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The best advice I ever got (after my Kindergarten teacher telling me, "Now young man, you should _never_ pass up the chance to go to the bathroom.") was my shop teacher advising:

>Before hitting the switch on a power tool, slowly count to 10 under your breath to yourself on your fingers, visualizing all the forces involved and planning out the entirety of your movement and how you will be moving the stock/tool, and considering what might go wrong and the results thereof and what will protect you (all guards should be in place and all suitable PPE worn) or where you should be positioned so as to avoid any potential projectile, reminding yourself that you want to be able to repeat that count in the same way when the tool is switched off.

Sawstop wouldn't have a business model if all tablesaw accidents were tried by a jury of shop teachers.

I have a similar habit: Before applying power, I manually turn the blade (or workpiece on the lathe) through one full rotation. I also think my way through the entire cut, including where my body and hands will be, and what I'll do if something goes wrong.

I've also mentored younger colleagues. I think there's a problem with shop safety, which is related to computer programming: Some people are able to learn it, and others just aren't. There's a certain situational awareness that you have to develop -- a sixth sense for when something is unsafe, that goes beyond just remembering all of the rules. There's also an intuition that you develop, like in programming, of being able to "think like the machine."

Like it or not, there are people who shouldn't be in the shop.

Pattern recognition. Some people have and some don't. It's also situational for some people.

I had a friend who could immediately see patterns in fighting games, after a few plays they'd immediately know how the CPU would react in certain situations. I could never.

I can see patterns in code, how it relates to other code and in the processes surrounding it, especially when I'm not taking my ADD meds. It's a superpower when shit's on fire and needs to be handled fast.

Similarly some people form this "sixth sense" situational awareness for physical tools and safety. They'll just look at a worksite and "feel" something is off. Or they pick up a tool and immediately know something is off - something in the balance or how it feels in the hand, or maybe it made a noise it's not supposed to.

I ran a small light plastic assembly factory years ago and within 20 minutes of a new person starting I could tell if they could, what I call, “think in 3D” if they couldn’t they would never meet the standard we needed and I’d sadly have to fail their trial at the end of the first day - about 30% of people fell in to this category.

Can you go into detail on this with an example or two? It sounds interesting.

A little bit of a ramble here:

Different mental models is kind of a fascinating thing for me. I don't always pick up on something as quickly as my peers when it comes to things like math and pattern recognition, but I've tended to make up for that with a hard work ethic and what I think of as rabid curiosity and a strong desire to constantly grow my work skill set and knowledge. I've grown a lot during my career as a result when colleagues who had much higher GPAs stagnated. It's interesting how wide and varied our brains are. Again, when doing any pattern recognition games (e.g. speed, set...etc) with my wife...I don't think I'm bad, but she is grasping things at a rate of 3-6x what I can and it was the same in any hard STEM classes that we took together. It's the opposite for things like history where she can't pick up as much of what is going on in a lecture or documentary or whatever. Physically speaking I'm not sure how the brain works differently between us, but I'm guessing the weights are just different if it's anything like the NN in computer science. We were playing dominoes the other day and I had to pause to check which had already been played and she got a little frustrated that I was taking too much time - like what do you mean you don't already know which ones have been played? So I guess it's a greater ability to recognize and retain patterns quickly.

In your case of the worker, I wonder if they were just dangerously clueless or just needed a little more time to build that mental model to grasp how the pieces all fit together. I also wonder how I would have faired.

Sure, difficult to really explain it as I don't think I have the correct physiological knowledge/vocabulary but I can try to paint a picture.

We assembled a plastic product with about 20 components of different shapes and sizes. There were slots to align and friction fit, there were things to click, wires to route, glue to dab etc.

The far extreme of "can think in 3D" were the people who could be shown the finished item, the kit of parts and pretty much just assemble it. They would miss some "trick" or "knack" we had developed and they might not quite get the alignment or placement of a part perfectly but the product would work.

The opposite end were the people who unless I was stood with them and helping to move the components in to alignment just simply couldn't "get" it. It was as if they didn't have a the ability to retain the finished view and movement through 3D space required to complete the movement. Could also have been a coordination, dexterity or proprioception issue.

Of course this was a spectrum and we had to make a judgement call (often in discussion with them) about how they would improve/get up to speed or if it was a lost cause. We built jigs and tools to help remove the finesse required in the assembly which helped a lot BUT, when you got someone who could just see it no amount of training or jigs could get everyone to that speed.

On quiet days we would have little competitions on certain stations to see if people could get a new record and it was those days when you could really see the people who just got it. The best example I can give was making the final cardboard packing boxes, this was an 8 movement process from flat box to assembled with lid open, the record was 2.7 sections, a sustainable pace (so the time that actually mattered) was around 7 seconds, people who just couldn't get it were over 30 seconds and usually with many quality issues as at those people were often fighting the box and material.

Thank you. That's helpful! I find this interesting as well. Some folks like to build with detailed instructions and others prefer to just get the gist and figure it out for themselves. :)

The best math professor I ever had was a fantastic instructor because he had in head a catalog of wrong mental models and could nearly immediately grasp where a student might have taken a wrong turn and try to get them on the right path.

(It was a graduate level real analysis course, and people who had been calculus whizzes were struggling with point set topology proofs.)

Wow that sounds like a real superpower in that setting. I have met many that have very strong visualization/conceptualization skills in things like 3d, mechanical, color/looks, code and electronics - but for other peoples mental models that one was new to me. The closest I can remember would be some sales people I met who are also chess players, they could "play" in their heads a range of different scenarios of interactions in a sales conversation - many levels deep. And would do it, especially if/when stakes where high. In the blink of a second. It would take them muuuch longer to just answer me a few questions on why they thought "C" was the best way to open, and then make sure to get in point "E" (or "G") before proposing "K".

The last one you mention is something I think I have but haven’t thought of it like that.

As in, I’ve many times stopped a friend who’s using a tool because I can tell the sound is off - almost always finding something amiss.

Or picked up a tool and felt that something was wrong.

Same with small engines, the sound and vibrations I’ve always found easy to tell if something is off.

On some level, I thought everyone had this if they spent a few moments around these items.

I realize that is such an ignorant take on my part!!

Conversely, I have almost zero talent for easily telling if code is off, or for fighting games, or numeric patterns beyond basic examples.

I’ll notice things that might be off on my car, but I am far from a mechanic.

When then there is indeed something wrong, I have a hard time convincing mechanics and techs that there is an actual issue.

It’s a heck of a lot easier when it’s your professional domain, and you carry the acumen to back up your findings.

The same applies to firing ranges, scuba diving, etc. too. I'm not from the US but have some firearms experience before moving here. When I was learning shop from my father, or how to handle firearms the core messaging was very similar. Everything you said about the situational awareness and intuition aligns with my experience.

There are many people who can do the main activity (shoot down a range that is clear), but can't setup safely, or muzzle sweep folks when they're asked to step away. These are the really critical situations where you need to be ready to safely do the activity or safely transition to the next thing (which might have its own unique dangers.)

>There's a certain situational awareness that you have to develop

The term you're looking for is executive function and in a nutshell it's the brain watching and controlling the brain. There are deliberate, methodical tasks in which executive function is a great predictor of safety and success. Wood shop is one of them. There are also flowy, improvisational tasks where a lack of executive function allows one to be in the moment and respond quickly to changing conditions. Off the top of my head I'm thinking of a jazz drummer or an freestyle rapper, someone who has to move quickly and guess a lot without much assurance of the results of their actions.

I also wanna throw some support behind the idea of "thinking like the machine". Us coders have a lot of weird little quirks but one that's stuck out for me ever since I read it in the jargon file back in the 90s was the tendency of people who are good with computers to also anthropomorphize them. Most people speak in terms of what computers are programmed to do and what they require, but all the best coders I know speak in terms of what the machine is trying to do and what it needs. The anthropomorphization seems to engage empathy, and that empathy leads to a deeper understanding.

I touched what I thought was a stationary wheel on a lathe as a child. it was of course under flouro tube lighting: it was synced to the tube, the strobe effect made it look stationary. I've never forgotten it.

The guy owning the lathe made some short, sharp observations. But I also suspect he sweated blood later on. Explaining his role in this had I lost a finger or worse would have been nasty

> it was synced to the tube, the strobe effect made it look stationary.

Why is it synced like that? Seems dangerous, and I don't know much about lathes but lighting synchronization doesn't seem something that would affect the mechanical parts being processed :)

> Why is it synced like that?

Synced to the AC mains or a multiple thereof.

Layman's guess: Both were synced to the mains frequency.

This

Sounds accidental, but might be interesting to be able to see the workpiece as if stationary, while it’s turning at 1800rpm. Everything looks smooth under ordinary lighting.

My high school woodshop teacher simply showed us his short finger. Lost in a table saw. We got the message.

I don't get that advice from the kindergarten teacher. Can you explain please?

A lot of young children will have accidents because they forget, or don't want, to go to the washroom. That's true even if it is urgent. (They either don't know what their body is telling them, or they are fearful of washrooms, or they are simply having too much fun to be bothered by what their body is telling them.)

Its simpler than you think:

No one really regrets going to the bathroom when it isn't urgent.

Plenty of people regret waiting until it gets urgent.

Reminds me of when I interned as a medic. My instructor gave me a list of rules:

Walk, don't run.

Never trust the public in a vehicle.

Always check the rigging yourself before rapelling down the embankment.

Sleep when you're tired.

Eat when you're hungry.

And never, I repeat, NEVER wait to pee.

When you live in a world where you may have to scramble at any moment, and you work 72 hour shifts, you can't take simple things for granted. We might go from chilling on base to not being back for 15+ hours.

I remember my biology teacher telling me of the dangers of being a car crash with a full bladder - yet another reason to go.

If something unexpected happens and your saw kicks a board back at you, you don't want to piss yourself as well as screaming

Think before you act.

Take your by own advice ;)

Don’t pass up a chance to pee is the advice in question.

Which I’d equate to; Better safe than sorry

There are enough shop teachers out there with missing digits to prove this statement is not true.

How many of them sued someone else with the assistance of a personal injury lawyer?

While I was lucky to have shop classes in my school, this curriculum makes me extremely jealous, to be honest. We didn't have neither welding, nor forging, nor working with fiberglass composites nor "big" projects, had to learn it all by myself. Still, those classes taught me the basics of actually doing something with my own hands, which is pretty important.

I also remember that we were trusted to behave like adults in front of heavy machinery like routers, circular saws and lathes. No incidents whatsoever aside from minor cuts, which is normal. We were genuinely interested and behaved accordingly, nobody wanted to get hurt and / or get kicked out of the class

P.S. Not sure of how it works in the US, but we also had "shop classes for girls". The curriculum for those consisted of the basics of cooking, baking and working with fabrics (starting from sewing two pieces together in grade 5 and gradually evolving to designing and sewing clothing for yourself by grade 9). Though, in my opinion, those things shall be taught to everyone, not just girls

I had “agtech” in HS. Learning how to use a cutting torch and weld was the most memorable. Heh our welding unit was pretty much all about working on our teacher’s horse trailer. We also did hunter’s education which spent a lot of time on gun safety and was very useful. (Yes, I went to HS out in the sticks)

The latter class would have been called "Home Economics" ("HomeEc") back in the day.

Both these (sløyd /woodworking, heimekunnskap/cooking and home economics) were mandatory for everyone in Norway back in the nineties(although to be fair shop time was limited to wood, we weren't allowed to use metal lathes etc anymore), as was sewing (both with hand and machines).

I'm still thankful because of all the stuff I can relatively easy cook, fix or make thanks to those few hours in school.

(I'd also say they made for extremely welcome breaks between boring stuff in other subjects and being bullied during breaks.)

Still mandatory in Finland.

They have "soft materials" (fabric, sewing, knitting) and "hard materials" (wood, metal working, 3d-printing etc).

In upper classes they have cooking and more of the same.

My highschool had one of the few county vocational schools attached to it. We had things like construction tech, auto tech, PC repair (got your A+ in that class), networking (you get a CCENT), engineering drawing and basics, criminal justice, cosmetology, and what was essentially preschool teacher class along with many others I don't remember. Other schools in the county had different classes but ours was the biggest. The engineering classroom was my adhoc homeroom and the place I spent most days after school my senior year due to joining our FIRST robotics club. We had everything for doing woodworking but also had an old Bridgeport mill, a CNC router (I was the resident mastercam X expert) and a lathe. We did just about all of our robot fabrication there except for the TIG welding (local shop did it for free). The engineering drawing class also had a small woodworking shop too. Our engineering teacher taught freshmen at the local university so we came out of his classes being thoroughly prepared for college.

I bailed on my mechanical engineering major sophmore year and switched to computer engineering. I love building stuff with but just didn't enjoy statics class.

Bonus pic: our 2010 FRC robot "hanging out" after the match: https://www.chiefdelphi.com/uploads/default/original/3X/8/b/...

For all the focus on STEM education in the past couple decades, I'm surprised cooking never really came back in vogue. Cooking is applied science that we have to do every day. I had to figure it all out in my late 20s, because shop and home ec were gutted in the 90s in my district.

I entered junior-high school (as it was then called) in Pasadena, California, in 1969. In seventh grade, all of the boys took four 10-week modules: electricity (make an electric motor), print shop (typesetting by hand and printing with a platen press), wood shop, and drafting (pencils and straightedges). The girls took a year of home economics; my two older sisters learned how to sew in those classes, and one made most of her own clothes when she was in high school.

The next year, the classes were made co-educational, with students choosing which stream to take, but at least in that first year the gender divide remained sharp. I chose to take drafting for all of eighth grade; there was only one girl in the class.

I can’t say that what I learned in those classes paid off for me directly, but I did pick up knowledge and skills that I applied indirectly in my later careers: from printshop for writing and editing work, and from drafting for learning how to use drawing and graphics software.

It would been nice if I had learned how to sew and cook then, too.

In middle school we could take Industrial Arts, Home Economics, and Art. Seventh graders took all three, so they were each 2/3 of a semester, with one of them broken across the semester break.

In eighth grade we got to select two of the three, and they were each one semester. I took Industrial Arts and Home Economics because the Art teacher was a complete wacko who in the seventh grade class destroyed any interest I had in the subject.

I am pretty sure seventh grade Industrial Arts was co-ed and everyone took it. But maybe girls had another option, I don't quite remember. In eighth grade since it was an elective, it self-selected to almost entirely boys.

I had to take either home ec or shop in high school. I’d already done all the shop stuff I’d wanted to while growing up helping my dad make things, so I took home ec instead. I was one of two boys in the class. It was awesome. We baked. We sewed. We hung out with a roomful of girls. It was one of my better high school decisions.

A basic education should include a lot of stuff you never use. If you're not exposed to things that don't interest you, how are you going to find the ones that do?

My shop classes paid off handsomely for me. I recommend taking them.

Did a lot of the same in middle school in the late 1970s. Less of the home repair stuff, and no welding or machining.

We used hand tools and small power tools (hand-held drills and sanders), and drill press and scroll saws. Only the teacher could use the table saw, planer, and jointer.

One kid made a muzzle-loading rifle as his project. Can only imagine the hue and cry that would cause today.

I was in middle school in the 1990's, in Canada so the legal bit wouldn't be all that different from the US. We had welding, machining, and all sorts of power tools. That said, the teacher used their discretion while deciding who could use the more dangerous tools and supervised their use carefully.

Attended an elementary school in Canada in the 80's. There was a shop trailer that went from school to school. It had all the wood working tools like band saw, or drill press. My parents still have some of the items I made in it.

i went to middle school starting in ‘98 (7th grade). I used a hand saw, glass cutter, sandblaster, and drill press. That was just a quarter. The second quarter we had home-ec. Stitched and baked and maybe something else. In shop I made a book shelf thing and a nameplate (sandblasted mirror)

In 9th grade I used a jointer and a band saw, built deep bookshelf out of poplar. In 10th grade I built a night stand (used shaper, Joiner, jointer, etc..)

The table saw was off limits in every class I remember, but most the other things were usable. With saw stops available, I think that reduces liability quite a bit.

Also in high school I did drafting and cad (2D and 3D).

Anyway, that was across 3 school districts in two states, and was as recent as 2003 - so it’s not like shop/industrial arts stopped being a thing 40 years ago.

> it’s not like shop/industrial arts stopped being a thing 40 years ago.

Unfortunately, I live near two school districts - one in a major metropolitan area in the US - which have closed down shop classes in the name of preparing students for college instead of work in the trades. It is hard to undo those decisions.

Fortunately some local “industrial arts” departments continue to thrive.

Yep. I remember going to one of my kids' concerts about 12 years ago and the guest musician mentioning how happy he was to be there because so many schools were closing their Music programs. Same thing is happening to shop class. At least here in a rural district, there's more pressure to keep it going since a lot of what the students learn has immediate use (or they already learned it at home).

Wow, I wish I'd had this.

Closest I got was building theatre sets. But they were some awesome sets, with huge moving parts counterweighted via airline cable and sandbags, and we conceived and designed it all from scratch under very little supervision. Come to think of it I'm sure it wouldn't fly these days (I remember a substitute teacher walking into the gym flabbergasted at one point when I was climbing in the rafters drilling anchor holes for pulleys... the regular guy knew well enough when to be present and when to stay away).

I didn't have access to heavy machinery or welders until high school (14-18), but I was very fortunate to go to a high-school that taught most of the above while I was there in the late 2000s.

The "product design" class (which was really either woodworking or metalworking depending on which stream you ended up in) was definitely my favourite class, and I think the most useful for later life too.

My step-father taught shop for over 30 years at the 7th-9th grade level using all the tools you mention. I can't recall a single serious accident under his watch. Not to mention, at his funeral, you'd be shocked at how many of his former students came to pay their respects. Many talked about how it had changed their lives irrespective of the fields they worked in as adults.

Further not to mention, I'm sitting next to two Appalachian dulcimers that were among the 100s he built in the 70s and 80s.

My old man taught shop at the high school level for a similar amount of time, and (even though I am admittedly biased) I can say that he was measurably the most beloved teacher in the school. To this day, he gets messages from former students who are now successful tradesmen, thanking him for getting them on the right path.

Similar experience in Portugal, between 10 and 18, that is why when I got into university already had a couple of years experience in metal and woodwork, electricity, and computing in general, enough to get a job if my application had fall through.

> In today's world, parents (and lawyers) might find it unsafe for boys (very few girls elected to take these classes) but in seven years of shop, I only recall one serious accident involving the loss of a finger tip.

A lot of the danger can be ameliorated by using CNC machines instead of circular saws and hand lathes. Standing 3-6 feet away from the machine when something goes wrong is way better than being 3-6 inches away.

Gantry CNC machines are superior to table saws for almost all sheet goods, anyway.

Sure, the jointer is still kind of dangerous. However, it has a very specialized function and normally you can keep your hands safely away from the blades with various push mechanisms.