2.26.2011

what are you going to do with your life?

Titanum Electron Gun is key to space simulator. Engineer, James Stephens, checks new Caltech gadget.
How did my dad know what he wanted to do with his life? How did he know that he wanted to be a mechanical engineer and build rockets? That question is an oversimplification. He didn’t really build whole rockets but he worked on bits and pieces of rockets and on the robots and astronomy satellites that rode up into the sky on those big tin cans. Still, he always made it sound like he knew exactly what he wanted to do in life and he went right down the mechanical engineer path through school, to work at Rocketdyne, and on to The Jet Propulsion Laboratory of Caltech. I suppose that the glamour of things that are new, bold, and uncharted helped make it an easy decision to pursue rockets and space stuff.

I am in my forties now and I still don’t know what I want to do. I bought into in the whole do-what-you-love thing but it has never really gotten me anywhere that would look like success to most of the people walking around on this rock. I am happiest making things with my hands (the engineer homunculus in me throwing its weight around) but what things I get a kick out of making is always changing. So how does one get the $$ out of that? I’ve never really found the way to make my talents into cash. I suppose I should have gone to art school but I just didn’t want to jump the hoops. I suppose I should have followed the engineer path, but it seems to me that engineers don’t have the fun they did in the age before CAD/CAM and all the computer screens. Sitting in front of a glowing screen all day makes me cranky. It just doesn’t hold up to the tales of early rocket engineers tinkering with hydrazine and living on the edge.

This beats the heck out of an exploding rocket, no?
Digression Warning: skip this bit if you don’t get a thrill from tales of chemical stinks and medicinal serendipity. According to anecdote, use’ta be, in the early days of rocketry and super volatile liquid fuels there was no sophisticated way to check for leaks in the completed and fueled up rocket standing out on the launch rig. A tiny little leak would be a baaaaaad thing resulting in certain disaster. You want all the rumbling flame to shoot out of the nozzle on the tail of the rocket, you see. If anything is squirting out in the wrong place it tends to screw up the works and make everything into a big flame ball that goes nowhere fast. Fortunately the hydrazine in the liquid fuel smells like ammonia. (Don’t quote me on this. I’m running on anecdote and my cluttered and fogged memory here, not on any sort of expertise.) It’s toxic as all get out in larger doses but someone had to be the canary in the coalmine. One person with a good nose and the short straw would have to go out to the launch rig, climb a ladder, open a little door on the side of the rocket, and sniff. No ammonia stink? Thumbs up, it’s launch time! So tonight, let it be Löwenbraü. “Where’s the medicinal serendipity?” you ask. Guess what? Hydrazine is a chemical precursor to thorazine a.k.a. chlorpromazine, an antipsychotic drug sometimes used to reduce effects of a bad LSD trip. Better living through chemistry and the canary feels aaaall riiiight.

Dad was a thoroughly practical space engineer, a loud-mouthed critic of manned space flight, and the fly-in-the-ointment of every hair brained NASA pork barrel project. I don’t know for sure if his boosterism for robotic spacecraft and his practicality was something that grew in time or if he came right out of school swinging the fists of practical testing and fanatical belief in building spacecraft the way Ford cranked out Model Ts. It is telling, however, that one of his early big projects at The Jet Propulsion Laboratory was building a testament to practicality, the Molesink, also known as The Molecular Sink Space Simulation Laboratory. That’s a mouthful. He kept the black sign that labeled one of the steel doors opening into the big room filled with huge vacuum pumps, tanks of liquid nitrogen and liquid helium, and pipes running every which way patched here and there with ape shit* (that one I’ll have to explain later). Long after it went out of use and was scrapped, dad was proud of the big space-making machine that gave him his hernia. We still have the sign. It makes the shop in the garage seem more important.










Galileo's broken umbrella
The nuts and bolts of basic mechanics are tweaked by the very low pressure, intense cold, and ionizing radiation of space. The simplest assumptions made about mechanical parts or electronic devices down here on the ground are often poor designs for spacecraft. Lubricants for moving parts turn into horrible glue or worse they disperse, coating everything with a nasty muck. Materials cold-weld together in unpredictable ways, and plastic polymers just plain freak out. Armed with the Molesink and its threatening almost-like-space torture chamber dad would tear gaping holes in the blueprints of impractical and poorly designed spacecraft long before they could get into space and fail where no one was watching or taking notes. What was so practical about that? The big idea was to make a little bit of space here on earth to find out what was going wrong and to learn how to do things right on the cheap. It costs a whole lot less to wreck your electronics in the Molesink than to send them into space and then sit and wonder what went wrong. This may seem obvious but lots of obvious things get buried in the clumsy machine of NASA. Pork projects get arbitrarily farmed out to companies with no practical experience in a particular field and the same old mistakes are made anew. When the Galileo spacecraft’s main antenna failed to unfold my dad lamented the loss of the Molesink shaking his head. Stuffing a prototype antenna in the Molsink and opening a can of space whup ass would have prevented the whole embarrassing mess by proving the design sucked rocks. Lots of dopey mistakes plagued NASA in the 80s and 90s. The Hubble Space Telescope went up with out anyone trying out the optics. There was a terrible lack of attention paid to proponents of practicality like Dr. Fly-In-The-Ointment Stephens.

Dad worked on lots and lots of projects in his time at JPL, but he was slowly moved out of the nuts and bolts stuff. Eventually he was part of the Technology Affiliates program. It was intended to take new technology and inventions produced by NASA folks and make them available to private companies in need of innovation. Dad criticized the Technology Affiliates program for trying to find a problem for a given solution when he should have been finding solutions for problems. In his own time dad had a little business doing just that. He called himself the technology pimp, hooking up hard-up companies with willing, able, and well-endowed engineers, chemists, and biologists. I think dad had more satisfaction in his pimping work outside of JPL where he could fit solutions and people to a particular problem rather than doing it all backwards at JPL.

I need to dig in the dad box and find the documents so I can get the details right but I think there is evidence that he wasn’t totally happy with his position at JPL in the later part of his career. I think he really liked being the technopimp but the Technology Affiliates program didn’t bear much of fruit. There are a few letters regarding dad being turned down for a promotion/raise in the last few years of his time at JPL. Maybe he was just trying to get a higher salary locked in for a better pension, but I wonder if he was just burned out by the bureaucracy and silliness. I wish I had had the mind to ask. There are lots of things I never thought to ask… like, “How in heaven’s name did you know what you wanted to do?!” Was it all just a ruse? Maybe he was just faking the whole time and he never was that confident of where he was going.

not the right shade of grey
*So, what the hell is ape shit? Nope, didn’t forget. It’s a really tenacious thick grey clay-like stuff used to patch up insulation on cryogenic plumbing. At least that is what my fogged brain remembers. It comes in a big rounded log like an ape pooped it out. We had one of those logs in a drawer in the garage up to just a few years ago. Maybe that was what made dad so sure about what he wanted to do… engineering was just an excuse to say things like, “Hey Joe, toss me another log of ape shit. There’s ice on this bitch kitty.” Don’t know what a bitch kitty is? That too will have to wait.

2.17.2011

Oh Lego, what have they done to you?

chunky homestead
Lego. There was a long stretch of the seventies and a bit of the eighties when my birthday or Christmas wish list was headed up by that brand name, or more likely the incorrect term Legos or Leggos, both officially frowned upon. What a thing those plastic blocks have become. In my day Legoland was a far away enchanted place somewhere in Europe where every roof was topped with rows of squat cylindrical knobs and people had yellow heads. It would be decades before a graft of Denmark was stitched onto San Diego County and the minilands would grow in the Southern California haze.

I hope to avoid making this post a rant about how complicated the Lego sets have become, lousy with special parts and crazy directions, or how so many of the sets are based on one film franchise or another… but they have. The seed thought of this post was about creativity and open-ended construction toys. I wondered if Lego had become closed-ended. There are still clearly open-ended Lego sets available but they seem overshadowed by other sets with glossy photos promising one off models of a chunkified Millennium Falcon or Hogwarts Castle. Even Lego’s “systems” of sets that are designed as parts of imaginary worlds seem to want to be movie franchises. Each set primarily focuses on the construction of one fabulous backdrop or one weird machine. I wonder how many of these sets are used to build only the featured model and then sit on a shelf. I have witnessed kids rooms (and adults’ toy shelves) crowded with these finished models. I have heard tales of frustration when the awkward structure of a Millennium Falcon collapses and small grey blocks scatter under the couch requiring a return to the tedious construction directions. How often do the blocks get recycled into new creations these days? I wish I could make some sort of sociological survey of this. I would hope to find that the majority of Lego blocks in the world are in a perpetual cycle of building and tearing down for recycling… a circle of life kind of thing or one of those diagrams of schistosomiasis making its way from host to host.

My nephew has his collection of Lego blocks in a large storage bin filled mostly with a jumble of individual blocks. He always has one or two constructions that he wishes to save from being scattered into blocky bits, at least for the short term. These sit in the air space at the top of the jumble waiting for the next time the bin is opened. Sometimes these constructions are right out of the direction manuals for a particular model, but more often they are some alien battle cruiser of his design or a skyscraper waiting for the plastic Godzilla’s next attack. Is my nephew’s M.O. the exception or the rule? I hope his way is the rule. It makes me all frowny to think of the gobs of Lego potential going to waste on someone’s shelf. I see those models and struggle against the temptation to modify them… use Yoda as a figurehead on a swamp fan boat or turn Hogwarts into a Tudor cottage…

My second set circa 1975
See the Atari duck?
The conversion of things into Lego language still sort of pixilates them and squeezes details into the limits of small plastic blocks, but the chunkification was much more severe before the addition of wild new colors, slopey roof bits, and articulated figures. Once there were only a handful of block shapes in five colors excluding the wide green foundation platforms. Back then the sets didn’t come with much instruction beyond the pictures on the box and the only special pieces were doors, windows, and wheels with their black axle blocks they fit into one of two ways. Cleverly, these wheels had the standard Lego knobs on their hubs so they could carry a chunky propeller or windmill blade. Building a person or a duck with these early sets produced something akin to a Space Invaders alien or an Atari Adventure dragon. The blocky graphics at the dawn of computer games primed me to be more than happy with my chunkified Battlestar Galactica. It took all the white blocks I had, was devoid of tiny laser canons, and scale problems forced the Cylon Raiders to be represented by paper hole punch confetti, but it flew lots of successful missions none the less. The lack of directions in these early sets didn’t stop me from trying to mimic some of the things pictured on the box. I remember squinting for a long time at that funny looking boat while counting how many little knob-bumps there were from one end to the other. That was the only way to decipher its actual length in Lego world. My second and third Lego sets each had more specialized parts than the last and eventually I had some sets with gears, axles, and universal joints. These last ones indeed came with complex directions for a featured model, but there were always lots of extra blocks and tantalizing other options for building. Making just the one model would be a betrayal to the left over blocks. The bulldozer eventually became a forklift of my own ingenious design and the harvester tractor supplied parts for a dune buggy complete with rear differential and working suspension.

I had other construction toys when I was a kid but none of them had the longevity of the bumpy plastic blocks and the possibilities opened by collecting multiple sets. There was a hodgepodge of hand-me-down tinker toys. They tasted good but the chew marks made the stick-in-hole joints unreliable. There were some Lincoln Logs. These occasionally worked in concert with the Lego blocks for some rustic contrast, but the set was small enough to only make a simple cabin or a one-floor frontier cathouse. Cool stuff, each with merits as creative toys, but they didn’t fire my imagination enough to plead for more sets and an ever-expanding empire.

We never had a big set of the standard wood building blocks at our house, but pop kept me supplied with lots of splintery lumber scrap. I could spend hours bashing bent rusty nails into these struggling to build clumsy bird houses, dog houses, or bug houses. I adored my Lego pile but this didn’t soothe my envy of the smooth wood blocks that one of the neighbor kids had. Nicely made wood blocks still have a strong draw for me. My nephew has a set that is a pleasure to stack and restack. There is something special in the standard shapes with a few wedges and arches. The limitations set by the simple design of the blocks becomes an invitation to creativity, and the possibilities become infinite. It’s something akin to a low-budget black and white film creating dramatic effect using little more than simple lighting tricks.

The new age of Lego with maniacal model building instructions winding through hundreds of illustrated steps has wandered far away from the simple open ended magic of stacking wood blocks. The old sets certainly had a closer relationship to this magic, and they had the added delight of allowing a kid to pick up a creation and fly it around. A rocket made of stacked wood blocks has little option but to blow up on the launch pad. Build it out of Lego and it can go to the moon. The newer sets are exciting and flashy but they may have lost some of their connection to the simple learn-by-playing toys exemplified by Froebel’s Gifts of Kindergarten. These are a series of toys designed to offer children expanding opportunities to learn through physical manipulation of interesting objects. The series begins with a group of soft crocheted balls on strings and grows into sets of, what else, smooth wood blocks! I don’t want to get too far into the details but suffice to say The Gifts are all simple toys that encourage open-ended play manipulating shapes and colors. Back in 1958 when the standard Lego block was patented Froebel might have accepted the sets containing five colors and a few shapes as a logical continuation of The Gifts. The menagerie of special parts added since 1958 make for all sorts of new possibilities but they steal something away too. Still, the creativity that pours out of the Lego box can be wonderful.

I’m a dork for creativity. I get all excited some times just from seeing bursts of creativity in others, like when my nephew balled up tiny bits of a paper napkin for an action figure snow ball fight. My nephew and I will often have Lego sessions, typically ending in an arms race to destruction with layers of Calvin Ball style made-up-on-the-spot rules: “Oh yeah? Well my house has lasers on the roof, see?... and surveillance cameras, so you better keep your Dr. No doomsday juggernaut off the lawn… or else! Oh, by the way, see those little black blocks on the foredeck? That’s the poop your Predator alien left on my veranda last week. You better get that thing house broken or I’m calling animal control.”

If we are at my sister’s house these antics come out of my nephew’s Lego box, but I still have my own old collection of blocks. When my nephew is at our house the old chunky style blocks jumbled with their later cousins, the gears and axles, suffice for our neighborly squabbles. My nephew regularly questions why my blocks are so lacking in sophisticated parts and small articulated figures, but the mechanical and robotic possibilities of all the gears usually make up for the shortcomings of the regular red bricks. Besides, if he thinks too long about the lack of hinged pale green translucent alien space ship wing thingies then my extra chunky Battlestar Galactica will cruise by and drop a teraton nuke on his half completed Neptunian meat processing plant before he can even install the rotating knives. Hey, it’s all part of the circle of life, right?

2.09.2011

we like more explosions

In which mr. a-go-go lists more of the dangerous explosive things that could have killed him in his youth.

As promised in the last episode here are some of the really dangerous things that I took delight in witnessing close up when I should have run far far away. My dad did all sorts of dangerous things but he always took precautions in his antics and he did his best to encourage my healthy respect for volatile chemistry. Unfortunately there were lots of other folks in my sphere who did not have such a healthy respect for dangerous things and I generally couldn't help myself when I had the opportunity to watch others do the crazy things.

Lets start with the spray can flame thrower... but first, another public service announcement. I said it in the last episode and I'll say it again... don't do this stuff. If you chose to do any of the things I describe here you may loose your fingers, your eye sight, and your life. With the hindsight of adulthood I can't believe I'm still alive and have ten fingers. Just from having been in the neighborhood of some of these idiot tricks, by rights I should be missing a few important parts at the very least.

So, back to the flame thrower. You may already be aware that the jet from many sorts of aerosol spray cans can be ignited to make a spiffy little flame thrower. Hours of fun! When I was a kid I had two neighbor kids as "friends" that were both a year older than me... a sure recipe for bad stuff. The spray can flame thrower was a favorite of one of these trouble makers. The rippling blast from a can of Rustoleum scared the small black poo poo out of me and I knew instinctively of the possibility of the can exploding but I could not turn away and flee. The pretty flame was captivating, even as my "friend" used it to blast the pile of oily rags in the garage. Their house eventually burned to the ground years later. Stunningly, it was the result of a grease fire in the kitchen. In light of the ever present strong gasoline smell from the spilled fuel for my "friend's" minibike, how did the house survive so long? The mini bike, by the way, was a 3.5 horse power lawn mower engine sans muffler, bolted to a bike frame with an ergonomic seat sculpted from a scrap of two by six lumber. Get yer saddle sores here! All of these people are still alive and well. Miracle.

But wait there's more.... When the Fourth of July came 'round my "friends" would egg each other on and soon they would be lobing ground bloom flowers high into the air with a wrist rocket sling shot. One of them would hold the little orange/pink cylinder at the ready in the sling while the other did the honors with a cigarette lighter (undoubtedly swiped from a cigarette sucking parent). The one holding the big rubber bands taught would stand trembling under the tension while the fuse sputtered and the other chanted, "Wait for it, wait for it." It just wouldn't do to launch the spinning devil into the air too early and have it spin into its wild color show after landing in the yard next door. They would carry this idiot dance to the very edge and let the fuse burn down until it was about to vanish. Then, zing! The ground bloom flower would do about half of its show during its high arching flight. Who knows where it would come to a spent smoldering end. Fortunately, I was considered too small and therefor unworthy of stretching the slingshot. I never had to turn down that honor. Still, I had to stay and watch when I should have taken myself far away from the probable fire emergency itching to happen.

Piccolo petes, those screaming road flares that normally stand on a small round plastic base, become wildly unpredictable missiles in the hands of your friend's pyromaniac older brother. This trick I witnessed in San Diego, and the close proximity of the inflammable beach sand and the large body of water saved many people's homes from these incendiary devices. Relieved of its plastic base and laid on its side, a piccolo pete will dart uncontrollably in a wild zig-zag and occasionally leap into a high arc of twenty feet or so all the while blowing its angry whistle. The flight is longer than a bottle rocket on its side and the mayhem is just that much more exciting with all the screechy noise.

Remember the model rockets I brought up in the last episode? In the hands of the same pyromaniac older brother these became so much more than a fast ride into the sky and a graceful float earthward on a little plastic parachute. The solid fuel engines that fit into the tail of these models are designed to spit some hot gas out the top end when the engine is spent. The intention is to deploy the parachute, but the mischief began when that same older brother discovered that this hot gas would ignite gun powder quite well. This revelation gave birth to a very dangerous series of Kaos rockets (in honor of the Get Smart villains). One of the early Kaos rockets just wasn't well engineered. A fin was torn off by the stress of launch acceleration and too much explosive had been packed too high in the rocket. The top-heavy monster turned and made three flips on the beach while I stood and gawked. Again, I should have been far away, but the anticipation kept me glued to the terrifying scene. One unfortunate bystander approached the dying rocket once it was stuck nose down in the sand and those of us who knew what it had in store yelled maniacal warnings to stay back. The charge blew soon enough that the naive innocent was still a safe distance away. The sand flew and the notorious older brother fled the scene. There were other Kaos rockets, but most were spectacular successes compared to this dud. The charge would blow high over the bay, and a litter of model rocket smithereens would be fluttering in the air before the loud report of the payload reached our ears.

Pipe bombs... yes, I said pipe bombs. These were improvised from PVC fittings and filled with home brewed explosives. These bombs were created at a friend's house and this time it was a notorious younger brother doing the mischief. I witnessed a few of these under construction, but I wasn't there when they made their craters. I suppose I was old enough by then to walk away, having at last outgrown some of my fascination.

So many things could have killed or blinded me. Old black powder sure is troublesome to ignite. When you get it sparking don't lean in to blow on it. You'll be enveloped in a sudden suffocating cloud of smoke and when the blur clears from your eyes you will find that your friend has only little shriveled smelly black knots where his eyebrows used to be. Sure it's funny now, but in the moment you stumble and think, "Ah! I'm an idiot!" and then you go and do it all again. I still love big bangs but I'll remain a distant spectator, thank you very much.

2.04.2011

we like explosions

Flying cans, gas bags, and other things that go BOOM (or BOMB as it were).

Ah, the Fourth of July, that most wonderful time of year when the neighbors would cower near the phone waiting to report the next flash bomb to the local Sheriff. In southern California the Fourth comes in the middle of the dry season and living right on the brush line in the foothills of La Crescenta my dad was a stickler for fire safety, at least until the Fourth rolled around. We'd spend most weekend mornings from March to October clearing grass and brush in a 400 foot fire break between the house and the thicket of Laurel Sumac, Chemise, and Scrub Oak bramble that grew on the hills. This stuff grows to a tinder box of thatch with or without rain over the years. Honestly, the Southern California scrub brush is a miracle of fecundity in what should be a parched moonscape. Fire was a perpetual threat and any whiff of smoke on the breeze would prompt a panicked search of the local news and the fire radio scanner for any word of where the fire was burning and witch way the wind was blowing, but the fires and all our work to prevent them will have to wait for another post.

Today I'm talkin' about making fire and loud bangs with wild abandon (but just enough caution to avoid death, mayhem, or bodily injury). In spite of all the work to prevent fires and all the admonitions from my dad about fire safety, when the Fourth drew near the sparks would fly. I have to give the standard warning about not trying for yourself any of the things I describe below. Really and truly this stuff can get you killed or at least badly maimed. Even in the middle of all the crazy my dad held us to a few really important rules. We could only do this stuff with supervision and things had to be arranged just so. Fuses were lit only when the explosive thing was resting on the ground and we had a clear place to run away. Keeping a safe distance for ourselves, and yes, for anything flammable was a lesson that was hammered in over and again.

We would have the standard issue big variety box of illegal small arms; the requisite sparklers that dribble scorching embers on your sleeves, some screaming whistling road flares, and plenty of showers of colored sparks shooting out of brightly colored paper cones. Then there was the real contraband; the brick of firecrackers wrapped in red tissue, and the collection of small bombs in cardboard tubes with stiff green fuses sticking out of one side. Oooh, these little devils had some punch and each of the kids on the block would get a few chances to set one down, gingerly touch a burning punk to the fuse, then run like hell as the little green cord popped and hissed. Then, BANG! Wheehaw! the thrill never wore off. The brick of firecrackers had to be savored and only a few bunches would be fired off in the rapid fire they were designed for. In case you have never witnessed a Chinese New Year celebration the standard practice for the strings of firecrackers is to hook the unwrapped bunch from a small loop at one end of the tangled fuses and hang it all in the air at the end of a long pole. This lets the individual crackers drop as the fuses burn down and they pop in a staccato tumble in the air. Ah, but we had other plans for the bulk of that big red brick. Once more folks, don't try what comes next. There are lots of things I did with dad when I was a kid that make me wonder how I survived. I would feel awful if anyone tried what I'm about to describe and got hurt. This stuff will put your eye out if you slip just once. No, really!

My dad introduced all sorts of tricks to my weird little brain, but the soda can rocket is a favorite memory. It required one empty aluminum soda can and one of those funny shaped extra tall Coor's cans. Remember those? I'd have to collect the cans here and there as we didn't have soda around the house often and the special Coor's cans could be hard to come by. The anticipation of the soda can rocket was so great that some years I would hoard Coor's cans that I stumbled on walking home from the school bus. We had some delightful neighbors with empty cans in the ice plant filled front yard. The open end of both cans would be carefully cut away below the shoulder leaving razor sharp edges to make your fingers bleed. Now the soda can would slip over the narrower Coor's can making a swell little cannon chamber for the cracker. To complete the rocket a hole of just the right size had to be punched from inside the soda can through the curved bottom that would be just big enough for a firecracker fuse. A singe cracker could be unbraided carefully from its palls, the fuse poked up through the hole in the soda can, and the soda can rocket was slipped over the Coor's can. The whole mess was set upright with the cracker fuse on top, a lit punk was touched to the fuse, and then everybody ran. The cracker would drop into the chamber and (usually) go bang, shooting the soda can way up in the air. Weeehaw! can't get enough. Lets do it again... and again.... and.... all day long, until the alarm call went out and the Sheriff would come by. We'd hide for a few hours and be back at it before sundown. Sometimes the cracker was a dud, and here one of those safety rules would kick in. Any can rocket that didn't go bang had to be left sitting for fifteen minutes before it could be rescued and reset with another cracker. You never know when one of those dud crackers could go off, and it'll always do it right when you go to pick it up. The duds all had to be disposed of in a bucket of water where they could soak until the paper turned to pulp.

Our Fourth of July celebrations usually had some kind of finale, some big bang bigger than all the rest, and that brings me to the gas bags that produced the brightest flash, the biggest chest compressing wallop, and the loudest whump I hope I will ever experience. These were delivered by my dad's favorite pyrotechnics, the big guns that he would only roll out once every few years. I witnessed the gas bag only five times or so in my life but that was enough. The photo above documents the mischief of the gas bag. By the quality of the photo, how young my dad looks, and by identifying the other engineer crazy person in the picture I know it was taken in the early 60s before I was born. The background is July grape vines and squash growing in the heat of a Tustin summer, and with what do you suppose he's filling that polyethylene bag? Yes folks, it's good ol' acetylene. Really, don't do this at home. This is one of those things I remember fondly and with some jaw dropping hindsight. These guys seemed to know what they were doing and no fire or death or maiming ever resulted from their antics, but looking back I can barely believe that I'm still in one piece after being witness to some of these bangs. Oxy-acetylene welding seems to be a dying art quickly loosing out to the newer TIG welders and their ilk, but back in the 60s and 70s a tank full of acetylene dissolved in acetone was easy to come by in any well equipped shop. If you have ever been trained in the use of the stuff you know the gas by itself has all sorts of explosive potential requiring strict handling precautions. Ah, but that didn't stop the mischief.

The gas bag would happen after all the standard illegal Fourth of July whiz bang was spent. Then dad would conspire with a neighbor or another engineer nut who happened to be around. They would find an open space clear of flammable debris and prepare a plastic bag taped to the end of a long tube. Not a huge bag, just a medium size, not to get carried away. (The photo above showing dad filling the bag directly is atypical by the way. Perhaps with age and experience he learned to make some more distance between himself and the bag.) Then the conspirators would let the acetylene flow down the tube and loosely fill the bag at the far end. All the spectators were gathered at a safe distance, the lights in the house were all turned off and everyone waited partly covering their ears in anticipation. When a source of flame was touched to the end of the tube a queer buzz sound would fly down the length of it. In an instant... FLASH! WHOMP! The air in my chest would be squeezed and the instant of brighter-than-lightning brilliance would slowly fade to red on my retinas. The hose was quickly coiled (not a trace of the bag remained) several people would rush out to check for fire and then we'd all hide in the house with the lights off waiting for the inevitable visit by the County Sheriff squad cars. They would cruise the street and scan with their search lights but seeing no fire, burst windows, or mad bombers fleeing the scene they would have to move on and ignore the pleas of the fainthearted neighbors still cowering by their rotary telephones.

Stay tuned for the next episode when I'll fess up to all the other crazy explosive things I stuck around to witness when I should have known enough to run the other way. You know, all the really dangerous stuff the kids were doing out of range of the adults. Remember those Estes model rockets? Hmm... how we can give these things a bigger kick?