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Q4: Ernst Sachs made a big contribution to soldering in the 1920s. What was it?

Answer: Patented the first mass-produced electrical soldering iron

In 1921, Ersa founder Ernst Sachs patented what many consider to be the first mass-produced electrical soldering iron for industry. Of course, this was not the “first” electrical soldering iron. The American Electrical Heater Company was granted a patent for an “electric heating apparatus” in 1896 which might also be considered the first electrical soldering iron.

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Q5: What should be heated with a soldering iron?

Answer: The pad and component

A common beginners’ misconception is that only the solder itself needs to be melted. Unfortunately, adding hot solder to a room-temperature surface only peppers it with shiny metal globs. You might as well use glitter.

Solder goes where the heat is—especially if there’s a freshly-fluxed surface to flow onto. Warm up the pad, warm up the component, and the molten solder will go exactly where you want it.

Whether you’re splicing wires on a desk lamp or replacing surface mounted components on a circuit board, you need to heat up the workpiece.

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Q6: When should a soldering tip be discarded?

Answers: When the iron shows visible signs of corrosion and pitting

When the thermally-conductive copper center is exposed

Solder hates corrosion and pitting. It has no place on your iron. If the sensitive copper beneath the iron plating is exposed, it’s time to replace the tip.

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Q7: Which manufacturer developed an instant heat soldering iron?

Answer: Weller Tool company, in the 1940s

In 1946, Carl Weller was granted a patent for a soldering gun warmed up to operating temperature almost instantly. Thanks to his impatience, soldering pros have cumulatively saved centuries of waiting—five minutes at a time.

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Q8: What causes soldering iron tips to wear out?

Answers: Heating and cooling under normal use

Adding flux to the tip before storage

Exposing the copper center beneath the iron plating

Your soldering tips will wear out. The same flux that helps solder flow will slowly but surely wear away the iron plating of your soldering tips—each time you strip away a film of oxidation, the fresh metal beneath starts oxidizing. If that wasn’t enough, the normal heating and cooling of a soldering iron invites oxidation and pitting.

To get the most life out of your tips, clean them frequently. Applying fresh solder to a clean tip before putting it away can also help extend its life.

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Q9: Iver Anderson made an important contribution to soldering. What was it?

Answer: Developing lead-free solder at Ames Laboratory in 1996

The toxic nature of lead-tin solder has always been a health concern. By the 1990s, the relatively low melting points of lead and tin were becoming a performance concern. The Information Age demanded electronics that worked reliably in more extreme temperatures.

Anderson’s work addressed both problems. Today, lead-free solder is the norm.

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Q10: In the late 1950s, a new technology optimized soldering in electronics production. What was it?

Answer: Integrated circuits for electronic devices

Computers were once enormous. And slow. Improvement meant soldering more circuits—with each human-soldered circuit adding an extra potential for failure.

In 1958, Jack Kilby of Texas Instruments came up with modular blocks with built-in wiring—the first integrated circuits—which substantially reduced the amount of soldering required.

Now computers are tiny. And fast.