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What is solder made of?

Dave Farquhar DIY April 12, 2022April 3, 2022

Solder is a mixture of relatively low melting point metals, designed to melt at a lower temperature than metals like copper. This allows you to join components, providing a strong chemical bond that is electrically conductive. So what is solder made of? It’s made of a special mixture of metal. Frequently it also contains a core with chemical additives to make it easier to work with.

The precise formulation of both the solder alloy and the core varies depending on the application. But, generally speaking, solder is made of an alloy of low melting point metals.

f strings in Python

Dave Farquhar Software April 11, 2022March 15, 2023

When you first encounter f strings in Python, they can seem like a dark art. And you can use them without understanding them. I’ve used f strings to get myself out of a bind, based on a code snippet I found on Stack Overflow or some other discussion board, with a comment saying not to ask me why it works. But here’s what they do and how they can help your code.

In memoriam: Angel, 2005-2022, best dog ever

Dave Farquhar Personal April 8, 2022April 27, 2024

It was the summer of 2006. We had been married a little over a year, and we decided together it was time to get a dog. We started looking, and buying the stuff we needed. Then one fateful Saturday, we took a trip to the Humane Society on Macklind Avenue.

We had a good idea what we were looking for. We had no idea we were going to find all that and more.

No Ox ID for model railroading

Dave Farquhar model railroading April 7, 2022April 14, 2022

In 1965, Linn Westcott, the longtime editor of Model Railroader magazine, wrote an article about how he never cleaned the track on his layout. His secret was a product called No Ox ID A Special. Let’s talk about No Ox ID for model railroading.

What flux is made of

Dave Farquhar DIY April 6, 2022April 12, 2022

Flux is a chemical compound that makes soldering much easier. Flux serves two purposes, cleaning oxides and other impurities from metal surfaces and helping the solder to flow. What flux is made of varies depending on the purpose.

Frequently you can tell what flux is made of from the color. If it’s white, it’s probably acidic and meant for plumbing, and if it’s a weird shade of amber, it’s made of rosin and suitable for electronics.

What is a DOS game?

Dave Farquhar DOS, Retro Computing April 5, 2022February 28, 2025

It seemed like an innocent enough question to me. Two game developers were talking, one older than the other, and the older said something about developing a DOS game, and then the younger asked, what’s a DOS game?

A DOS game is a game that runs on PC hardware but under MS-DOS or PC DOS rather than Microsoft Windows.

Why circuit boards are green

Dave Farquhar Hardware April 4, 2022May 17, 2022

Why are circuit boards green? It’s a matter of practicality. While circuit boards aren’t always green, green provides technical advantages. So that makes green the most common color for printed circuit boards, or PCBs.

Unique Art Manufacturing Co of New Jersey

Dave Farquhar Toy trains March 31, 2022April 1, 2022

Unique Art Manufacturing Co of New Jersey was a manufacturer of tin lithographed toys, based in New York City and Newark, New Jersey. It was founded in 1914 and faded away between 1951 and 1955. Its president, Samuel Berger (not Bergman), was an inventor with at least four patents to his name, and his company was one of the few U.S. makers of tin lithographed toys in the postwar era.

There is a great deal of incorrect information floating around about the little known company, including the name of its president and founder.

Tandy 1000 vs PCjr

Dave Farquhar Retro Computing March 30, 2022September 24, 2023

The Tandy 1000 vs PCjr is a natural comparison. The Tandy 1000 is exactly the computer the IBM PCjr should have been. That means there are similarities, but it also means significant differences. So here’s what they were. It goes a long way toward explaining why one was a notorious flop and the other was a raging success.

Where is Route 66 in St. Louis?

Dave Farquhar St. Louis March 29, 2022March 26, 2022

Where is Route 66 in St. Louis? Two Missouri highways, 366 and 100, claim to be the old Route 66. Why? Because it changed over the years. Both have legitimate claims to Route 66 heritage, so let’s talk about the history, how far apart the roads are, and what makes both of them interesting.

There were at multiple alignments of Route 66 through St. Louis from 1926 to 1975, so no wonder it’s complicated. The two major ones are the 1926-32 version, along the modern MO-100, and the post-1932 version, which is approximately MO-366. There was also a bypass route, which served approximately the same function as the modern I-270/I-255 outerbelt today, but it was closer to the city, and all on the Missouri side.