Author: Dave Farquhar

What flux is made of

Dave Farquhar DIY
What flux is made of

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.

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What is a DOS game?

Dave Farquhar DOS, Retro Computing
What is a DOS game?

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.

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Why circuit boards are green

Dave Farquhar Hardware

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.

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Unique Art Manufacturing Co of New Jersey

Dave Farquhar Toy trains
Unique Art Manufacturing Co of New Jersey

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.

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Tandy 1000 vs PCjr

Dave Farquhar Retro Computing
Tandy 1000 vs PCjr

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.

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Where is Route 66 in St. Louis?

Dave Farquhar St. Louis
Where is Route 66 in St. Louis?

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.

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Cast iron vs ductile iron vs steel

Dave Farquhar DIY
Cast iron vs ductile iron vs steel

I heard a discussion at a hardware store about the types of metal that tools are made of, and the impact it has on cost and on flexibility. I thought it was worthwhile to share and elaborate on some of what I heard. What’s the difference between cast iron vs ductile iron vs steel? Generally, it’s strength, hardness, and flexibility. And those factors generally come down to the carbon mixture.

Ductile iron is a form of cast iron, but it has carbon mixed into the alloy to make it more flexible, less brittle, and give it a higher strength overall. Steel is also a mixture of carbon and iron, but it has less carbon than ductile iron, the precise mix depends on the properties you want. Read more

Lionel Scout motor repair

Dave Farquhar Toy trains
Lionel Scout motor repair

The plastic Lionel Scout motor is legendary. I don’t mean in a good way. It worked well enough when it was new, but it didn’t age as well as Lionel’s other motor designs. And Lionel Scout motor repair is notoriously difficult.

The usual advice on Scout motors goes something like this. If it works, enjoy it while it lasts, but once one of them stops working, having a professional fix it costs more than the whole locomotive is worth. It’s nothing like the Marx motor it competed with, which is legendary for its simplicity, reliability, and being easy to fix. But while it’s certainly a hassle, you can fix a Scout motor that runs poorly, and you can do it yourself with household tools.

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What was a Token Ring network?

Dave Farquhar Retro Computing
What was a Token Ring network?

What was a Token Ring network? Token Ring is an obsolete networking technology that competed with Ethernet in the 1980s and 1990s. It is more of a curiosity today, but sometimes Token Ring network cards turn up and they can be confusing.

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What is lithium grease used for

Dave Farquhar DIY
What is lithium grease used for

Lithium grease is a useful lubricant with a lot of applications around the home and shop. You may be familiar with it if you do your own mechanical work, but even if you’re like me and you don’t, it can make your life easier in a lot of ways.

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