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by BluePen7 1072 days ago
It's funny, in high school due to social perceptions I didn't align myself with the "shop kids", and took exclusively computer-based electives.

It's led me to a lucrative career in programming, but now all my hobbiest time is actually spent learning the same hands-on skills I would have gotten in shop class, I love doing automotive repairs, I even learned how to fix my own AC system, and want to learn to weld.

Electrical is the tricky one because it's the one with the most consequences for mistakes. I wish there was a "electrician lite" night school or something.

8 comments

Grab some Arduinos, LEDs and buttons/switches and you'll learn about electricity pretty quickly with no real risk. It'll get you to a point where you should be comfortable enough working on mains electricity because you'll understand what's dangerous and what isn't.

And if you're in the US and a healthy adult, you're probably not going to kill yourself if you take a zap at 120V/15A.

Everything after "Grab some Arduinos, LEDs and buttons/switches and you'll learn" is terrible advice.

Wiring mains circuits is about craftsmanship and the ability to repeatably follow technical rules for low probability events that were nevertheless "written in blood". Tinkering with electronic circuits is not going to get you the engineering rigor you need to come at mains circuits from first principles.

You certainly can learn DIY house wiring safely as its own thing! The point is that they are just completely different skillsets, and you shouldn't be extrapolating confidence from low voltage circuits into mains wiring.

Also no, while 170 volt mains voltage (US residential peak voltage) is not likely to "kill" you, the actual risks are things like house fires from short circuits and intermittent connections. If you're doing anything where you're worried about getting "zapped", you're doing things horribly wrong in the first place.

I disagree regarding how much overlap there is between low voltage skill sets and high voltage skill sets. Even though the consequences are different, understanding when the circuit is energized and not is important, understanding the path of current flow is important, and lots of other concepts intuitively overlap.

For most household wiring tasks, turning off the circuit at the breaker box is the main safety provision. Using a wire nut properly is a bit tricky but not the worst thing in the world, and I don't trust a rushed contractor to tighten a wire nut any better than myself.

There is overlap for design/analysis. The problem is that overlap is insufficient to do mains wiring safely. Engineers doing their own work is an inspector cliche for a reason.

> Using a wire nut properly is a bit tricky but not the worst thing in the world, and I don't trust a rushed contractor to tighten a wire nut any better than myself.

This ties right into my point though. Low power circuits generally don't use wire nuts, and even when they might, they don't use thicker solid wires generally used for mains wiring. So you most likely learned wire nuts as their own separate skill, rather than from low voltage circuit work. My point is you've got to learn all those mains details in their own right, rather than thinking it's just like low voltage/power wiring.

(I totally agree about trusting yourself versus a rushed contractor! Emphatically yes - please do learn to DIY! My point is about the learning path to get there)

Oh I'm comfortable with DC, and am unafraid of low voltage tinkering.

For mains it's not the 120V zap I'm particularly worried about, it's the possible fire that occurs months later while I'm asleep because of some rookie mistake I made (connection that gets loose and starts to spark or something), that endangers anyone in the structure.

If I could have all the danger upfront and while I'm actively working on it (like woodworking), and limited to just myself, I'd be much more comfortable.

> Electrical is the tricky one because it's the one with the most consequences for mistakes.

I disagree. Woodworking is WAY more dangerous.

I have had exactly one mishap working with eletricity over the years. Somebody wired a piece of industrial equipment backwards (neutral as hot) and I got the shit shocked out of me.

I have had quite a few near misses in woodworking even while being amazingly aware. I know of no old woodworker who has all of his fingertips.

This video is about woodworking injuries gotten by YouTube streamers (CAUTION: Graphic!):

https://www.youtube.com/watch?v=Xc-lIs8VNIc

The one I never thought about was the final one (the table saw accident). It was a dual combination failure. He took an injury on his right arm which drew all his attention which then caused an accident with his left hand.

Yeah, I'm a big believer in safety equipment, even when it's inconvenient, after thinking about that one.

I guess not necessarily the "most" consequences, but the best hidden (at least to me as a novice).

When woodworking, I'm aware of the spinny bit and can watch a quick video on how to use the tool safely. And it's only a danger to myself (or anyone in the very immediate vicinity), while in active use.

My fear about electricity is the hidden dangers, or how things can seem to work fine up for hours/days/years until they don't and melt/start a fire, and then my home can go up in flames while myself and my family are asleep over something as trivial as a loose connection.

Minor correction: power tool woodworking is indeed scary as all shit, very much treat it with respect.

But there is also hand tool woodworking as a hobby. Much less risk. I won't say none (a falling chisel has no handle), but you are much less likely to suffer a life changing injury.

Both, he tried to tell us…

Brian: I'm a **in' idiot because I can't make a lamp?

Bender: No, you're a genius because you can't make a lamp.

Brian: What do you know about Trigonometry?

Bender: I could care less about Trigonometry.

Brian: Bender, did you know without Trigonometry there'd be no engineering?

Bender: Without lamps, there'd be no light.

Breakfast club. Good flick
This is pretty common. If you sit at a desk typing all day, you get home and want to do something physical.
The grass is always greener: Lots of people who work with their hands envy us sitting at our climate controlled desks all day (doing god-knows-what).

Although they do often tell me "oh I could never actually do that, I'd lose my mind". Which of course many of us do :)

My pandemic hobby was dabbling in electronics building synthesizer modules.

You can learn a whole lot about electricity by working on small low voltage projects like that without any risk of harm to yourself.

part of the shop class electrical curriculum, was the initial safety demonstration and hotdog buffet afterward.

https://web.physics.ucsb.edu/~lecturedemonstrations/Composer...

You might find this HN discussion interesting, its full of good explanations for different electrical concepts: https://news.ycombinator.com/item?id=26362492
Yeah I really regret not doing auto shop, wood shop, and metal shop in highschool.