(Updates from the Workshop)

Junior Engineering (1976)

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March 30, 2020.

While most of these Updates from the Workshop are just that - project accounts - this is not. Instead, this is an entirely personal recollection of two extraordinary shop classes that I had in Junior High School. If they weren't unique they were close too it; Google knows nothing of them. They deserve not only to be remembered but to be revived.


In California when I was a kid (even now I hesitate to say "grew up"; I never got the hang of the growing up bit) school was divided into what seemed a perfectly logical trio: Elementary school from grades 1-6, Junior High School from grades 7-9 and High School from grades 10-12. The classes I'll describe here were ones I took in Junior High School. That would have been the 1974-5, 1975-6, and 1976-7 school years, and I would have been ages 12 through 14.

This all happened at Bret Harte Junior High School in San Jose, California. Like Star Wars, which came out then, it was a long time ago in a galaxy far, far away.

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Drafting & General Shop (7th Grade)

Before I could take the two classes which are the main subjects here, I had to take two preliminary classes.

The first of these was 7th grade Drafting. It was taught by Mr. Paxton, a fine teacher who (in my mind at the time - I was only 12) had the great misfortune of having the same surname as my orthodontist. It covered straightforward 3Q 20th century simplified drafting practice. (We're not talking wash renderings for the École des Beaux Arts here.) It was straightforward, yes, but was still a supporting technology capable of "landing a man on the moon and returning him safely to the Earth" (as Kennedy had said, only 13 years earlier). This was the high point of my entire 24 year academic career: I got an A+ on every single assignment. It was downhill every step of the way from there to my Ph.D.

There was no textbook for this course, which was just as well. I collect drafting books now, and on review it is clear that their quality took a nose dive in the 1970s. If you want to learn drafting, get the 1940 second edition of Giesecke.

In the 7th grade we also had a decent shop class (not exceptional by earlier standards, but unheard of today). We didn't have a proper machine shop, but at least there was a shop. This class started with basic hand and power tool woodworking (making an hors d'ourvre serving tray and a tool tote). Then we did some simple sheet metal work (a tool tote in bent metal) and some very simple hot metal work (not proper blacksmithing, but heating and bending metal in a gas forge and hot riveting).

Here are the wooden and metal tool totes. The metal one is hot riveted. They aren't much to look at, but they're both still in use in my shop 46 years later.

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So far, this is all good stuff to have done, but it wasn't extraordinary for the time.

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Architectural Drafting and Model Building (8th Grade)

Now we come to the first of the two very special courses.

They were both taught by the shop teacher, Mr. Barrett. (I'm not entirely sure I've spelled his name correctly. On the one surviving architectural drawing set where I have it recorded, I spelled it with one 't'. I'm assuming that I made a mistake then, but I'm not sure. He might have been Mr. Barret.) I recall him as being very tall and very calm (both useful attributes when dealing with Junior High School students).

The 8th grade class was titled, accurately but awkwardly, "Architectural Drafting and Model Building." In it, we first designed a house. We drew it to current architectural drafting standards, including such things as foundation structural details. We made whiteprints of our drawings ("blueprints" were by then an obsolete technology; whiteprints were white-background, dark-line diazo process prints).

Here are the original Sheet 1 (floor plan) and Sheet 3 (foundation plan and section), both drawn in pencil on drafting vellum. The date is 2/24/76 (that is, 1976-02-24 in the unambiguous ISO 8601 format). Looking back on them now, I'm pleasantly surprised at how good the foundation section looks. Not bad for a 13 year old kid with a pencil.

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Then we constructed a section of this house as a resonably accurate 1/12 scale model. My house design was 31' 4" square, so the model shown below is 31 1/3 inches in its long dimension (outside wall to wall, excluding eves).

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By "reasonably accurate," I mean that while it wasn't as if we used a science fiction shrinking ray to miniaturize a full-size house, we did use authentic methods and materials of construction in miniature. We poured a scale-sized foundation of real concrete (using plastic screen material inside the concrete to keep it together). The footers didn't go down very far, but this was coastal California, where they don't know about things like the frost line. Here in Wisconsin such a foundation would not do. Then we took scale boards (resawn out of larger pieces of wood) and framed the walls and rafters. We used brads to emulate real (scale) nails. We put in bits of real fiberglas insulation to show where it would go. We laid scale wood shingles for the roof. My house had a stucco exterior, so we put up stucco for a section. If you had wanted to, you could have used any of our models as a teaching aid to show new tradespeople how a wood framed house was constructed.

(And I still know how to frame a wall, which is a skill that has come in useful here on the farm.)

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I tend to overdo things. It's an old, bad habit of mine. So my house model went beyond code in two instances. First, the building code in California, then at least, required "firebreaks" to be placed in the walls between studs at certain locations (but not between every stud). These are just horizontal boards put in to slow the fire - keeping it from just going whooosh up between the studs. I put them between every stud. I also went beyond regular rafter framing and used W-trusses (which are very strong).

(You can see the firebreaks in the photos above. The W-truss is shown in the photo below left. The photo below right is the crawlspace, complete with authentic debris. I've never liked crawlspaces.)

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The upshot of these "improvements" was that Mr. Barrett decided to test my house model by standing on it (not a part of the formal course requirements). It held up just fine. By way of scale, and making no implications about his physique, this would be like building a real house and inviting King Kong (from the 1933 original film) to stand on the roof.

Like so many things one makes when one is young, this ended up getting stored by parents. I was delighted to discover, many years and several parental household moves later, that both the drawings and the model survived. Thanks, Dad.

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Junior Engineering (9th Grade)

It was the 9th grade class, though, that put this whole experience over the top: Junior Engineering.

There were four projects: the bridge, the car, the rocket and the balloon. For reasons which will become apparent, only one of these survives to be illustrated here. I like overdoing things, and I overdid these, each in its own special way.

The Bridge

The bridge didn't have to look like any real-world bridge. This was an engineering project, not a modeling project. It had to span a certain distance (three feet, if I recall) and bear a certain static load (I can't recall how much). The requirements were framed such that you had to build it up as a structure - just laying a 4x6 inch timber down wasn't acceptable.

Mine was generally inspired by the Sydney Harbor Bridge, with some changes. (It's made of wood, for one thing.) In addition to making laminated longitudinal members for the arch, I used the roadbed to tie the arch together. Having seen the classic film of the Tacoma Narrows Bridge, I rather overdid the truss of the roadbed.

Here's what survives. As built, it had overly heavy concrete piers at each end with a short tunnel through each pier.

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It was never as pretty as the real Sydney Harbor Bridge, of course.

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(Photograph of the Sydney Harbor Bridge by Wikimedia Commons user Adam.J.W.C., 2011-12-30. License: CC-By-SA 2.5 Generic. Source: https://commons.wikimedia.org/wiki/File:Sydney_harbour_bridge_dusk.jpg)

Having tested my house model the previous year by standing on it, Mr. Barrett could not resist the temptation to test this one in a similar fashion. No problem. (Or, since it was based on an Australian design, perhaps I should say no worries.)

The Car

(This and the rest of the Junior Engineering projects would be better with pictures. But I didn't have a camera then and nothing survived, so you'll have to make do with words. If you're under 20, think of this as a podcast that you read.)

The car project brought out another of my bad habits (one which would have gotten me into a lot of trouble if I had really become an engineer): that of reading the rules ... opportunistically.

The "car" was a small four-wheeled toy or model vehicle that you built mostly out of a block of wood. It wasn't steerable, but rather it traveled on two little eye-hooks along a long wire strung tightly from one side of the shop to the other. The fastest car down this measured track/wire was the winner.

The car was actually jet-propelled, driven by the gas escaping from a small pressurized carbon dioxide cartridge. These are still commonly sold for use in things like airguns and kitchen gadgets which make Fizzy Lifting Drink. Mr. Barrett had built a small device which punctured the business end of the cartridge and then off the car went.

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(Photograph of CO2 cartridges by Wikimedia Commons user Hustvedt. License: CC By-SA 3.0 Unported. Source: https://commons.wikimedia.org/wiki/File:BB_gun_with_CO2_and_BBs.jpg)

It was obvious to me that the trick to this was that the rules said nothing at all about the car after it crossed the finish line.

So I carved away the body until there was just the thinnest skeleton that would hold four wheels and a cartridge in their respective locations on what was in fact a wire-guided missile. The wheels were, by this time, purely ornamental - it would have gone even faster without them. It worked; this car was the fastest down the wire by a good margin.

Of course, after it crossed the finish line and hit the end of the wire, it vanished into a puff of splinters. The rules said nothing about the car having to survive.

The Rocket

I think that I had the most fun with this one.

It was an exercise in conventional model rocketry. This was (and still is) a vibrant field (and the people who are seriously into it have some extraordinary knowledge and abilities). It is also a field which, at the hobby level, has some commercial support. Estes Industries has been building solid-fuel rocket "motors" for decades. Here are several of their motors:

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(Photograph of Estes model rocket motors by Wikimedia Commons user Cassavau. This person has dedicated this image to the public domain under the Creative Commons CC0 1.0 Universal Public Domain Dedication. Source: https://commons.wikimedia.org/wiki/File:Estes_Model_Rocket_Motors.jpg)

In the image above, the second motor from the left is a model C6-7. The 'C' indicates its relative size. The 6 tells you how long the rocket burns (in seconds). Then there is a delay of 7 seconds before a charge ignites in the opposite end to eject the parachute. We used C6-5 motors.

The project requirements were straightfoward: using an Estes C6-5 motor, build a rocket any way you wished so long as it got its payload up to a certain height and returned the payload safely to the ground. The payload was a blown egg (just the eggshell, intact except for small holes at either end, with the contents blown out).

I've always liked to research things, so I checked out the only book on model rocketry from the public library (yes, there was one). I'm pretty sure it must have been G. Harry Stine's Handbook of Model Rocketry. I proceeded to design and build what was really a very conventional model rocket - except that I encased the blown egg in a carved-out balsa wood casing to protect it from shock. I'm pretty sure you could have just dropped it from altitude and the egg would have been ok.

This flew very well, but that's not much fun.

As we had some time and I'd met the requirements, I got a chance for another flight. For this one I built a new nose cone which was just a long streamlined point - it looked much more like a missile now. (But I left the rocket's fins just the same.) This, too, flew well.

So I had time for yet another flight ... but here I need to interject a bit of actual rocket science. In a rocket flying in an atmosphere, there are two points of critical concern. The Center of Gravity is the point where the rocket "thinks" it is; it's the point around which the rocket would balance. The Center of Pressure is the point where all of the aerodynamic forces on the rocket want the rocket to be. For positive stability, the Center of Pressure must be behind the Center of Gravity. It's like pulling a trailer vs. pushing a trailer (sort of; this is a rough analogy): If you're pulling a trailer, then all of the influences of the road and wind and whatever on the trailer (that is, the trailer's Center of Pressure) are behind your vehicle (which is, roughly, the Center of Gravity of the system) and things are stable. If you try pushing the same trailer in front of your truck, things don't work so well. (This also explains why backing up a trailer really is rocket science.)

So for this final flight I fitted a little stub nose cone (but left everything else the same). Now my rocket, which had been designed to be aerodynamically correct with a great big egg-carrying armored nose, had nearly no nose at all. The center of pressure remained pretty much in the same place, but the center of gravity had shifted much further back (almost certainly behind the C of P). The rocket was now radically unstable.

Its final flight was a chilly morning with a very low overcast - not more than 100 feet at most. The rocket left the launchpad at about a 45 degree angle and disappeared into the low clouds. It's not really clear what happened then, but a delicate rain of small bits of rocket fluttered down out of the clouds over a pretty wide area.

That was fun.

The Balloon

The final project was a hot air balloon. This was a team project. My partner was a really nice kid from India.

Again, the rules were simple: make a hot air balloon (heated by the air from a Coleman camping stove). The stove stayed on the ground (the balloon didn't have to have a heat source on-board). All the balloon had to do was fly.

Tissue paper and glue were the suggested materials. The easy solution (which everyone else used) was to make a big tissue cube or box. Trouble is, I thought, this didn't look much like a proper balloon. Balloons ought to be spherical.

Recall that this was 1977. Pocket calculators were pretty new (and expensive). But my dad borrowed a very simple calculator from his work and let me use it in the evenings. With it, I calculated enough points to define the curved shape of a spherical balloon gore (and also the weight of air over a range of temperatures and the estimated lift of our balloon). We plotted the gore calculations on cardboard as a template and cut the tissue paper to match.

I don't recall there being any requirements for how high or far or long the balloon had to fly, but ours simply rose up and drifted out of sight. We heard rumors later of it being spotted a couple of miles away. We never found it.

I still wonder what would have happened if I had put some aluminum foil on it. During this period the radar tower on Mt. Umunhum (Almaden Air Force Station) was still in operation. I didn't, which is probably just as well.

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So What?

Why is this important? It was fun taking these classes, but that was a long time ago and you weren't there. (If you were there in Mr. Barrett's classes, please let me know! It would be good to record other experiences with them.) It's also been fun remembering them here and, yes, bragging a little bit about my old projects. But none of this is of any general importance.

Mr. Barrett's Junior Engineering class, especially, is important today because we should still be teaching it now.

In it we made things that were strong, that went fast, and that flew in the air. I put it to you that these activities remain appealing. (Marvel/Disney have grossed more than 22 billion dollars selling these three characteristics plus a superhero who is a maker. Even if you don't believe me here, money talks.)

In it we used only common materials. The most exotic items (the CO2 cartridges and model rocket engines) are still readily available. Everything else was wood and tissue paper and glue and hand tools. You can do this.

It involved making, and allowed it at whatever level of engagement you wanted. Sure, I geeked out and calculated a spherical balloon, but the kids who just make a big tissue cube still got the satisfaction of seeing something they made fly for real.

It was hands-on science, below the radar. There wasn't a heavy theoretical side. No math or equations required. But you got to see how things worked (or didn't) in the world. The science hasn't changed. The principles of statics are the same in 2020 as they were in 1975. So are the laws of acceleration, of centers of gravity and pressure, of buoyancy. Mr. Barrett taught by showing and we learned by doing. This never gets old.

The last quarter of the 20th century was a grim period for education in America (I had a front-row seat, watching California willfully destroy what was once the finest educational system in the world with Proposition 13 and its effects. The educational opportunities then available to me, including college without tuition, are gone.) But we've come a long way back in the last few years. Hands-on technology in the classroom is happening again, though I suspect that "shop" remains a four-letter word. The Maker movement has helped a great deal. But we still haven't recovered to the point we were decades ago. Mr. Barrett's classes -- classes taught by the Shop Teacher -- remain important because we should be doing them today. We should start with what he did, because it worked, and extend this to new projects and new ways to learn science by hand. This is relevant to every school, educator, and makerspace in the world. Yet so far as Google-the-all-knowing can tell me, this is the first time that these unusual and inspiring classes have ever been recorded.