The 70s really were another country - see also: chemistry sets. These are pale and anodyne things now with a mere handful of bland household-level chemicals - assuming you can even find one in a toy shop at all. But as a lad these were both readily available and full of dozens of intriguing substances that would send a modern health and safety wonk into apoplexy. Who among us did not incinerate all of the supplied magnesium in a short series of pyrotechnic orgies? Merit was the go-to brand in the UK, but I also had a set from an American company that contained, among other exotica, potassium ferrocyanide. This is decidedly non-lethal but the very name never failed to send a poisoner's frisson through my teenage brain.
Those sure were different times. I recall in the mid 1970s, as a kid no less, being able to go into a pharmacy and buy sulfur or KNO3 w/o any trouble at all. However it wasn't more than a couple years later, when a request for phosphorus was met with an icy "do I need to call your mother" stare, that my budding career as a chemist came to an end. Besides, the Radio Shack across the street had this computer set up for customers to play with..
My friends and I found documents authored in the 70's and went around the 90's trying to buy saltpeter--whatever that is. Luckily time had changed "Do I need to call your mother?" into "What the hell is that?" and our mothers were never called.
We eventually gave up and graduated to shoplifting model rocket engines, which we powdered with vice grips.
Can't even buy 30% peroxide anymore over here :/ Some regulation, some scare mongering and it only got sold to business customers... I can do that, but the quantities are also business-sized, and I don't need 20 liters of peroxide, but can't buy it in 1L bottles anymore
Sulphur? My local hardware store sells flours of sulphur for gardeners. It's used for acidulating soil, and for combatting some kinds of fungus. I don't know why anyone would want to regulate the sale of elemental sulphur; it's not toxic, caustic or explosive. It's less flammable than a piece of wood.
I would collect sulphur - good quality from near the railroad tracks as small amounts would inevitably bounce out onto the ground from large shipments going by.
So regulate charcoal. And black powder requires saltpetre, and doesn't require nitric acid. You can make saltpetre from piss, but I don't know how.
And is black powder so scary? You can get it out of firecrackers, which are sold (here) without ID, although I guess you might have to prove your age to buy fireworks. It doesn't detonate, so it can't be used to prime a high-explosive like ammonium nitrate fertilizer.
Saltpetre was available from chemists (ie pharmacies) in the UK, but me and my pals had limited success making decent gunpowder with it - I strongly suspect it was heavily laced with some form of fire retardant precisely to thwart pyromaniacal little herberts like us.
Its still sold in the UK for certain culinary purposes, surprisingly enough.
As for why your experiments weren't as spectacular as you hoped: the particular charcoal you use is really important. Its best to make your own with a paint can, some willow, a nail, and a campfire.
Adequate crushing of components into floury powder follows, then adequate mixing, and ideally wet-pressing and corning.
The potassium salt is sold for curing meat from a fair few somewhat specialist providers in kilogram amounts, or in small bags from a fair few shops catering to Eastern Europeans.
Its actually quite fun to read the labels on stuff when browsing shops, you find all kinds of bizarre shit.
For all the broke young thrill seekers still out there and reading hn, KNO3 is readily available as "stump remover / killer" (for which it's ... better than placebo) and dirt cheap since it's technical grade
Stump remover is cheap and plentiful. I tried to make gunpowder with it but it was not what I hoped. (It fizzled and went out).
What I did have more success with is smoke bombs. Mix sugar and KNO3, heat up slowly in a non-stick pot until molten, pour into appropriate molds, let cool and ignite as desired.
Who among us lit up the chunk of sulphur and (out of innocent curiosity) took a good snork off it, realizing too late that it was a stupid thing to do ? I sure did.
Tinkering with chemistry also motivated me to look for sources of hydrochloric and sulphuric acids, but in New York state the guy at the pharmacy said I needed parental permission. Wasn't gonna happen.
Hydrochloric acid: My hardware store sells 30% HCl as Spirits Of Salts, for removing limescale from toilet bowls. It's effective, unlike toilet bleach. It's nasty stuff, and if your seat-hinges are metallic, you risk corrosion. And remember to flush before you crap.
Sulphuric acid: No, hardware stores don't sell that here. You can get it from car batteries, and builders use the strong stuff for clearing drains. I have no idea how I could legally buy fuming sulphuric acid.
Nitric acid: Even less. Fuming nitric and sulphuric acid mixed gives you nitrating acid, which in turn is the gateway to nitrocellulose (and I suppose nitroglycerine), fulminate of mercury, and ghod knows what.
It's just as well that these latter two acids are restricted; if they weren't, I'm quite sure I'd have tried to make guncotton, and probably blown myself up.
Where do you live? If you're in the US, check if you live near an Ace hardware store; mine sells gallon jugs of 90% sulfuric acid for something in the range of $25. Look for Rooto brand drain cleaner, and if it doesn't say on the side of the container, you'll want the one that feels like it's full of heavy viscous liquid.
And Duda Diesel sells a liter of 67.2% nitric acid for $60.43, or $101.69 for 2.5 (plus shipping ofc).
I had the same idea when I was in school, and wrote a chemical company I found in the yellow pages for a price list and order form for Sulphuric and Nitric Acid.
The happily provided both... with a minimum order quantity of around 250 gallons.
I ended up with a fair bit of unusable glassware after a week or two. Fortunately we had a whole kitchen full of stuff. Bad idea. Lots of pocket money got docked.
My friend had a chemistry set that included a lead bar. We liked to chew on it -- imagine, a metal soft enough that you could easily dent it with your teeth!
The really old ones from the 50s and 60s were magic, and they still made passable ones into the 90s. But there is nothing like that anymore, it simply doesn't exist. I suspect that market is now tinkering with Raspberry Pis?
I remember, when young, I would always find these old chemistry sets for sale at garage sales around my grandmother's neighborhood. Parents didn't really care, so long as you didn't destroy / damage anything!
Really? I remember us having problems buying magnesium ribbon back then. A friend got some from our chemistry teacher with a bogus reason. Unfortunately, the thermite mixture wasn't done right--pebbles rather than powder--and it didn't get going.
Something not mentioned is that these things were pretty messy. At least mine was. It burned a mixture of oil and gasoline, and the plane got coated with a film of oil.
I only used mine a few times. I found it rather tedious just spinning around in place. Much more exiting were the model rockets that used solid fuel engines.
Back in the day, you were allowed to bring ESTES toy rockets in hand luggage... I'd guess today they'll put you into prison just for bringing them to the airport.
There was a concern about starting fires when they came down. I heard the rocket club at my school had to notify the fire department beforehand.
I just remembered I also had a gas engine helicopter. Much more fun since it was free-flying. It would go pretty much straight up then rotor down when it ran out of gas. Couldn't do it on a windy day.
Those helicopters were very difficult to fly, or so I've been told, as they were unstable. The modern electric copters cheat because they use a computer to stabilize them.
Large helicopters are not as difficult to fly as small ones, simply because the time constant of their instability is longer. This is similar to how it is easier to balance a broom on the tip of your finger than a pencil, and a pencil is in turn easier than a toothpick.
It's possible to build a passively stabilized helicopter and a lot of modern model helicopters use that method. You can even get away with two axis control!
The fun thing to do with the engines was to start them standalone, point them straight up and let go. They'd go shooting up into the sky until torque reaction made them spin fast enough to stop fuel getting to the engine - at which point they'd pop and misfire, and tumble back to earth (sometimes restarting on the way back down.
To this day I have scarred fingers from playing with these model engines.
We had that in helocopter form. You started it (of course hand spinning the prop). It took off, ran out of gas and came back down. There were large blades that slowed it decent.
I remember we first started it, we had no idea what to expect. (the pre youtube days)
Its a wonder kids who grew up with these things have any fingers..
I had a similar experience building model rockets with those Estes brand engines.
After many hours putting together the rocket, I launched it successfully but the parachute got stuck in a tall tree and I couldn't retrieve it.
My Dad an I had the bright idea of simply lashing a bare Estes engine to a balsa rod, and launching it like a classic Chinese rocket. The performance was amazing, so we promptly drove to the hobby store and bought the biggest engine they had in stock. The "D" size, if I remember correctly.
That was a tad too much power -- our contraption bent and started going in spirals and nearly set someone's garden on fire.
We removed the engine from my control line model and made a much more dangerous device! We mounted three wheels on the edge of a Frisbee and mounted the engine vertically in the cut out center. Then we started it and let it uncontrollably bounce, fly, and spin around the driveway, scattering gravel, until it ran out of gas or quit running from sheer abuse.
My dad made something like that, except not with a Frisbee. It had two helicopter blades, and a dowel sticking out opposite the engine for balance. It had a little ring at the center of it holding the other parts together. He'd launch it from a screwdriver through the ring.
And once he did, it was pretty random where it went. Once it just went horizontally at about ten-year-old-me's head height. I ducked under it and it kept going. Sometimes it didn't do that much. And once it flew up... hard telling now, maybe 50 or 100 feet, and traveled maybe 1/8 of a mile before it ran out of gas.
You could sort of steer its initial direction by slanting the screwdriver. After that, you had no control, not even a kill switch.
I'm not sure that device qualifies, but I've often told my wife that I hate the farewell phrase, "Stay safe!" that's become so common lately. Sometimes you have to balance whether something is enough fun to justify the risk of death.
Wow. Way to bring me back. Looking at the link above I immediately recognized a similar toy that I had in the early 90's. it was of a similar design but with a small electric motor, and a stiff wire about 3ft long running to a control box that also had batteries. The UFO would hover. As I recall it was red and looked like a UFO.
If we're talking toys that don't exist anymore, anybody here ever have a water pressure rocket? You'd add water and then pressurize it with a hand pump. They'd go about 50 ft in the air I think. Once by accident I released a pressurized rocket in my parents kitchen leaving a nice dent in the ceiling.
Hey, I still have my Cox 049 engine somewhere. The airplane is gone, smashed up of course. I suppose it was dangerous by modern standards, but not at the time. About the worst it would do would cut your finger if it backfired when starting. Or you could use a cheater stick, or even an electric motor to start it.
I once made a car for it out of piano wire. It would take off at high speed down the road, but because I never could get the wheels aligned perfectly straight it would inevitably try to turn and flip into a wild crash.
One of the neighbor kids had a free-flying one, that was supposed to fly in a circle. It sorta did, as the circle moved with the breeze, and eventually it broke someone's 3rd floor living room window.
My biggest concern about modern toys is that we have dumbed them down to work for the lowest common denominator. That's why a 3 year old today can (with a bit of training) assemble 12+ LEGO sets.
Back in the day, when I was playing with LEGO Mindstorms, I thought the fact that you compile binaries and flash them with a USB cable was a feature, because it gave you full control. There was even alternative OS choices like [1]. I'm not sure I would have learnt the same amount with the modern version, which is centered around an iPad app with video tutorials.
Similarly, chemistry experimentation kits were amazing - until they started making them idiot-proof and removing anything that could be dangerous if you eat it. Nowadays, as an adult, I need a special permit just to refill the chemicals that I experimented with as a 10 year old ^_^
I have a bone to pick with LEGO. LEGO destroyed Erector sets. Erector sets were great because they were metal parts that you screwed together, and the machines you built look like machines. (My mom was reluctant to get me an Erector set, assuming I could not handle the tiny nuts and bolts. But I had no difficulty with them.)
There is two kinds of Lego (actually, a couple more but for this two will do). Lego bricks and Lego Technic. Lego Technic was conceived from day #1 to make proper machinery possible, the colors you are free to ignore. The old Technic sets such as https://thelegocarblog.com/2011/11/20/lego-technic-8860-car-... this one were really quite nice from a mechanical point of view.
Lego created the technic line because in Europe 'Fischer Technik' (from the factory that makes those plugs to hang stuff on the wall) was eating their lunch, especially in Germany and NL, two major markets for Lego. Fischer Technik was both more durable and far better suited to building machines than Lego and they had a whole line of electronic components to go with it.
Erector sets and Meccano were fantastic too, but not nearly as quick to build with, nor did they stand the test of time as well, clearly Lego did something right in making this stuff accessible.
So Lego did not 'destroy' anything, it all still exists it's just that the markets have shifted considerably and with Lego being heirloom grade plastic some of the bricks that we have here are now in their 6th decade and still being used by my kids.
I haven't thought about Fischer Technik for about a decade. Back in high school, there was a Principles of Engineering class (part of the Project Lead the Way curriculum). One of the projects was to make a marble sorter.
My group wanted to make a continuous belt marble sorter, rather than fully processing one marble then working on the next. Our chute to sort to buckets at the end didn't move very fast though. On the demonstration to the teacher, one of the marbles rolled along the seam between two buckets, only to fall into the correct bucket giving us 100% accuracy. He wasn't impressed with that part, but gave us the grade regardless.
In Uruguay and other spanish-speaking countries those were called "mecanos" (which, judging by other local customs such as calling sneakers "championes" and bubblegum "chicles" was probably a trade name) and they were great. I'm from 1978 and got to play with some sets from my dad (who's from '49). Besides being entertaining, they were a great way to develop mechanical affinity (if that's the right expression in English? I mean things like knowing how far to turn a screw so that it's as tight as it can be but you don't break the piece)
Sadly, you can't get them anymore here, at least not ones good in quality. There are similar building games but they all feel rather cheap and I know from personal experience they only survive a few repurposing of the pieces.
I do love LEGOs though, even though I played with copies in my childhood as my parents couldn't afford the originals. My main gripe with them is the sets. As a child, I just had a bunch of blocks and would build whatever I wanted. Now you can still buy "just bricks" but most of what kids get at stores are sets that tell them what to build. They feel more like 3D puzzles than building games.
Erector-like sets and LEGO-like sets can go together well though: I enjoyed demolishing my brick buildings with my mecano machines :)
In Uruguay and other spanish-speaking countries those were called "mecanos" (which, judging by other local customs such as calling sneakers "championes" and bubblegum "chicles" was probably a trade name)
Take a look at Cobi toys for the less garish models, although they aren't going to be like Technic sets.
I still have my old erector set for my kids, as well as several boxes of knex. When I was young, I eventually lost all interest in legos once I had an erector set and a large enough knex supply.
Those erector set electric motors were downright scary and I have many memories of bruised and cut fingers from making an airplane with a single odd numbered hole bar.
Is that really a bad thing? Minor things like that teach the kids how to handle tools and machinery, so they can operate safely the dangerous tools adults use. Like most boys, I had to learn the hard way to not put my finger in a light socket, and how to not stab myself when the screwdriver slips.
As my professor would say "We learn by doing!" I learned so much from my erector set: about the dangers of spinning objects, how gears mesh, and even seemingly minor things like how frustrating tiny screws and nuts are when you are still learning the required fine motor control.
I took the fine motor control for granted until I saw some young adults unable to get the blade of a screwdriver in the slot, then apply force to keep it in the slot and turn at the same time.
(Maybe that's why people keep reinventing the screw head, so I need multiple sets of screwdrivers. arrgh)
>My biggest concern about modern toys is that we have dumbed them down to work for the lowest common denominator. That's why a 3 year old today can (with a bit of training) assemble 12+ LEGO sets.
I think Lego is the perfect example of this. I never understood the point of it as a kid. Why would I want something that comes with an instruction booklet to recreate the exact thing shown on the box? Why wouldn't I just ask for the thing pre-made instead? And furthermore the bricks were useless for actually creating things. It's nothing more than a slightly more advanced wooden block set.
K'NEX on the other hand was awesome. You could actually build things. Erector too. And those came with all sorts of cool accessories like electric motors and solar panels that you could use to build crazy contraptions. Sad that those things aren't as popular anymore.
There's a sort of zen pleasure in putting pre-designed Lego sets together, especially the more sophisticated ones where you discover along the way the little building tricks or "easter eggs" included by the designer.
Lego bricks certainly aren't "useless for actually creating things." You can make lots of cool things with Lego, and there's lots of creativity to be found in the Lego community, beyond just following the directions.
I do agree with GP that the listed ages on LEGO sets are absurd if taken as difficulty levels. My elementary age kids have no trouble with "18+" LEGO sets. I think the ages instead serve a marketing role: the 18+ rating gives adults permission to buy a toy.
> I think Lego is the perfect example of this. I never understood the point of it as a kid. Why would I want something that comes with an instruction booklet to recreate the exact thing shown on the box?
1) The same motivation as a model kit... except what you build is intended to be played with and won't be (permanently) destroyed by play.
2) Same motivation as a puzzle.
3) Modern Lego instructions do a lot more hand-holding than the ones I had in the 80s and 90s did, so I'm not sure how true this still is, but the ones back then were basically a series of sometimes-pretty-challenging spatial reasoning puzzles. So anyone who enjoys that kind of thing might enjoy assembling Lego sets.
4) Once assembled, you could customize, re-dress, and mash up the sets in ways you couldn't with other toys, and fall back on the directions to fix anything you screwed up too badly, if you wanted to get back to baseline. For example, one of the "good guys" bases from the Pirate series spent more time as a marine research base than it did hosting swashbuckling shenanigans, for me. My big castle sets would grow castle towns from a mix of smaller castle-series sets and custom builds on big flat plates. That kind of thing.
5) You could really destroy a Lego toy built from a set, then put it back together. You couldn't smash apart any bit you liked of an ordinary airplane or ship or castle toy and not ruin it permanently. With Lego sets, you can.
For my part, I've never understood people who don't understand the appeal of Lego sets, because I find the appeal so multi-dimensional and obvious.
[EDIT] FWIW I do find a lot of modern Lego sets worse for some of these purposes than the ones I had as a kid. They've leaned more into the "model" side of things and less into the "play". Exposed nubs get covered up (looks better on a shelf, or on the box photo, that way) so you have to tear pieces off to attach other things to it. Builds are incredibly fiddly and use tons of really tiny bricks even for basic things like a wall, so re-building from memory or a little simple reasoning after destroying a small part of a set is now far more difficult (I suspect CAD run amok is to blame for this one).
The best experience with legos is if you had older siblings who got the legos. Then by the time you got the hand me down legos, you ended up with just a big bin of random parts, no sets, no manuals. I would create elaborate bases or freighter style space ships for playing with my other toys, play with them for a while, then take them apart and make something else. It was kind of like minecraft is with kids today, but with your two hands.
I also loved K'NEX. I built so many things, expanded the Big Ball Factory with additional logic gates at the top, got hands on experience playing with gear ratios, tower cranes, and built vehicles to race against my brothers down the stairs (of course the K'NEX man had to stay intact!).
It was fun building chunks of a big structure and assembling them together, and inevitably having to rebuild a chunk because of some missing pieces.
I do wish they built a control system akin to Lego Mindstorms though. Turning motors on and off manually was fine, but I really would have love to to be able to, for example, build my tower crane such that it could rotate via motor, and have separate controls for lowering the bucket and moving the load closer/further from the tower.
We did our toy shopping at thrift stores in the early 70's and the old Gilbert sets I had as a 10-12 year old were much better (for dangerous values of better) than what's available today.
Oh cool, thanks for reminding me that this book even exists. What's really cool is you can just read it on the internet archive! [1] Almost makes me want to invest in some borosilicate glassware and lab safety equipment, and make a youtube series based on experiments in the book or something haha
I used my chemistry set also to distill wine and drink the results, and for what I recall, it tasted good. Problem is that I was like 12, but did that only a couple times: creating stinking bubbling blobs was a lot more fun.
I liked created smoke bombs using sugar and potassium nitrate. One day, they went off while cooking them on my front porch. I poured some water on it so that any embers that fell between the board wouldn't ignite any leaves or debris under the porch. I mush have poured 40 gallons on it, because it was a cold day and the water was creating steam that I mistook for smoke. Not funny at the time, but pretty funny now. At least I had the sense to do it on a hotplate outside instead of in the house.
> but because I never could get the wheels aligned perfectly straight it would inevitably try to turn
Hm. I don't think "wheels aligned perfectly straight" is the actual solution. I wonder if there's some simple mechanism by which it could be made directionally stable, in the sense of continuously adjusting itself to go forward instead of turn.
You need the center of drag to be behind the center of mass (think “feathers on an arrow” as the mental model). Free castering front wheels with fixed rear wheels that develop progressively more drag as the yaw increases will help, but you’ve got to get the mass forward as well.
I think you want non-castering rear wheels, because you want the side forces to be generated when the vehicle is yawing with relation to the direction of travel. As the sled starts to spin, non-castering rear wheels will tend to oppose the spin. (If anything, you might even want to set the rear wheels fixed and slightly askew [toed-in] to increase the drag while traveling in a straight line [with near-zero yaw angle].)
Angling the wheels slightly outward would at least work to course-correct if the weight of the contraption gets slung out. If the car leans left it'll have the most weight on the left-angled wheels, putting it back on all four wheels. The mirrored situation happens if the car leans right.
Wow, that little Cox engine ... that's a blast from the past. Must've been 1972, if memory serves correctly. Being in Sweden at the time, mine was attached to a (highly simplified) little balsa Draken plane. Good times indeed.
A pal and I mounted an .049 on a slab of wood and added three wheels and let it zoom around a school parking lot. It would go in expanding circles until it hit a curb or it crossed the road and hit a ditch. Pretty sturdy. No disintegration-on-impact like balsa airplanes.
I don't know what toys you have, but my toys today are RC planes with a 25km range that transmit HD video so you can fly them with a first person view.
Thanks, this gives me something to look into. I've been too busy the past few years to fly my long range planes and need to catch up on what's changed.
It depends on where you are and what license you have, but generally LOS is different from VLOS (one means there are no obstacles between you, the other means you can't see it).
Generally, there are limits to how far you can go, but you can get a license and file flight plans.
I had the P-51 Mustang one in the late 80s. At the time I wanted to be a pilot and was busily building balsa models, windup flying models, plastic Testors models, and Estes rockets.
The thing with the Cox airplanes was they were cheap enough for your parents to actually buy one. RC stuff used to be really expensive and clunky. My first RC plane was in the late 2000s and it was about 5 foot wingspan and had an even bigger, even messier glow-plug engine like the Cox flyers. I had to join a club to go fly it cause the radio equipment was still kind of sketchy. Total cost once all the accessories to fly it were included was probably closer to $1000 and even though it was "Ready to Fly" it still probably took 10 hours of work to get it actually flying well. (By that point the models were starting to be partially assembled in China)
If it cost near $1000 in the late 2000s with it being partially assembled in China you weren't getting much in the 70s or 80s at an affordable price with it assembled in the US, so anything good meant many hours of you assembling it. Hence the Cox type stuff that was a couple pieces of cheap plastic.
I crashed mine for sure, but never that badly. It was pretty good fun and I used it for a good period, though never without supervision. I never managed to learn any tricks, but I remember seeing an adult at the school fields one day who had one and was very good and did all kinds of tricks.
I have a DJI drone.. it's amazing.. but is it actually as fun as that old stuff that took 10x-100x more work to get it to work? No, I don't think so, for me it's so easy it's kind of boring, though a good portion of that is that it's a quadcopter. Fixed wing is so much more fun to fly.
> I don't think so, for me it's so easy it's kind of boring, though a good portion of that is that it's a quadcopter. Fixed wing is so much more fun to fly.
Makes some sense you find it boring, it's essentially flying itself. Conventional
remote-control helicopters have gyros for stabilisation but I don't think
they're anywhere near as easy to control as quadcopter drones.
If you are in the Portland/Vancouver area visit Delta park on most weekends and there will most likely be a group flying. If you have the chance to catch a competition at Delta park you will most likely see any number of former world champions.
I still remember those from my airplane model building years! When I joined the airplane modeling club at the local House of Youth here in the Czech Republic, we had a few of them still hanging around under the ceiling - but we never flew them by that point.
People were mostly building analog glow spark or detonation engine powered planes or electric and unpowered gliders.
Interestingly the thing basically all people built at tje start was a throwing balsa plane and then an uncontrolled glider, that you would drag up using a line, kinda how manned gliders are lofted with a winch.
Then every year we would hold a competition where members would compete with the planes they built - IIRC my glider was in the A3 category but I don't think I won any top spots back then. Also one way to assure victory was to build a bigger glider in one of the categories no one else competed. :-)
By doing it this way the club members learned how to use the tools and materials to then build more advanced designs - I managed to also build a RC plan eventually, powered by a 1,5 cm3 glowspark and controlled by a SkySport 4! I think 9 still have it somewhere.
Then high-school started and I had much less time and that was it with airplane building back then. :P
In the Bay Area you can find people flying at the model airplane field behind the Oakland Airport (https://goo.gl/maps/TBJTFuUoWhHapCwk7). It's quite a spectacle.
Oh my. I got a then already very old Russian compression ignition engine like this [0] as a child. It needed a mix of petroleum, aether and rhizinus oil and was extremely hard to start. I did not have any spring or electrical starter and it took forever. Will never forget the sound and smell once it ran though.
Oh. Thank you, I did only check the direct translation indeed. Learned something today. :)
That oil is for lubrication, the petroleum is the real, main fuel and the highly flammable aether is needed to be able to ignite at all at the comparably low temperatures you can produce with cranking. Too high compression and the first firing will see a too high counter force to continue, too little compression (that screw on top of the cylinder head) and it won't ignite...
We still had those at our aircraft model building club in the 90s as "that old thing" with the then new (at least for us) glow spark engines being all the rage. ;-)
We used to have the cox sky copter with the same engine. It had no control wires, you just let it go and it would ascend until it ran out of fuel and then it descended by auto rotation. It wasn’t that fun though, as it usually got stuck in a tree or on a roof on the way down. One day it just took off and disappeared, never to be seen again. We also had a dune buggy with that engine.
I vaguely recall it being annoying to start, but was with my dad so he definitely helped with getting it going. We had a bunch of soccer fields behind where we lived, so we flew it there to avoid any accidents.
It did eventually crash, but was fun while it lasted.
Yes, in the 1980s. It must've been Christmas gifts, and my brother got a P-51, and I got a Spitfire. They were made of plastic, and looked more like realistic scale models, rather than what in the photo looks like a hand-painted balsa wood kit.
(I don't recall we ever ran the engines. Probably told to wait until we went to a place with room to fly them, and then probably parts were lost before that could happen.)
Speaking of most dangerous toys of that era, I'm troubled to recall that we dumb kids threw around lawn darts, which already looked of vintage design by the time we got them, second-hand. There must still be holes in our garage. We're so lucky no one ever got hit, because now I realize those things could easily maim or kill.
We must've also had figurative guardian angels when (pre-helicopter-parents era) speeding around the streets on our bikes, walking through active train yards, disassembling and repairing high-voltage and motorized appliances and machinery, wandering off on trails and into the woods, etc.
Track meets are a little chaotic sometimes with all the events going on both the field and the track around the field. I guess someone actually was hit by a javelin at one point. From my searching it seems like these days its only just starting to come back to some highschool programs.
It's weird to think that these are considered so unsafe you can't have one anymore, seeing as by that time people were well into complaining about how the nanny state and/or lawsuit-concerned companies wouldn't let anyone have fun anymore.
(it was, to my memory, an annoying and silly toy, like everyone else is saying)
i don't get this - control-line planes were very popular in the 1960s and were not particularly dangerous. I built and flew a couple of diesel engined ones myself - not very well, it has to be said. the main danger was not getting your fingers out of the way of the prop when you flicked it to start it.
the advent of cheaper radio-control systems kind of saw them off. one of my flatmates in the 70s built a beautiful r/c slope-soaring glider.
I had several of these (or more properly went through several) and got proficient enough to do loops, fly it inverted in the other direction, and occasionally "land" as you were supposed to do when it ran out of gas.
It was a lot of fun, but because you were in the center of a SPHERE the axis of control was not as intuitive as one might like. In particular, going "up" changed the orbital "plane" (no pun intended) and as a result was going to intersect with the ground unless corrected. You could do a little bit of hackery by squatting down and standing up to change the spheres center but trying turning rapidly in a circle while in a squat, it doesn't work well!
One of the adjustments that was "picky" was setting the vertical stabilizer for consistent yaw. You wanted the plane to pull toward the outside of the circle, it would do that from centripetal force once it got up to speed but before then a bit of help, well helped. Too much though and if you tried to fly inverted it started flying toward you and that wasn't helpful at all.
The best thing about the engines were that 12 yr old me could completely disassemble them and rebuild them in about an hour. That was something you had to do, Cox would "refurb" an engine (which I had them do once when I found a wrecked plane that clearly had been out in the desert for > a month) but once I got good enough at it I could do the refurb and save the $15 + postage that Cox wanted.
I had a couple Cox planes at various times growing up. Starting them was a bear - either I flooded the engine or the battery I had for it was shot. Once I did get the engine running on one and immediately got my fingers bloodied up by the plastic prop.
When I got older I found out there's something called a "chicken stick" that you can use to flip the prop around to start the engine. Too bad Cox didn't include one, ha ha.
How about 1950s airplane non-toys? When we went through my dad's stuff, we found some wings that were about three feet across. On the top they said something like "This does not contain anything useful even to an enthusiastic amateur. The owner is a struggling scientist engaged in upper atmospheric and cosmic-ray research. If found, please return to <NAME> <ADDRESS>".
The skin on those wings was insanely thin. You could break it with a fairly gentle touch.
I had one of these as a kid! I could never get the "glow plug" engine to actually fire up, though, so I was never able to fly it. Sounds like I missed out on a spectacular crash.
Or a missing finger. Those things are pretty nasty to get going without a starter motor. Some of them come with a spring loaded starter, those are a little bit safe, but the ones that you start manually are really nasty.
edit: Hah, that's actually mentioned in the article.
Really, the mechanical integrity of the motor/plane mount and everything else comes into play when the thing starts up and if you're not treating it with all of the respect that it deserves you can get hurt very badly. I used to live right next door to a model airfield and more than one person left that field with serious injuries from spinning props. Starting them is the most obvious moment when things are dangerous but then the speed is still quite low, once they rev up you are much better off not to be in front of them or in the plane of rotation.
Electrics aren't much safer. These models are nothing short of amazing but the safety issues are very often overlooked and minimized.
depends on the capacity (and hence torque) of the engine, a sensible person would always wear a thick glove! besides, kids back then were pretty impervious to injury.
Right... well the number of times I've seen the ambulance ride out to that field tells a slightly different story. The problem is that every time it goes right your risk tolerance goes up and after a while people stop seeing the risk entirely. Same story in machine shops.
I think the real issue is that these are not toys, some of those motors pack an awful lot of punch, much more than the size of the motor would convey to a casual observer. Likewise for LiPo packs, those things are extremely impressive from an energy content perspective and yet, the number of idiotic things I've seen people do with them just baffles me.
After a long history of making, building and using all kinds of dangerous stuff I still have all my fingers. But I did manage to break my leg on an experimental bike so even the cautious can get caught out.
Oh, I just noted the helpful little table on that article I linked above:
Ultra Micro- Micro= Break the skin/ light bleeding, can cause serious eye damage
20"- 25" wingspan= Deep cut requiring surface stitches
25"- 35" wingspan= Deep cut through muscle, damage to tendons requiring multiple layers of stitches and possibly even surgery.
35"- 50" wingspan= Can cut to the bone, cut tendons, surgery required to fix damage.
50"- 70" Wingspan= Damage to bone, broken fingers, cut tendons in arms hands and legs.
70"- Large Scale= Lost fingers, serious deep tissue and tendon damage, cut arteries potential death
Giant scale= Dismemberment, can take off fingers even arms or legs, can likely kill especially if it hit you in the head.
The "glow plug" was kind of shaped like a spark plug, but instead of a gap for high voltage arcs, it had a small loop of platinum wire.
To start the engine, you had to pre-heat the plug. This entailed attaching a battery, clipping one terminal to the top of the glow plug and the other to the engine, to send a current through the platinum wire. You'd use a 'D' cell, or maybe one of those big old No.6 types. A mere 1.5V, but you needed enough current to heat that platinum wire.
This electrical apparatus had to be disconnected from the engine before you could fly the plane. Not sure if you could detach it before starting or not. That little wisp of wire would cool pretty darned fast with the current removed. I know with the larger RC planes the practice was to leave the glow plug heater attached until after the engine had started.
Anyway, once the fuel mixture hits that hot wire, there's this catalytic reaction where the fuel at the platinum surface burns extra hot. This imparts enough heat to the glow plug wire to keep it hot enough for the next stroke. Idk what magic keeps the fuel from detonating before the piston reaches top of stroke, but I can attest these engines are fussy little things. They didn't idle very well; throttle them down too much and they just conk out.
You can see other examples of this catalyzed combustion, and get a sense for what goes on inside the glow engine. These butane cigarette lighters that burn blue have a little bit of catalytic wire in them, you can often just see it glowing white hot just inside the flame opening. There also used to be these propane powered space heaters that had a gauze mesh of the stuff to boost the combustion efficiency.
Yes, it was a big dry cell - there's a wire in the cylinder that glows orangey-red when powered (it was easy to unscrew the cylinder head to inspect the 'glowplug'.
from the article it seems it's not a true "glow plug" heating element like one may use to start a diesel engine. my impression was the engine is so small the radiant heat of the engine is what causes the fuel to ignite in the chamber - seems tough to start cold
diesels don't have a glow plug. a glow plug has a radiant coil that ignites the fuel, and then the heat of the engine keeps it firing, which is different from diesel fuel.a diesel engine depends on heating the fuel via compression with the energy being provided by the human flicking it. there is no battery input to a model aero diesel engine. a car diesel engine uses a starter motor to provide the initial compression.
Just about every single automotive diesel engine sold since the 1950s is equipped with glow plugs, so the above post might be confusing.
Automotive diesel glow plugs do not ignite the fuel; they lower the required compression in cold weather by warming up the air going into the combustion chamber.
They're not the same things as glow plugs found in methanol-fueled model engines, which also do not ignite the fuel directly, but serve as a catalyst so the methanol can combust via compression instead of electric ignition.
When talking about glow plugs, it's important to specity the sort you're talking about and the context in which your discussion is taking place.
i admit i am not an expert on modern auto diesels (i remember my brother muttering about having problems with this on his Merc). but 1960's model diesel engines did not require a battery to start them.
Mercedes diesels were push-startable well into the 1980s. They still had glowplugs (even in the 60s) and if you did have a battery they would heat up the precombustion chamber to lighten the load on the starter motor.
A modern analogy is remotely-piloted aircraft / drones. These come in several variants. Related to the article, they can be dangerous; ie they reach high speeds, high altitudes, contain 1 or more rotating blades, contain high-energy batteries, and sometimes don't have great failure modes in the event of lost link, out of batteries etc.
I think a fundamental difference re the article's description is modern drones are capable of being flown safely. There are ways to build, maintain, and fly them safely, and ways for them to end in tragedy. It sounds like the 70s toys are dangerous as a default.
Some sub-categories for anyone not familiar:
- DJI quadcopters: The most popular type. Command-based controls; they're generally safe, easy to fly etc. Use electric motors and lithium batteries. Popular with photographers, as a toy etc
- FPV quadcopters and fixed-wing aircraft: Often have a degree of DIY and custom builds. Run one of several open-source firmware. Can go really fast, are very maneuverable, and can be flown for long distances. Can have various safety issues such as reckless flying when near people or animals, flying too far from the operator or with obstacles in the way without a good lost-link response etc. User assembly can lead to problems like weak solder joints coming loose. Various degrees of automation including autonomous flight, manned-AC-style autopilot modes, and angular-rate-based manual control.
- Model airplanes: Commonly flown by an older demographic at airfields, with direct line-of-sight between the pilot and aircraft. Control signals directly command control surfaces without a flight controller. May be ICE or battery-powered. Community-enforced safety standards. Less likely to go lost-link due to no BVLOS capability.
This post, and all the comments here, brought back lots of memories for me. I too have the faint scars from hand-propping these things ... or was it from the roman candle exploding in my hands in the midst of a roman candle war with other kids in the neighborhood? Estes rockets, chemical sets, control line planes, all part of my lived experiences as a kid in the 70s. It was certainly a unique time to be a kid - very little direct supervision during play time - few rules - basically be home when the automatic porch light came on.
You could do stupid things like take your parents car out for a spin after midnight at age of 13. Then having the only consequence of getting pulled over by the police being a stern lecture and having the cop follow you home with a warning to never do it again...
I am one of the lucky ones! I had the hand me down erector sets- WE made race cars with Rat traps as the motive force. I had several Gilbert Chemistry sets. I asked my favorite aunt to get me sulfer and Saltpeter - I made some rather good black powder- Solder the bulb from a "flash cube" to about 100 feet of found telephone wire, put powder and bulb in a rigid tube, stand behind large diameter tree and touch wires to D Cell. While I do not work in the field, I still love chemistry and will occasionally do silly chem experiments like Instant fire from antifreeze and a strong oxidizer. Make my own lime by calcining shells, and then disolve in water, filter and show how blowing through a straw generated CaCo3 again. Being child like means you can always be entertained easily.
I had the 80s versions of these, a cox P-51 and a red little toni cosmic wind. Super fun once you could get them started but also crazy messy. Playing with them lead me to build an RC Great Planes PT-40 (0.40), a super sportster, a gentle lady rc glider, and another glider that had an electric motor with retractable blades to launch it. Instead of standard gliders which used a whole roll of rubber tubing as large as a soccer field. Then I got into RC helicopters which are pretty difficult to learn how to fly but absolutely crazy what you could do with them 3 dimensionally once you did.
So much of my kid job money, allowance, holiday and birthday money was spent going through the Tower Hobbies catalog. Good times.
I remember these as a kid! I always wanted an RC version, but couldn’t afford one until I was an adult.
The minibee ? Microbee? I can’t remember what the engine was called was so small!
I still love the smell of castor oil to this day.
If you built one from a guillows kit, it really was more emotionally painful when it crashed than anything else.
The little engines were really pretty safe - even hand starting with a stick.
Once you got to an 0.25 or a 0.46 you might have a bad time.
My favorite plane though, wasn’t control line, it was actually a much much much later hanger 9 alpha. Technically a trainer. But I put a much larger engine on it. (Though the evolution .60 on it was amazing in an Escapade .40 …)
(Actually the escapade .40 might be a good second…)
I still have a control line somewhere… though I think it was cloth covered.
"Inadvisable experiments with Estes motors" was a staple of the 2000's for me.
Unfortunately around 2009 or so there was a change in regulations that made them practically unobtainium in my home country, the importer started getting demands from customs for an "explosives permit".
In the early 70's my local park had a flight circle for these. I could only envy the gas engine flyers, but had a good time flying my Guillows balsa wood gliders and rubber band planes.
I have seen one of those engines powering a drill bit: Someone needed a hole drilled into concrete under water; and building a single use tool was their solution. Worked pretty well, too.
this was before battery powered drills were a real thing, I should mention. And this was a crew that would spend a day inventing a solution instead of spending $20 to buy one.
Big concrete block, in a waist deep puddle. This block is the base of the drain pipe for a pond; the drain is opened all the way so there's a lot of water flow happening in the area, too. They're drilling an anchor hole and had a long enough drill bit to keep the engine out of the water. We had a rope on them to pull them out in case they slipped somehow, too. Probably wasn't a situation where we should've had a human.
I want to say it was using most of an air drill as a mechanism? I dont recall details if i ever knew them. These folks were mechanical hackers of the first water; this wasn't the most insane thing i saw there. by far.
I don't exactly agree with the article's comment that, "the fuel is ignited by the glowingly hot engine itself" - sort of implies the engine body proper is some hunk of hot glowing metal.
Wikipedia's description matches my memory that "the ignition is accomplished by a combination of heating from compression, heating from a glow plug and the catalytic effect of the platinum within the glow plug on the methanol within the fuel."
I'm sure most kids aren't big on personal protective equipment but seems with some gloves it wouldn't be too bad to start. This reminds me of a "friction welding" toy set from around the 70s/80s that was featured on HN a few months ago, which may seem potentially more dangerous without experience on either
I had one of these in the 90's! My father and I put it together, got it working and went to fly it. Unfortunately on its first voyage he crashed it pretty hard into the ground and it wasn't to fly again. I was pretty sad (10 years old or so), but now I know that such wasn't uncommon.
I got a Cox Red Baron in 1972, as I recall. Sad because I lived right next to a huge school yard but was never able to get it started. I had no one to ask how and why these things worked. It sat in the box on a shelf for the longest time.
I find this division on "hobby" and "toys" very strange.
I participated at local "airplane modelling club" at my 9-11 years and we had these control-line planes with ICEs (hand-built from scratch). Only "glowing plug" ICEs were very high-end and rare in my country and we used compression (effectively 2 stroke diesel!) engines which required very specific fuel: 1/3 of kerosene, 1/3 of castor oil and 1/3 diethyl ether. Ether were hard to get by, but my grandmother was surgeon nurse ;-) And, yes, 9-year old flight these planes under supervision of club's instructor.
R/C planes were known, but electronics for them were available only in very big clubs ("Pioneers Palace", one per city in best case, if you live in big city).
I have a very similar experience about a decade later in a follow-up organization to the SVAZARM/pioneer ones.
By that point the control line planes were just hanging from the ceiling and detonation engines were on the way out with glow spark replacing them mostly. People also had general acces to multi channel RC and we had one vintage "communist era" single channel on/off RC set as a curiosity. :-)
I've fall into hole between rich state (when such clubs were comparably-well-funded) and rich parents and full shops (when it become possible to buy materials, engines, etc., for money of participants themselves), so our small local club has only 2 working carbureted compression ignition engines (it is named so in English according to Wikipedia) and one glow-plug engine, all other were cannibalized for parts...
The thing I get a kick out of is that the picture is clearly from the 1990s: I forget what we called those pants, but I remember the giant high-tops were all the rage when I was in 4th and 5th grade.
