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belfrybat
2nd May 2013, 21:48
Teen faces felony charges in exploding water bottle incident; was it a science project gone bad? - ABA Journal (http://www.abajournal.com/news/article/teen_faces_felony_charges_in_water_bottle_incident_was_it_a_ science_project/)

500N
2nd May 2013, 22:00
Christ, if that is all it takes to get expelled, I and quite a few of
my mates would have been hung, drawn and quartered for
what we got up to. As it was a very sore backside.

(Welding flux and sugar + 240 volts of electricity, big bang
and plenty of smoke).

belfrybat
2nd May 2013, 22:10
The bottle didn't even explode, just popped the top.

In my early teens we got hold of a bag of saltpeter. The sulphur and charcoal were easy to find. Mostly hiss, sparks and billowing clouds of smoke but we did get some nice bangs too. We did take care to experiment in an old quarry far from civilization and didn't get in any trouble over it, not even a burnt finger.

tony draper
2nd May 2013, 22:15
Saltpeter? we used to go into the corner Chemist shop and buy it over the counter,also a bag of flowers of sulphur,the charcoal we made ourselves.
:)

Fox3WheresMyBanana
2nd May 2013, 22:15
I was once told by an individual that he built a rocket at 15. It was designed to reach 50,000'. Due to (he now estimates) poor packing, it reached approx. 1,000' before exploding. Apparently the local Police still have an open file on this one 40 years later - the bang was that loud.

He is now Professor of Chemistry at a well regarded University.

500N
2nd May 2013, 22:18
"We did take care to experiment in an old quarry far from civilization and didn't get in any trouble over it,"

That was out mistake We did it in our study at School, filled the study
and the whole hallway full of white smoke :O (Oh, and burnt a hole
in the polished Parquetry floor which is how they found out).

TWT
2nd May 2013, 22:31
When I was at school,we put a rock of calcium carbide into an empty one gallon paint tin,wet it,jammed the lid on and then laid it on its side.A match was held to a tiny hole pricked in the base of the tin and kaboom !,the lid shot off.

We did this multiple times after school and the school principal even came for a look on the first day and walked away,saying nothing.How times have changed.

tony draper
2nd May 2013, 22:40
Amateurs,try potassium permaganate and conc hydrogen peroxide.:E
If we just wanted bangs we had Railway track detonators.
:)
Calcium carbide plus water = acetylene gas Mr TWT
We used to get our Carbide outside the pit where the miners emptied their lamps

Ozzy
2nd May 2013, 22:57
In a chemistry class I poured nitric acid into the middle of a mate's exercise book...no fuss involved but his book was destroyed ha ha! Also played games with bunsen burners...oh how we laughed...

Ozzy

Davaar
2nd May 2013, 22:59
we used to go into the corner Chemist shop and buy it over the counter,also a bag of flowers of sulphur,the charcoal we made ourselves.


... and in those days it was quite easy to get spent .303 cartridges. Several of these could be filled with the g******* and put into an old tin biscuit box.
Buried in a snow-drift with e wood fire built over the top-lid there was an interesting wait for developments.

The carbide was s.o.p for lighting bicycle lamps.

TWT
3rd May 2013, 00:05
Calcium carbide plus water = acetylene gas Mr TWT

Indeed Mr.Draper.It also produces calcium hydroxide.

( which I didn't know until consulting Wiki just now)

UniFoxOs
3rd May 2013, 07:39
In my early teens we got hold of a bag of saltpeter. The sulphur and charcoal were easy to find.

Same here - could never get more than a fizz out of the mixture. Then a mate told us about sugar and weedkiller. He used to pack this into offcuts of 1/2" copper pipe, squeeze the ends flat in a vice, and toss them into people's bonfires on Noveber 5th.

So we made some similar and set them off by balancing them on top of an old tin can with a drop of meths in it. Light the blue liquid and retire immediately. Very satisfying bangs. All was well, village was mystified at the strange noises, until my mate managed to set one off during manufacture and blew his hand apart. I was gated for a month after that.

UFO

angels
3rd May 2013, 07:48
Shot in Face during Firework Fight - YouTube

The guy with the long hair seems to be Winchester after just two shots, but firework war is cruel....:E

Msunduzi
3rd May 2013, 08:10
Freedom? Liberty? Justice???

Do the school staff have such low self esteem that they can not handle something like this?

Maybe they think they will get brownie points by making a big fuss, and destroying the kids future.

Fox3WheresMyBanana
3rd May 2013, 11:57
School staff have, in far too many cases, no faith in their senior managers (or Principals in their education board/authority).
So, to preserve their jobs, everybody becomes a stickler for the rules.
Whilst I despise the individuals who take these actions, I recognize that they are part of the symptoms, not the cause.
It is to the education boards and education ministries/ministers that complaints must be addressed- they set the system and the culture.

MadsDad
3rd May 2013, 14:49
I do recall dropping lumps of Carbide into the road drains then following this by a lighted match. Had an interesting effect on the drains in the vicinity.

Mind you I also recall a kid I was at school with (son of one of the local village coppers) who made TNT and then would sell it on - a half-pint bottle would have been 10/- but I don't recall anyone brave enough to try it. Definitely not me. But the kid claimed to have several pint bottles of the stuff buried in a nearby dam.

OFSO
3rd May 2013, 17:23
A 6kW transmitter on top band fed from the mains in Enderby (Leics) which you could FEEL in your bones if you walked past the house and the morse could be read from the blipping of the street lamps. Escalation to 12kW caused a small fire and a visit from the police. What has happened to the equivalent of these adventurers today ? All feffing about on Farcebook, no doubt.

Msunduzi
3rd May 2013, 17:42
6kW is less than an electric shower (10kW) and the streetlights certainly don't dim when they are turned on.

An average 2 bar heater is 2kW, and many houses would have one.

In an urban environment, 6kW on CW would be a total waste of time, how are you going to hear the other station?..

As it is more than 10 times the legal limit, it is almost certain that more than the local bobbies would get involved.

VP959
3rd May 2013, 17:59
6kW is less than an electric shower (10kW) and the streetlights certainly don't dim when they are turned on.

An average 2 bar heater is 2kW, and many houses would have one.

In an urban environment, 6kW on CW would be a total waste of time, how are you going to hear the other station?..

As it is more than 10 times the legal limit, it is almost certain that more than the local bobbies would get involved.

Shame that you have made a seemingly technical reply that merely illustrates a woeful lack of understanding of the effect of high power RF on gas discharge lighting..........................

As anyone who's played around with HF at this sort of power level may well have observed, the field strength is quite strong enough to light up discharge tubes, or modulate their brightness.

There's also the efficiency to take in to account. Vintage HF PAs struggled to get better than around 20 to 30% efficiency, so that 6kW could easily be 20kW or more drawn from the mains (and yes, HF PAs back then were quite toasty devices).

421dog
3rd May 2013, 18:23
Several old 12kv .1f PCB filled capacitors, a box full of xenon bulbs from an experimental approach lighting system (that was reportedly too bright), a home made power supply and a coil or two to make it all flash.

You could feel the thing go off from across the room.

We could never make a reliable electronic trigger because the induced current just fried any solid state component that got near it.

Oh, and God help anyone who even looked at the reflection off a white wall.

CY80
3rd May 2013, 18:42
When i was a kid (back in Russia), i used to make electric shockers out of massive capacitors and bully my classmates. Smoke bombs out of ping pong balls, rockets and bombs out of Ammonium nitrate... when we couldn't get some of the stuff described above then we used to dismantle AK-47 bullets (apparently they were easy to find) and make bombs from the gun powder... but when we were totally desperate we just used to light small Propane cylinders on fire, those were fun but took ages to heat up.

And here i am, 20 year later, law abiding citizen with 2 kids and a small business. This world is bizzare.

belfrybat
28th May 2013, 16:14
Girl expelled from school for exploding experiment going to space camp (http://www.space-travel.com/reports/Girl_expelled_from_school_for_exploding_experiment_going_to_ space_camp_999.html)

cockney steve
28th May 2013, 23:00
Anyone remember the old Harpic bog-cleaner tins? (It was probably justCaustic Soda crystals, but we didn't know things like that, then.
As the proud owner of a Carbide bike-lamp, which I had got working, I had a supply of Carbide. Oddly enough, the container was very similar to the Harpic one, in size, if not colour.

Take Harpic tin , pour in an inch of water. Get a big dollop of axle-grease and plaster into screw -cap....embed several chunks of carbide into grease....invert cap and screw onto tin.....walk to bottom of garden, invert tin, ram into flower -bed and leg it. a few minutes later a satisfying BOOM ! followed by PING.P- P -P ping as the lid richiochetted around the apple-trees.
ISTR the neighbours complaining about this, the version wrapped in a flaming paraffin-soaked rag and various other pyrotechnics.
It got banned, or I grew out of it for a while.:)

Yamagata ken
29th May 2013, 03:08
Captain Draper Saltpeter? we used to go into the corner Chemist shop and buy it over the counter,also a bag of flowers of sulphur,the charcoal we made ourselves. Precisely. I still remember the elderly chemist (not Pharmacist) smiling benignly from behind his half-moon glasses as he handed over the makings to my brother and me. Big brother had made a muzzle loader in his school metalwork class, bored, tapped and plugged with a grub screw. We had a supply of about 10mm ball bearings. It worked well, very loud bangs and no problem punching holes throught the corrugated steel fence at the bottom of our garden.

radeng
29th May 2013, 14:31
VP959,

You could do a lot better efficiency in the PA - it would be the rest of the tx that pulled it down. I got about 77% efficiency in a PA running about 200 watts input to a single 807 with about 1500 volts on the anode , 350 on the screen and about 200 volts negative on the grid. Then driven hard with a 6L6G. Happy days on 40m CW....So it should have been possible to get an overall efficiency of about 45%. Of course, OFSO didn't say if it was 6kW in or out!

finfly1
29th May 2013, 14:44
My own experiment with calcium carbide (if a little rock does that, what would a whole handfull do) resulted in my cleaning massive amounts of black soot off the cieling of our chemistry lab after normal school hours.