Author: Dave Farquhar

What solder mask is

Dave Farquhar Hardware
What solder mask is

Solder mask is a protective polymer coating applied to printed circuit boards that serves multiple purposes. Besides being an aid in the PCB manufacturing process, it also serves a reliability purpose.

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Why S traps are illegal in drains

Dave Farquhar DIY
Why S traps are illegal in drains

Are s traps illegal? Why? You may have heard S traps are illegal, without explanation. Or maybe you’ve wondered why you have to make a P trap under your drain when an S trap would be easier. Here’s why S traps are illegal in drains.

S traps are illegal because they cause a health and a safety hazard. But the conditions under whether you have to replace them do vary.
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What is Delrin?

Dave Farquhar Toy trains
What is Delrin?

Perhaps the most lasting legacy of Model Products Corporation on the history of Lionel trains was its use of a material called Delrin. And their competitors, including Marx and K-Line, quickly started using it too. But what is Delrin, and why was it better than the tried and true stuff Lionel Corporation used?

Delrin is a trademark of DuPont, a type of plastic called Polyoxymethylene POM. You can injection mold parts with it like other plastics such as styrene or ABS, but it is slippery and self-lubricating.

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Are electric lawn mowers quiet?

Dave Farquhar DIY
Are electric lawn mowers quiet?

Proponents of electric lawn mowers talk about the sound they make as an advantage. But are electric lawn mowers quiet for real, or is it just marketing talk?

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Can dogs spell?

Dave Farquhar Dogs
Can dogs spell?

Dogs can learn somewhere between 50 and 250 words or phrases. So that means humans will sometimes speak in code to avoid getting a dog excited. One of the most common forms of code is spelling the words. That works until dogs learn the spelling of those words. Wait. Dogs can spell?

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Is Windows XP obsolete or is it retro?

Dave Farquhar Retro Computing
Is Windows XP obsolete or is it retro?

Windows XP is hard to classify. I still remember when it was brand new, and technologically it’s closer to today’s versions of Windows than it is to Windows 98. To my kids, it’s ancient history. But what should we call it? Is Windows XP obsolete? Or is it retrro?

Whatever you call it, it shouldn’t be your everyday operating system anymore. I’ve talked before about what to do if you are still running XP and need something else to migrate to.

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How soon is too soon to get another dog? It depends

Dave Farquhar Dogs
How soon is too soon to get another dog? It depends

How soon is too soon to get another dog? Unfortunately I have experience in this area. But most dog owners do. And the amount of time I’ve waited varied. Here’s why.

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Qualys duplicate assets

Dave Farquhar security
Qualys duplicate assets

One of the most frequent problems people ask me about when doing a health check on their vulnerability management program is duplicate assets in Qualys. If you simply run the tool with the defaults, it is definitely possible to end up with duplicate assets. But with a few configuration changes, you can mostly eliminate this problem.

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Why electric lawn mowers are better than gas

Dave Farquhar DIY
Why electric lawn mowers are better than gas

Over the course of two decades of home ownership, I’ve gone through several gas mowers. In 2021, after my friends bought electric mowers and raved about them, I decided to buy one myself. So are electric lawn mowers better than gas? Let’s look at the pros and cons.

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Marx Oak Park station

Dave Farquhar Toy trains
Marx Oak Park station

The Marx Oak Park station is one of three tinplate train stations Marx produced during the post-war era. They replaced an earlier, smaller, and less ambitious station from the pre-war era, and solved more than one problem for Marx.

The Marx Oak Park station had a long production run, from around 1950 to 1973. Marx named the station after the home of a Sears executive they were negotiating with.

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