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Registered Member #30
Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
Dr. Slack wrote ...
So why does a rare earth magnet flash when you crunch it?
The rare earths all spark when you grind them. Lighter flints are made of "Mischmetal" which is just a mixture of all the rare earths unseparated. They used to contain neodymium before it got more profitable to extract it for making magnets.
Registered Member #1334
Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615
cduma wrote ...
I made a 80:30 mix of FeO2 and Al and place it ontop of my HDD lit it and ran. Fire, smoke and molten metal follow...
quicksilver wrote ...
...Why in Heavens did you RUN when you lit the thermite? You can't see what's happening if you run.
Sometimes running is an extremely good idea...
and (another recording this time from a camera phone
My youngest son filmed the first one from about 5 metres away. If you listen carefully you can hear someone saying "run away" and can see a brick end flying past the camera at the end... Nothing was left except a dent in the ground and a faint smudge of what might have once been pumpkin. Flaming bricks were found some distance away but amazingly no-one was hurt and no cars damaged. A few people had small burns on their clothing... It seems thermite is now banned from UK teslathons...
Registered Member #607
Joined: Tue Mar 27 2007, 10:39AM
Location:
Posts: 64
Quicksilver... Re Nicko's links to Youtube. Preperation & planning is the key, not running. If in doubt, my advice is to never EVER burn thermite through an object, sealed or otherwise, without knowing what reaction you'll get from the individual components within. The reaction in this case was expected, but the setup was flawed. This was not done at the Teslathon per se, but afterwards. Nonetheless, it hasn't been repeated that I'm aware. And rightly so. Been there, seen that etc is enough for me.
One suggestion form a once fellow coiler the previous year was to cast something with thermite. Would make an unusual art piece. Not so exciting maybe, (depending upon your viewpoint) but just as interesting.
Registered Member #607
Joined: Tue Mar 27 2007, 10:39AM
Location:
Posts: 64
Steve... "Disaster" might be an overstatement. (IMHO) Thoughtless and with hindsight, dangerous without a doubt. However, it does bring home (and that was my previous point) that if you're dabbling with the unknown & unseen or lack experience, expect the unexpected. Then plan for it plus an extra margin. (The "extra" was missed in that particular case.) That's why I now race a 380BHP bike. Soooo much safer... I know, I see and I have experience. And it only involves myself. Cheers...
Registered Member #3040
Joined: Tue Jul 27 2010, 03:15PM
Location: South of London. UK
Posts: 237
A thermic lance will melt pretty much anything. Easy to build but you need an Oxygen cylinder. Running is never a good idea, if you think you may need to run then it's probably best to ignite it remotely and make sure everyone is at a safe distance. Hand lighting fireworks for public displays is dying out and for good reason, a company in the UK recently had an incident where a crew member nearly blew his hand off, they have now banned hand lighting.
Registered Member #902
Joined: Sun Jul 15 2007, 08:17PM
Location: Pacific Northwest USA
Posts: 1042
Martin King wrote ...
A thermic lance will melt pretty much anything. Easy to build but you need an Oxygen cylinder. Running is never a good idea, if you think you may need to run then it's probably best to ignite it remotely and make sure everyone is at a safe distance. Hand lighting fireworks for public displays is dying out and for good reason, a company in the UK recently had an incident where a crew member nearly blew his hand off, they have now banned hand lighting.
here in the US hand lighting is still widely used for non-automated shows - we just use a long stick with a road flare attached as well as procedure (gave us about four extra feet from our hands to the fuse). I personally like to use a Long Handled Propane Torch (available for about $40 and gives an extra three feet, but it is electronically lit has an adjustable flame and most importantly you can turn it off, then back on which is useful for shells that don't go off or in my case a 600 shot cake that didn't light during the finale electronically)
also, most shooters I know are trained initially to hand light because it is still common and needs the most training, and you learn more in the process including a true respect for the power of 1.3g fireworks.... some people I know even hand lit 6 inch shells, though they do so no more thanks to electronic equipment but they still hand light 3's and 4's.
BTW: in the UK, so you still have above 8 inch shells rated to the equivalent of our 1.3g (display grade fireworks?) - in the US they've been deemed higher explosives, available only to those under the Grandfather Principle or with an even higher explosives license
Happy Shooting! I hope to have my Operators License in a few years time, otherwise I'll have to use loopholes in the system all of my life
Registered Member #3040
Joined: Tue Jul 27 2010, 03:15PM
Location: South of London. UK
Posts: 237
DaJJHman wrote ...
... also, most shooters I know are trained initially to hand light because it is still common and needs the most training, and you learn more in the process including a true respect for the power of 1.3g fireworks.... some people I know even hand lit 6 inch shells, though they do so no more thanks to electronic equipment but they still hand light 3's and 4's.
BTW: in the UK, so you still have above 8 inch shells rated to the equivalent of our 1.3g (display grade fireworks?) - in the US they've been deemed higher explosives, available only to those under the Grandfather Principle or with an even higher explosives license
Happy Shooting! I hope to have my Operators License in a few years time, otherwise I'll have to use loopholes in the system all of my life
-Jimmy
I have been trained in handlighting and have handlit small shows in the past. We still occasionally handlight "safe" pyro purely for performance reasons (most of our shows aren't just shell chucking, they involve live performance, lighting, projection etc. etc.) and we will sometimes handlight as a backup for a failed igniter but that is usually too dangerous due to site layout. Larger shells are becoming an issue, the largest I've done is 16" and that's quite possibly the last 16" shell fired in the UK ? Unfortunately it burst low and blew the windows out of the lighthouse it was next to (looked great though). We don't have licensing for firer's in the UK for cat 4 fireworks you need insurance and licensed storage and that's about it.
Registered Member #1334
Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615
Martin King wrote ...
...Larger shells are becoming an issue, the largest I've done is 16" and that's quite possibly the last 16" shell fired in the UK ? Unfortunately it burst low and blew the windows out of the lighthouse it was next to (looked great though).
Was this you too?
So, apart from blowing up the lighthouse & burning down the pier, it was a great show
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