) was @likebuttermelbourne's clever wire clip corner connector.

Planning & Strategy.

• I am one year older than China’s patent law system. I’m also reading Henry Kissinger’s On China, and recommend John Pomfret’s The Beautiful Country and the Middle Kingdom.

Making & Manufacturing.

• NYC CNC cuts a Higbee thread. Higbees (aka blunt start threads) prevent cross threading and are prominently used in fire hose connections, of which there are apparently *many* standards.
• A fun, silly, and rather successful effort to build a billows system that’s quieter and as effective as conventional computer fans.
• Building a robotic golf club that adjusts its angle of attack based on user-input range and IMU swing data.
• In nature oysters grow to be all sorts of shapes, but restaurants prefer them uniformly sized with a deep cup on one side. Oyster farms grade & cull oysters accordingly, sending “selects” to restaurants and “standards” to shucking houses to be processed in bulk. To increase yield of “selects,” some oyster farms use a tumbling system that literally bangs the oysters around a little, breaking off new growth. This encourages the oysters to focus on growing thick shells with deep cups. See also this good explainer on the many different oyster “grow-out” methods.

Maintenance, Repair & Operations.

• Wastewater treatment plants often use CO2 to control acidity. About a third of the US supply chain for CO2 comes as a byproduct of ethanol production, an industry that has been hit by a) the dozens of exemptions that Trump has awarded to oil refineries, allowing them to discontinue using ethanol in gasoline, and b) OPEC’s breakdown earlier in March, which resulted in a lot of cheap oil entering the market. The net effect is a shortage in industrial & food grade CO2, which both Washington State’s Office of Drinking Water and FEMA seem to agree could be an issue for local water treatment facilities.
• “I shipped a word processor that formatted the hard drive every 1024 saves.”

Distribution & Logistics.

• Matthew Hockenberry’s delightfully complete syllabus of reading material on logistics and its contexts. This is quite the list, with links that span mining & extraction, production, operations, containerization, and countless other fields. A really fantastic resource, which any reader of this newsletter should enjoy.
• “A wax motor is a linear actuator device that converts thermal energy into mechanical energy by exploiting the phase-change behaviour of waxes.” Wax expands by up to 20% when it melts, and when heated a small volume of wax can be used to push a piston with force on the order of 4000N.
• Iowa-class battleships had top speeds of around 33 knots, and by reversing their screws and turning both of their rudders inboard (a “barn door stop”) they could come to a halt in about 600 ft.

Inspection, Testing & Analysis.

• Christopher wrote in about the battery study we linked to last week, noting that AmazonBasics’ pricing scales nicely (down to $0.27/ea at 100) while Energizer Ultimate Lithium pricing is basically flat at $1.25/ea in wholesale quantities. This undermines the conclusion that the Ultimate Lithium gives the best value per kWh. Related: Battery University is a really remarkable collection of both basic (How to prolong lithium-based batteries) and niche (Why does Pokémon Go rob so much battery power?) battery-related knowledge.
• Wind tunnel testing a scale model of the Golden Gate Bridge, whose new bike lane guards hum pretty loudly in a stiff breeze.
• Atmospheric CO2 is at its highest level ever recorded, “a reminder that climate change is not on pause in any way, shape or form.”
• An interactive map of the marine regions (economic zones, territorial seas, etc) of the world.

Tangents.

• An old humor piece from The New Yorker, which I linked to in 2014-08-01 and which serves as a good reminder of the kind of radical change people are capable of when they truly try: The Day Coffee Stopped Working.

Maps of police & military helicopters' flight paths in the past week.