BS: Rocket Science???

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 22 Jan 08 - 09:58 PM

We used aluminum tubing for rocket bodies and made the nose cone out of sheet aluminum. Fins were slid into notches as the tail and the melted propellant (technically known as "caramel candy") was carefully poured around a wooden vane centered in the rocket body. To finish we pressed another cone into the nearly-full end of the rocket. Firing was done by a 6-volt lantern battery.

The stories about burning the "waste" in Antarctica reminds me of the one my late friend Bob told me about Vietnam: the half barrels were pulled out the back of the latrines, doused in diesel fuel, and set alight. This was not a job for either the faint-hearted! One day someone opened the door below where the First Sergeant of calmly contemplating the news of the day, tossed on some diesel and threw a match -- without removing the half-barrel, of course. The flames of the burning latrine gave new meaning to the term "toasted buns."

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 22 Jan 08 - 09:39 PM

Most of the stories in the thread have centred on bangs as such rather than on their use in rocketry but there are a couple of episodes from my 15yr old adolescence where rocketry was at the centre of the event.

In Oz, there is a fine institution known as the Hills Hoist; every backyard seems to have had one. It is a clothes line for drying laundry, set out as nested squares on a pipework frame that can be raised and lowered and freely rotates; they usually have a radius of about 3.5m.

Some mates and I thought the one belonging to one of them would make an excellent test bed for a trial rocket powered by the usual gunpowder mix; in a built up suburban area it would be captive and still function without endangering neighbours. Made from a length of 1" steel water pipe and fittings, effectively, it was an open-ended pipe bomb strapped to the outside wire of the hoist. Apart from the spray of soot left on the painted side of the house where we lit the fuse it was a raging success but we didn't dare repeat it.

This led to another pair of events. I'd been reading CS Forester's series on Hornblower and there was a lot of description of naval actions involving the use of cannons. Cannon balls and grapeshot I could understand and accept but I was sceptical about the repeated descriptions of the effects of chain shot; chain shot was specified as a pair of cannon balls connected by a length of chain and used to disable rigging. To my mind, two balls from the one barrel were unlikely to separate far enough and the technology of using two cannons to simultaneously each fire a ball, connected by chain, from two barrels was nonsense. So I thought I'd experiment with the bit of rocket we'd used on the Hills Hoist.

I got a couple of 1/2" ball bearings and taped them to each end of an 8" length of keychain. I cut a transverse slot in the butt end of the assembly to take a fuse but, for reasons I can't remember I couldn't get the fuse to ignite the contents on any of the small test runs. So I got a 3v torch bulb and soldered a pair of leads to the business bits, broke the glass away from around the filament and inserted it, intact, into the slot with the leads (taped to stop any dislodging) going to a pair of dry cells. Perfect. I loaded it up with powder, wad and chain shot and another wad to keep it all together and took it down to the North Fairfield quarry, a place with lots of explosive bangs so the neighbours wouldn't notice; I forgot until after the event that Saturday afternoons were quiet times at the quarry.

I set it up so that there would be no recoil and I was at no risk and aimed it through some long grass at a large piece of old galvanised roofing sheet about 20' away, shorted the circuit and produced an almighty bang! It wasn't until my (younger) brother asked "Can you hear anything?" that I realised I could still hear; he was in the same state.

From the muzzle of this cannon there was a channel through the grass stems that gradually widened (I can't recall whether its shape was conical or 'exponential') until it reached the sheet, which had a pair of holes, 8" apart and joined by a slot with the same width as the keychain.

Blow me down! The chain shot notions could have worked and weren't just naval fairy stories. But I notice that Patrick O Brian's series on Jack Aubrey and Stephen Maturin don't mention chain shot at all. Ball, carronades, grape, canister and even bar; they all get a mention but there's no reference to chain shot.

Anyway, back to being 15 again!

For free-flying rockets we reckoned that water pipe was too heavy and we wanted a better fuel than gunpowder. We figured that the steel pipe used for bicycle frames would be the best option; relatively thin and thus light, no seams, easily available at the tip ("dump" for our US friends) in suitable length from old frames. A bit of brazing to block the tip with a cone and attach fins with the same twist as arrow fletches and we were away. I won't specify what we mixed with the sugar to make a very acceptable oxidising agent but I'm sure you'll guess. Some research had convinced us that a star shape (in transverse section) was the best profile for a combustion chamber to get maxmum propulsion from solid fuels, so we made one out of bits of modelling wood and tamped the fuel down the tube around it. But we used an ordinary Tom Thumb (opened at one end) with its powder and fuse to start it off.

Northcote High had a huge area of open parkland playing fields adjacent to its grounds and some were out of sight from both the school buildings and the main road, so we repaired there after school and set it up in the gathering dusk for a vertical flight. It went off brilliantly.

I have no idea of the altitude it reached but when it came down it came down about 1/2 a mile west of the launch site, across Merri Creek and in East Brunswick.

Into the main high voltage electricity substation for the northern suburbs.

Where a length of steel pipe more than 2' long was a perfect conductor.

Brilliant flash! And then the lights went out! And we skedaddled home into the gloom!

The news (radio and print) mentioned the incident but couldn't ascribe any cause as, apparently, no evidence was found.

And we're much older now.

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 20 Jan 08 - 08:34 PM

The other Mawson story came somewhat later, after Australia got serious about ensuring Antarctica was sustainably "clean".

They installed special gas-fired burners in Law Hut to replace the old 44-drum types described above. These were much more comfortable, as you didn't have to separate your functions; when you dropped the cover of the dunny seat, a burner would ignite and consume everything. I wasn't there to see these but I gather the nightwatch was easier too.

The gas used was Liquified Petroleum Gas (LPG in Oz and mostly propane) that was kept in large steel bottles ~4' high. In most situations such bottles are silver grey in colour and kept outside a building but Antarctica is cold enough to freeze the balls off a brass monkey (See the Mudcat thread on this) and at Mawson the bottles were painted black and were kept inside the hut; this allowed the liquid to evaporate successfully inside the bottle and send gas down the pipes to the various crappers.

ANARE has long believed that most of a plumber's tasks can be satisfactorily performed by a carpenter; our year (69) was the year they replaced the oil fired heating in the various buildings the station with a waste heat circulation system from the powerhouse and so we had a great plumber but that was unusual.

One day, someone reported to the chippie that one of the bottles in the manifold in Law Hut had a slight leak at the valve so he went off to check it. Not being a gasfitter, he got the spanner onto the bit below the valve on the relevant bottle and started to unscrew it. When there was only about half a thread holding the valve assembly into the top of the gas bottle, the pressure blew the whole assembly through the roof, releasing heavier-than-air gas into the building.

Bad enough, you might say, but he had been doing all this while talking with someone who was occupying a seat-of-ease and who'd just finished their business and put the lid down. They scarpered quick smart and got out just in time to witness the almighty blast from outside the hut.

I'm told they had a bit of a cold time of it for the rest of the year. And there's no evidence of a song about it. Pity!

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: Charley Noble
Date: 20 Jan 08 - 11:36 AM

Rowan-

Another fine song lost due to the negligence of ethnomusicologists.

Very sad!

Charley Noble

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 19 Jan 08 - 09:07 PM

When I was at Mawson we used det cord to take the tops off 44s; these are the drums (containing 44 gallons Imperial or 55 gallons US or 200 litres metric) that contained fuel on the way down but had various uses at the station. You just wrapped a length of cord around the drum just under the top rim and the top would come off as clean as a whistle.

But Mawson reminds me of other yarns with explosive effects.

Antarctica is seriously cold and seriously dry (although RH might be 60%, Absolute Humidity is 3/5 of 5/8 of precious little) which means nothing rots. So what did we do about sewage?

When I was there in '69, we burned the less wet bits, requiring us to be careful about separating our various functions; woe betide anyone who pissed in the crapper! The crapper at Mawson (officially "Law Hut", named after the director of ANARE, Philip Law) had a pissoir just inside the entrance (effectively the cold porch) and a row of 44s set into concrete such that their tops were at comfortable seating height. Each 44 had a flue hole let into its side about half way up the back and three of them had a timber dunny seat set into a removable lid; the fourth had a lid much like the inlet of a woodburning furnace, with a slide to control the intake of air. So that you didn't get the blizzards affecting tender bits of anatomy down the flue, each drum had a 'tompion' flue blocker that was inserted from the inside of the drum when it was in use.

Everyone took turns at being on nightwatch and one of the duties was to "burn off the crapper". This meant that you scraped out the ash from the one that had been burned off the night before (with the air-intake lid), using a long handled shovel affair and dumping the ash (along with the contents of the pissoir) out on the sea ice in the harbour, downwind from the station. Mawson had been in use since 1954 and had used briquettes as a fuel for a lot of that time, so we still had a fair dump of excess briquettes; fuel oil was the main heating fuel in '69.

So, put the flue tompion back into the hole, chuck half a dozen briquettes into the bottom of the cleaned-out 44, followed by enough kindling from old packing crates to create a pile about 2/3 up the drum's interior and then check the other three drums to see which has had the most use, transfer its seat-lid off to the newly setup drum and then prepare the exposed drum for burning by removing its flue blocker, chucking in another half a dozen briquettes and a cupful of oil and a match to set it burning, after which the air-intake lid was put on top, the air intake adjusted and away it would go.

But you had to remember to take its flue blocker out before you lit it, didn't you.

A couple of years after I was there, someone forgot! But they remembered when it didn't seem to be burning properly and just produced a lot of smoke. So they took the lid off, didn't they! And, as anyone with experience of fuels that are burning in a space starved of oxygen can tell you, if you suddenly introduce a whole lot of oxygen the mixture will suddenly give an explosive conflagration. And it did.

I believe John Illingworth wrote a song, using Villikans and his Dinah as the tune, celebrating the event but I've never been able to track down the words.

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 19 Jan 08 - 08:26 PM

Another use we made of Melbourne's town gas was to get a tin can with a tin 'press-fit' lid, drill a 1/4" hole in the lid and fill the tin with town gas, purging all the air. You could carry the charged tin outside (keeping your thumb over the hole in the lid), set it down with the lid uppermost and put a match to the hole.

A nice unoxygenated flame, about 1" high, would appear above the hole and gradually get smaller as the quantity of gas diminished, until the flame just disappeared into the hole. This occurred at the correct fuel-air ratio for the mix to ignite with an almighty bang, sending the lid high in the air.

The best part was that no part of the apparatus was damaged by all this so you could reuse it again and again. Of course, we had to try it (from a safe distance) with one of those four gallon (Imperial, 5 gallon US and 20 litre metric) cans with press-fit lids that various dehydrated vegies came in when in bulk.

Very satisfying.

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: The Fooles Troupe
Date: 19 Jan 08 - 06:50 AM

Rapaire - your uncleis probably the source of The Myth Busters item on their TV show...


"The mould was distorted beyond repair, and there was a casting-shaped hole in one wall of the foundry. "

Hmmm, sounds like he clearly fulfilled his contract -'get that fooking thing out of there' - he just should have been given a more explicit 'task description'!   :-)

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 18 Jan 08 - 09:17 AM

It would have worked. I've cut steel plate with det cord. LOOOOONG after my youthful hijinks, of course. I shudder to think what we would have done if we could have gotten our hands on det cord.

The story about the ingot reminded me of a story my uncle-in-law tells. He was working at a ready-mix cement company in DC at the time, and of course the mixer units on the cement truck HAD to keep turning so the cement wouldn't harden.

Seems like one of the drivers decided to pay a little visit to his girlfriend, drink a few beers, on company time. He parked the truck outside he door and spent eight hours inside. Naturally, the cement in truck hardened.

He got back to the yard after the Supervisors, etc. had gone home and found a note on his timecard -- something to the effect of "See Me Tomorrow!" He thought that if he could get the hardened cement out of the truck it might go easier on him, so he went home or somewhere and returned with ten sticks of dynamite.

The steel drum on a cement truck WILL contain the explosion of so much dynamite, but the force of the blast didn't even loosen the concrete. It did, however, bring many representatives of the police and fire departmetns, the BATF, and others.

The driver involved didn't have to wait until the next morning to see his boss, or his boss's boss, or his boss's boss's boss, or to meet the press, or....

Subject: RE: BS: Rocket Science???
From: JohnInKansas
Date: 18 Jan 08 - 01:05 AM

At "little B aircraft" ca 1970, our "explosives expert" was a rather colorful character that everyone called just "Boom-Boom." I'm not sure that I ever knew what his "real" first name was.

His tale of his glider flight into Bastogne with 2,000 pounds of high-explosives for payload was very graphic, and still scares me just to think about it. (I believe he said that only a two, of the 8 or 9 behind him landed "safely," so his flight was after the Germans had "zeroed in" on the approach paths. "Safely" was sort of a euphemism for "there were pieces left" after the "landing.")

He had a remarkable collection of tales to tell, but he was a professional and I can't give first-hand accounts, so they're not really appropriate here.

A complaint about a "balcony office" that had only one exit led to his proposed solution:

"I'll just stick some shaped-charge det cord in a door-sized outline on the wall. If there's an emergency, you just hit the switch and there'll be a door there."

(The plan was never implemented, although he probably could have made it work.)

John

Subject: RE: BS: Rocket Science???
From: HuwG
Date: 18 Jan 08 - 12:07 AM

Reading JohnInKansas's tale above reminds me of a story told by a late business partner of my father's, who was working as a chemist or analyst at Yorkshire Imperial Metals in Leeds, UK.

One day, the foundrymen at YIM contrived to make a mess of a casting operation, and found themselves with a gigantic ingot jammed into a mould. They could have course cut it out with oxy-acetylene torches but the foundry floor workers reckoned that it would be as quick to sit down and wait till it rusted through.

YIM hired an acknowledged "expert" in the field of explosives and demolitions - Blaster Bates. Bates proved that bravado and after-dinner repartee are not necessarily a recommendation. Examining the cast and calculating it was about "three tree roots' worth", Blaster packed several sticks of gelignite around the casting and fired. With the rest of YIM still working!

The results were several minor and one major injuries, the latter to John Jones from who I heard the tale, who was handling glassware at the time. The mould was distorted beyond repair, and there was a casting-shaped hole in one wall of the foundry. Lugubrious Yorkshire foundrymen retrieved the smashed casting on a fork-lift truck, saying expressionlessly to the foreman, "Can we 'ave a chit to put this in t'arisings bin?" (Losses during the casting process could be a disciplinary matter.)

John and my father were in business together for some years until John died in a car crash.

Subject: RE: BS: Rocket Science???
From: The Fooles Troupe
Date: 17 Jan 08 - 11:31 PM

"Where can I get one of those tee shirts?"

What? the ones with all the char marks and burn holes in? They're 'home made' mate! :-)

Subject: RE: BS: Rocket Science???
From: MaineDog
Date: 17 Jan 08 - 01:54 PM

As a retired rocket scientist I am enjoying this thread majorly! I hope I get to finish it befor Homeland security takes it down.
Where can I get one of those tee shirts?
MD

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 17 Jan 08 - 09:24 AM

And forget the "Dangerous Book For Boys." Get both the "Dangerous Book For Girls" and "The American Boys Handy Book". The latter two are waaaaaaaaaaaaaaaaaaay superior to the first.

Subject: RE: BS: Rocket Science???
From: Charley Noble
Date: 17 Jan 08 - 08:33 AM

Clearly, my classmates and I were relative innocents compared to some of what has been posted in this thread.

Cheerily,
Charley Noble

Subject: RE: BS: Rocket Science???
From: JohnInKansas
Date: 17 Jan 08 - 02:46 AM

On the same theme as Rowan's floating balloons, but without the flames and explosions, at a lab where I worked many years ago there was a plentiful supply of various "lab gases" including a tap on the wall where one could draw small amounts of helium, and a tank nearby from which liquid nitrogen was handy.

A small balloon - on the order of the rubber "finger cots" provided in the lab for handling "super clean stuff" - or another kind conveniently and easily available - could be filled with sufficient helium to achieve bouyancy and then tied off. If said "balloon" was then rolled around on the surface of a bit of liquid nitrogen in a petrie dish, it would collapse into something that resembled a "thing that might be discarded on a secluded road at night" (even if it was one of the "conventional lab" balloons).

If carried carefully, to minimize the heat transfer, this object could be easily transported for some distance to a place where there were "unsuspecting subjects who might need their day enlivened."

Deposited in a place where it would be first noticed in someone's peripheral vision (most sensitive to small movements), as the object absorbed heat and began to uncurl, the usual reaction was "puzzlement," and full awareness that something "really was there" usually came at about the time when the "object" inflated to it's full magnificance and rose gently to the ceiling. (The last stages of growth were usually quite rapid.)

It remained a fairly common, if sporadic, "social activity" until the arrival of a "rather stern" Management Directive ...

John

Subject: RE: BS: Rocket Science???
From: The Fooles Troupe
Date: 16 Jan 08 - 10:51 PM

"Use someone else's yard"

Preferably, get some other sucker teenager to do it while you watch!

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 16 Jan 08 - 10:42 PM

You must obtain and read the book "Backyard Ballistics." But don't try the stuff at home! Use someone else's yard.

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 16 Jan 08 - 10:33 PM

In 1956/7, before natural gas was piped to Melbourne from Bass Strait, reticulated "town gas" was the mixture of hydrogen and carbon monoxide produced from the reduction of coal. As delivered it was less dense than air and was used for various tricks.

One was to use a hose to blow bubbles from a soap solution; the bubble would rise in the air, often past an ignition source; very satisfying. Another use was to fill party balloons, on which unflattering/witty/adolescent remarks could be painted (this was before textas) before releasing them; they'd rise to the ceiling of any room or passage and stay there, well out of reach, until the hydrogen diffused through the skin of the balloon (more rapidly than the CO) and when the mixture reached the same density as the air the balloon would gradually descend and be removed by the cleaners.

Harmless fun, until one of our number acquired a meteorological balloon. At 3 metres diameter this promised fantastic results! The lab was in the upper floor of the school and, unnoticed during lunch hour, we got enough hose to put the balloon out of a window and fill it before tying off and releasing. The wind was a steady southwesterly and the eddies kept the balloon close to the ground but above the powerlines for the trams down St George's Rd. It was still close to the ground when it entered the area occupied by the Little Sisters of the Poor Convent, across the road and appeared to chase the horse in their paddock. Greatly amused, we watched the balloon disappear northeast over Rucker's Hill in time for us to return to classes; we thought that would be the end of it.

On the radio news that evening, I heard that housewife in Bulleen had reported seeing "a fireball, come in her kitchen window at 2.30 in the afternoon, sit over her stove, and then explode. The Met Bureau was interviewed and the wally waffled on about St Elmo's fire and other hypotheses. The next day, at school, we calculated that, from the observed weather, wind speed and direction, the distance from Northcote High to Bulleen, the time of the housewife's report and the likely diffusion rate of hydrogen from the balloon, her fireball was likely to have been our balloon.

So we rang the Met Bureau and put our alternative hypothesis forward. Were they interested?

Naaaah!

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: JohnInKansas
Date: 16 Jan 08 - 02:24 AM

A couple of old-time pilots I dealt with some years ago called the "assisted take off kit" for the F84 the "BOR kit."

BOR translated as "Bag of Rocks."

The explanation was that the F84 was so underpowered that it always needed all the runway you had (and sometimes a little more) in order to get off the ground. If you dumped a bag of rocks in front of it, it would think it was at the end of the runway so it might occasinally go ahead and get it up a little before you hit the trees.

John

Subject: RE: BS: Rocket Science???
From: Art Thieme
Date: 15 Jan 08 - 09:41 PM

In my uncle's case, we always referred to what happened to him as FATO!

Fart assisted takeoff!!

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 15 Jan 08 - 11:28 AM

If you throw cherry bombs down an outhouse with self-closing seat lids it can make for very interesting results for the next person to use the facilities.

Subject: RE: BS: Rocket Science???
From: Art Thieme
Date: 15 Jan 08 - 10:41 AM

Whoops, I just saw GUEST Astro's prior suggestion above for what is the content of my last post. Sorry!

Art

Subject: RE: BS: Rocket Science???
From: Art Thieme
Date: 15 Jan 08 - 10:37 AM

Smeared around the toilet seat when a really hot chick sits down on it can make for some unique pyrotechnics too!!!!

Art

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 15 Jan 08 - 09:03 AM

And the education never stops! Just a year or so ago I learned how to convert shotgun shells into hand grenades (and they'd work, too).

I find that I haven't even touched upon what I've done with incendiaries, and perhaps I shouldn't. But jellied gasoline smeared around the inside of an ashtray can surprise the hell out of the person who stubs out a cig.

Subject: RE: BS: Rocket Science???
From: Charley Noble
Date: 15 Jan 08 - 08:52 AM

Rowan-

I'm pleased that you and your family appreciate this thread. I thought you might!

And, Graham, what a lovely image you sketch of the tent flash fire!

It's probably time for the mandatory Mudcat disclaimer:

NONE OF WHAT HAS BEEN POSTED ABOVE SHOULD BE TRIED AT HOME, OR AWAY FROM HOME, WITH OR WITHOUT ADULT SUPERVISION!!!

Cheerily,
Charley Noble

Subject: RE: BS: Rocket Science???
From: Grab
Date: 15 Jan 08 - 08:07 AM

Not a pyro myself, but I was in the climbing club at school, and a couple of them were predictably short of the gene that tells the rest of us "uh, are you sure that's a good idea...?" An unsupervised trip to the school cottage in Yorkshire, in company with a large amount of (underage) alcohol, various preprepared sparkly-and-bangy things, and climbing and caving gear, was particularly memorable. So much so that I'm amazed nothing went too badly wrong. The wall above the fireplace finished off black with various stuff thrown/sprayed on the fire.

The only actual injury was to me though, and it was the lowest-tech thing you can imagine. One of the guys heated up a coin on the fire to orange heat, then put it on a bit of rolled-up newspaper and showed it to another guy. This bloke thought he was being threatened with it, so he kicked the newspaper, and the coin flew with absolute precision straight down the neck-hole of my shirt! With unusual presence of mind, I didn't bother trying to get it out but simply leaned right forward to get it away from my skin. In the 2-3 seconds while I was figuring out what to do next, the coin solved the problem by burning its way out Alien-wise through my T-shirt and sweatshirt, then dropping onto the carpet and burning through that to the stone floor. I had a neat round burn scar on my chest for a few years after that.

This was the same trip where two of the guys (the pyros, unsuprisingly) went abseiling from the Ribblehead Viaduct at night, and when asked where they'd tied the ropes off, they said "around the rails". Their main concern was getting a good anchor, and the possible flaw in their plan simply hadn't occurred to them - thank goodness British Rail didn't run night trains on that line.

For fire-related action, a particularly dim lad at school deserves a special mention. This was in the mid-80s when nylon tents were just starting to take off but weren't yet flameproofed. In defiance of rules he decided to use his Trangia inside his tent, and then he had a moment of curiosity and wondered what a lit Trangia burner looked like from below. For those who don't know, a Trangia is a meths stove which is designed to draw its air through a perforated panel in the base, so lift it up and suddenly you've got a whole lot more air reaching the burner. Witnesses said that it was very impressive to watch. The tent burned so fast that he was completely unscathed - the fire just flashed straight round him and burned the whole tent in a couple of seconds, leaving him sitting stunned in the open air as bits of tent ash dropped round him.

Graham.

Subject: RE: BS: Rocket Science???
From: GUEST,astro
Date: 15 Jan 08 - 12:05 AM

The memories of explosives...the contact explosives expert that I was...sold many a lot to other "adventuresome" individuals of the time in High School...Ahhh...I remember the adventures:

   . contact explosives under the toilet seats at HS
   . contact explosives on the chalk boards providing a musical note
      to high school chemistry
   . contact explosives under the swivel desk seats to add a nice
      wake up moment for students sitting down
   . in the key hole to the door of the physics class in hs...
      remember when they carted away the poor physics teacher due to
      shock...not my doing, but my product used by others...which
      spelled the end to my time as the engineer...

This then reminds me of the underground planetarium shows given...!


Astro

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 14 Jan 08 - 11:19 PM

And I suspect this also prompted Charley.

When I was 15 I was the school expert on explosives; I (and all my assistants) still have both our eyes and all our fingers so I must have been doing something right. I was also in the local archery club and you remind me of various exploits. I tipped some of my arrows with dead .22 cartidges when dealing with feral cats and rabbits and I experimented with Mg ribbon to make arrow-borne flares. My most successful arrowhead required a used carbon dioxide bomb of the sort used in soda fountains, some cartridge powder from a shotgun shell and a primer from the same shell. In the interests of not drawing the attention of ASIO and the CIA to Mudcat I'll give no further details but that it made a very satisfactory hole in a hardwood (redgum; 72lbs/cubic foot) stump at 100 yards.

But, again, I'm older now.

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 14 Jan 08 - 11:16 PM

I suspect this is the first of my postings that prompted Charley to resurrect this thread.

When about 15 I read in a newspaper article that the temperature in the tip of a burning cigarette was ~750 degrees F; I was sceptical about this but figured I could test the veracity with a bit of cunning. I knew that the ignition temperature of magnesium was less (~650 degrees F?) and I knew I could "borrow" a short length of Mg ribbon from the chemistry lab at school. My father smoked filter tipped cigarettes and I pinched one of his opened packets, carefully removed the tobacco, placed a short strip of magnesium ribbon in the middle and then carefully packed tobacco back in so that the finished product could not be distinguished from the other cigarettes in the pack, put it in with them and left the pack wher he'd find it. I figured I'd get to hear about any result.

A few days later he was driving us to the drive in in the gathering dusk and lit up a smoke. After a minute or so there was a brilliant light in the front of the car, a loud expletive and the flare was thrown out the window onto the road.
"What the hell was that?" he cried, as I watched the flare while we kept driving down the road.
"Dunno, Dad!" I replied. I don't think I ever told him I was responsible, but I was satisfied the newspaper article was probably correct about temperatures in cigarettes.

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: Rowan
Date: 14 Jan 08 - 10:08 PM

Many thanks, Charley, for pointing me to this thread; it's a ripper! I had no time to read it online so I printed it out and took it away with me to read at leisure. Daughter #1 (16 last May) was worried about the paroxysms of tears and laughter brought on by Fergie and Big Mick's descriptions of their escapades; she'd never seen me so convulsed. She had, however, been looking over my shoulder as I typed up my posting about the magnesium ribbon that you saw on the drive ins thread so she understood perfectly once she'd read their postings.

When I asked her if she'd known any of her peers at school to do similar things she said they were all too uninterested in such things; what is the next generation coming to? However, she mentioned a bright spot that had happened at this year's Nariel, a fortnight ago. For those of you outside Oz, Nariel is the oldest continuously running folk festival in Oz and arguably the one that kicked all the others off; it started in '62-3 as a weekend workshop to teach fokies from Melbourne (5 hrs' drive away) all the dances and tunes that had lingered out of range of radio and TV in the hills near the upper Murray of NE Victoria; lovely creek with trout, no electricity, basic bogs, $20 camping fee, corroboree ground, great music.

The teenagers are supervised only from a respectful distance and daughter #1 mentioned a group of them had brought 250 sparklers, scraped all the combustible stuff off their wires (I had wondered why there was a tangle of unburnt sparkler wires just outside the door of her tent) and into a large tin. They floated this item in the middle of the creek , lit another sparkler and jammed it into the mix (upright, to act as a fuse) and watched. It lit up the whole campsite, brilliantly, like the flare it was. It was quite some time after the entry of the New Year and I was asleep and missed it. The ringleader was a lad of 15, who promises to have all the exploratory nouse we have celebrated above.

Cheers, Rowan

Subject: RE: BS: Rocket Science???
From: The Fooles Troupe
Date: 14 Jan 08 - 09:54 PM

It CAN BE - on The Space Station... :-P

Subject: RE: BS: Rocket Science???
From: Mr Red
Date: 14 Jan 08 - 03:49 PM

Gowing lettuce ain't Rocket science.

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 14 Jan 08 - 02:24 PM

No bull, Charley?

Subject: RE: BS: Rocket Science???
From: Charley Noble
Date: 14 Jan 08 - 02:12 PM

What really surprised us, Art, was that when Cindy returned to earth she was not at all cowed by the experience, and after the press conference we got to milk the royalties for the film rights for years.

Cheerily,
Charley Noble

Subject: RE: BS: Rocket Science???
From: Art Thieme
Date: 14 Jan 08 - 12:57 PM

Udderly amazing tail---er, tale!

To ere' is human, to forgive, bovine!

Art

Subject: RE: BS: Rocket Science???
From: Charley Noble
Date: 14 Jan 08 - 09:37 AM

Art, that is certainly an amazing story.

It reminds me of one of my father's favorite stories from his years as a dairy farmer. We only had ten or so Jersey cows but they were quite productive. Part of the daily routine during the winter when the cows were sequestered in the milking "parlor" for months on end (we're talking about Maine here) was to shovel the cow manure down the trap doors, onto the manure pile fermenting below. Well, one day there was father down in the barn waiting for Dr. Pinfold to pay a visit to Cindy who appeared to be ailing. The good veterinarian was late so father decided to kill some time smoking his pipe, and after a while pried up one of the trap doors and shook out the ash onto the manure pile. There was one tremendous explosion as the methane gas ignited. The milking parlor was flattened, cows and father went flying. The newspaper headlines the next day proclaimed: THE FIRST HERD SHOT AROUND THE WORLD!

Cheerily,
Charley Noble

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 14 Jan 08 - 09:12 AM

Art, I happen to know that your story is God's own truth. MY uncle, who is no longer with us, happened to be flying past in his JN4J and saw you uncle, still reading, up in the air. My uncle asked him if he'd like a ride somewhere but your uncle just said "No, thanks, I've just lit my pipe and I've got a good book here."

Subject: RE: BS: Rocket Science???
From: JohnInKansas
Date: 14 Jan 08 - 04:12 AM

Now Art -

At first glance I was about to question your bit about "three hours later he came down."

On closer examination of the test conditions, however, it's quite obvious that the store of benzine in the innards of the the outhouse would have ejected a substantial exhaust plume, and uncle probably just sat up there on top of the plume 'till he finished the ladies garment section of the catalog, and then he hopped down all on his own.

(His comment about "somethin' I et" might have been a reference to a "bit of a burn" on the nether regions, from sittin' on that hot gas.)

The only remaining question is how much further into the ground did it drive the outhouse.

John

Subject: RE: BS: Rocket Science???
From: Art Thieme
Date: 13 Jan 08 - 11:34 PM

Once when we all went to town, one of the girls decided to surprise everyone by cleaning the whole house for us. She took at least three or four gallons of benzine and WASHED just about everything. She washed down the walls, and even immersed uncle Bud's pipes in the stuff and scrubbed 'em all out. Then she threw the left over benzine into the outhouse.

We got home about four PM. Uncle Bud had a new Sears catalogue and a new pipe and tobacco, so he settled down in the outhouse --- to light up and read the catalogue. He lit his pipe, tossed the match into the dark innards of the outhouse, and three hours later he came down in the middle of the chicken yard! We figure he must've gone a thousand feet up at least.

We ran up to him saying, "Uncle, Uncle, are you O.K.????"

He said, "Yep, it must've been something I et in town!!"

And that was that!

Art Thieme

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 13 Jan 08 - 04:39 PM

We used to make our own solid rocket fuel. I won't, for obvious reasons, give the ingredients here but will only say they were (and are) still rather easily available.

We melted them in an old electric skillet and poured the resulting mixture into the rocket bodies.

One flight was estimated (by inclinometer and slide rule) at 2,560 feet. Which wasn't bad for some kids using a city park as a launch site.

Subject: RE: BS: Rocket Science???
From: Charley Noble
Date: 13 Jan 08 - 01:52 PM

Wow! What jolly good fun!

Charley Noble

Subject: RE: BS: Rocket Science???
From: JohnInKansas
Date: 12 Jan 08 - 10:49 PM

In the realm of very real rocket science, I was present when a junior level manager came bouncing into the engineering office at "Little B Airplane" company gleefully announcing that "we passed the proof test."

The test article was a hollow spherical tank precisely 6 FEET in diameter, with walls 0.010 inches thick, that they had pressurized to "105% of design limit load" with "dry nitrogen," bringing the average stress in the container wall "to or above" 115,000 psi. The test was mainly to "proof" the weld that ran completely around an "equator" of the tank, to join the two hemispheres from which it was made.

Sufficient details are contained above for anyone with a sophomore engineering education to calculate the "compression energy" that would have been released had any failure occured. Hint: "more than 1,000 lb of TNT?."

They had performed the test during the main day-shift in an occupied building where approximately 300 people were busy building airplanes.

Had there been a failure, that building would have been gone, and the building I was working in some 80 yards away quite likely would have been "damaged beyond safe use."

I think it was remarkable, in fact nearly miraculous, that the the "manager" escaped without bodily harm - from MY OFFICE.

I'm quite sure that my remarks were not officially recorded in the Apollo Liquid Hydrogen Storage Tank Development Archives (Lunar Orbiter subsection).

John

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 12 Jan 08 - 09:37 PM

Gas? You want to discuss gas?

There are two easily obtainable white powders which, when mixed and kept dry, do nothing but sit there. Add water -- even just a drop -- and a chemically "dirty" batch of chlorine gas is produced and quite a bit of it, too!

My Late Mother's Three Big Rules:

1. You will no longer make pyrotechnics, fireworks, or explosives of any kind in the basement or anywhere in the house.

2. You will no longer make lachrymators or other war (poison) gases anywhere in the house.

3. If you are going to experiment with electricity don't trip the breakers.

Each was promulgated immediately after A Certain Incident.

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 12 Jan 08 - 09:27 PM

The US Army uses the following to simulated nuclear explosions:

Take a 55 gallon drum of jellied gasoline (although liquid will do in a pinch). In the bottom place a 1/4 lb. block of TNT, connecting via PETN detonating cord to a pile of 50 lbs. of TNT about 10 feet away. Double cap a couple of blocks in the pile with the PETN and run your wires from the block in the drum to detonator FAR away. Check the circuit and blow 'er at will. Gives a LOVELY mushroom cloud effect and you can (usually) reuse the drum.

Back in the day we were going to blow one of these off from an island in the Mississippi near town, just to get the town folks going. We were, of course, going to use a timed detonator.

Or just order the damn thing from the US Army supply system.

Subject: RE: BS: Rocket Science???
From: Jack Campin
Date: 12 Jan 08 - 08:42 PM

Nobody seems to have followed up on the question about poison gas.

When I was about 14 I had a heavy cold and was really bunged up. Tried mixing battery acid and glycerine for no reason I can remember. I did expect it to produce acrolein but didn't quite expect what acrolein does. It's a lachrymatory agent effective enough to use as a riot control gas. It got my nose streaming. In fact it cured my cold in minutes.

I got into official US government manuals about rocketry. Soon worked out that ammonium perchlorate and aluminium powder (detonated electrically by a fusewire loop from the mains) was going to be the safest and best bang I could get. Never tried to make a rocket but got some awesome bangs.

About 15 years ago I got the idea of doing O. Winston Link style photos of fishing boats offshore at night; I had a specific interesting and very remote location in mind. No electronic flash could do that, not even the sort of studio flashes they use for architectural work and advertising shots of cars. I asked on some photo newsgroups - turns out you can still get the sort of flashbulbs Link used, but the most interesting suggestion was to use the technology the US military employs for simulating nuclear explosions in battlefield exercises. Fill a trough with aluminium powder with an explosive charge underneath it and enclose it in a huge plastic bag filled with oxygen. The result is a flashbulb up to the size of a house. If I'd got round to doing it, it would have set off a flood of UFO reports from Skye to Ireland. I had no idea how to predict exposure, and since I'd only get one chance I would have needed to set up about a dozen cameras with different aperture settings, film speeds and filters to bracket the shot.

Subject: RE: BS: Rocket Science???
From: Rapparee
Date: 12 Jan 08 - 04:44 PM

My HS chemistry/physics teacher came into the Physics Lab one night (he was a Christian Brother and lived on-site) only to smell gas. In the dark he quickly opened all the doors and windows and turned OFF all the gas burner jets.

It shook him, because if he'd flicked on the lights the tiny spark would probably have blown out the walls of the room. The gas/air level was at critical.

Subject: RE: BS: Rocket Science???
From: JohnInKansas
Date: 12 Jan 08 - 04:17 PM

When Lin came crawling out of bed a few minutes ago, I noted my surprise at not being able to find anything on the web about the big Kip Kansas explosion. She went directly to her computer and pulled up an impressively detailed report. While she was still giggling over her ability to find something after I'd said there were no reports, I pointed out to her that the article she found, at Google, was "posted at mudcat.org 47 minutes ago." [see above]

Dang, but altering(?) history is s.o.o.o easy now!

John

Subject: RE: BS: Rocket Science???
From: JohnInKansas
Date: 12 Jan 08 - 01:34 PM

As a couple of "accidental experiments" have been recounted, along with some references to carbide cannons and such, the tale of the great Kip explosion might be of interest.

As a pre-note, as a high-schooler working at the family shop, I heard of a plan by a somewhat older employee who had found himself an old compressed air tank and was wanting to fill it with acetylene to take home to do some welding. I don't know where I had heard it, but warned him that compressed acetylene was not exactly "safe." I don't believe he ever really believed me; but he relented and got a commercial bottle.

The acetylene gas generated by mixing "carbide" (Calcium Carbide) with water technically is ethylene (C₂H₂) and when compressed to around 500 psi is "unstable" and can detonate - even without being mixed with any air or other oxidizer.

The name "acetylene" comes from the commercial practice of dissolving the ethylene gas in acetone, and as a dissolved gas, a cylinder can contain about 40 x the cylinder free volume of the gas at a fairly nominal pressure - usually not more than about 150 psi.

Some years after the above incident, an ex father-inlaw related numerous stories about his work at the Trailways Bus Maintenance Shop at Kip, Kansas (about 10 miles SE of Salina).

Among the many stories that we all heard until we didn't really want to hear them again, was the tale of the "last day" at the shop.

The Bus shop, as would be expected, had an acetylene generator. Details were never too precise, but it appeared to have been of the carbide-feed type, using a large cast iron "bell" that floated over the generated gas as a "pressure regulator." The "bell" was usually described as "600 pounds of cast iron" so I'd expect it was possibly 300 pounds, but that's still a fairly large capacity generator.

One fine day, someone noticed that the acetylene pressure was "very high and rising." An alarm was given and everyone "ran like h.- e. - bloody - HE**." Father inlaw claims to have been 300 yards down the road (I'll believe 100) when he was thrown another 50 yards (normal allowance, make that 20 feet) and "pieces of the shop flew past" (probably believable). Apparently the shop never resumed operation.

I have seen one picture taken after the event. Everything did look remarkably "flat." The picture apparently was a "private snapshot" and disappeared from known family records; and I've found no historical record of the incident. Small towns in Kansas abandoned after something exploded was not apparently newsworthy in the mid 1930s when (as I infer without documentation) all this happened.

What remains of Kip, KS shows on the map as 5 named streets, the longest of which about 240 yards and is apparently a dead-end in an open field. This might be where the shop was located, as it likely would have been built "on the edge of town" even then. The "town" - or what remains - is apparently too small to show any population statistics or to be noted in the history books.

[Current Washington State Safety Regulations (they were easiest to find) prohibit operation of an acetylene generator above 15 psi. The report by f.i.l was that the Trailways generator normally ran at 60 psi, although based on most of his other stories, he wasn't "good at math."]

John

Subject: RE: BS: Rocket Science???
From: Charley Noble
Date: 12 Jan 08 - 10:58 AM

This thread is being revived as a public service to folks such as Rowan who may have missed it the first time around.

Cheerily,
Charley Noble

Subject: RE: BS: Rocket Science???
From: HuwG
Date: 24 Sep 06 - 03:30 PM

Not strictly rocket science, but my little brother made himself a .177 cannon as a metalwork project at school (it was supposed to be a mantelpiece ornament, but what the heck).

We tried setting it off with the powder from a penny banger. The results were disappointing. With a hair-thin touch-hole, the thing refused to fire; when the touch-hole was bored out to about half the calibre of the gun, there would be a "poof" which left us blinking dazzled for several seconds. Meanwhile, the .177 airgun pellet which we used as ammunition remained firmly in the barrel. After we grew bored with extracting the pellets from the barrel, we concluded that there was some critical minimum aperture width, based on grain size or whatever. We thought that boring out the cannon to .22 calibre might have some effect, but the parental and educational authorities had by now twigged the significance of the drill bit sizes my little brother was using.

Friends of ours discovered that secretly removing an inch or three from the stick of a large firework rocket could sometimes enliven firework displays; as could surreptitiously leaving unopened tins of baked beans among material being collected for large local bonfires.