Shop OBEX P1 Docs P2 Docs Learn Events
best way to get a couple thousand degrees consistently on the cheap? — Parallax Forums

best way to get a couple thousand degrees consistently on the cheap?

P!-RoP!-Ro Posts: 1,189
edited 2010-08-09 21:32 in General Discussion
I have powdered aluminum foil and rust swept off the floor of a metal shop and I need to make thermite, preferably set off digitally. I would like to keep it cheap since I don't have much money, but I have plenty of time to make what I need. A small torch just won't cut it, but I have no money to buy a new one powerful enough for what I need. I've tried using my 110v stick welder and it didn't work, I blamed that on the electricity destroying my rust. Anyone have a better idea for setting this stuff off? I'm clueless and broke. I was hoping to make a thermite engine eventually...

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
90 * 2 = Pi
«1345

Comments

  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2010-07-30 05:58
    Thermite isn't going to make you popular with Homeland Security, but if you must....

    HOW TO PORTION OF TEXT REMOVED by Loopy
    >
    >
    >
    >

    Do yourself a favor - forget this project. A thermite engine is a contradiction in terms as the heat will melt the engine block.

    And both kids and adults, this stuff is extremely hot and dangerous. Don't do this without sane, adult supervision (normal adult is not enough).

    I personally feel that Parallax should just implement a 'Don't ask if it is dangerous and stupid policy'. Feel free to remove this posting or to ask me to do so. This forum is not about getting one's self hurt. And it isn't about chemical reactions.

    These days, I strongly suspect that 'aluminum power' is a a Terrorist Materials Watch-list. So you may have a heck of a heap of trouble if you try to buy it without a good reason for needing it.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Ain't gadetry a wonderful thing?

    aka G. Herzog [noparse][[/noparse] 黃鶴 ] in Taiwan

    Post Edited (Loopy Byteloose) : 7/30/2010 6:20:55 AM GMT
  • mctriviamctrivia Posts: 3,772
    edited 2010-07-30 12:09
    thermite is cool stuff but as Loopy said it is just way to dangerous and if you do not know how to do it then you should not be plying with it.

    The only hint I will give you is that if you want to play with it you will find your answer if you take a pyro technics coarse and take a few university chemistry classes.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Lots of propeller based products in stock at affordable prices.
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2010-07-30 12:57
    "A small torch just won't cut it..."· smile.gif

    Anyway.

    Is that "a couple thousand" Fahrenheit or Celsius?
  • edited 2010-07-30 13:27
    A relative gave me an article years ago called "The Day I blew my fingers off". I wish I still kept it.
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 13:55
    @loopy-I'm 17, I'll do all right. [noparse];)[/noparse]
    The only reason thermite is dangerous is the quantity. Here is a video of a nice 100 gram reaction:
    www.youtube.com/watch?v=D0YWV3nHD-g

    If it burned on top of salt it would melt it and protect any fire cement from the extreme heat. It would also allow me to store this heat so I could use it.

    Some other good things about thermite:
    - it's safer than gas
    - can allow machinery (robots?) to work in areas of extreme heat without high explosive risk
    - 3x more power per volume than tnt with only fractional more weight
    - recyclable by-product and all the ingredients are already used in the military
    - NON EXPLOSIVE

    But either way I'll figure it out, it's perfect for my application (which is a first as well).
  • Mike GreenMike Green Posts: 23,101
    edited 2010-07-30 15:07
    Wrong! Small quantities of thermite are dangerous because of the amount of energy released once triggered. Larger amounts of thermite are very very dangerous for the same reason. It sounds like you have an insufficient appreciation of just how dangerous it can be, even in small amounts.
  • RickBRickB Posts: 395
    edited 2010-07-30 15:24
    What material will you use to contain and enclose the reaction? It can reach about 4500 deg. F.
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 15:34
    Wrong about what? I never said it wasn't dangerous. But since it's exothermic, regular welding gear will be protective of the sparks, and sunglasses will protect from the light!

    But seriously, fire burns at 1200 deg. F and thermite burns at 4500. I'd probably compare 100 grams to using a plasma cutter or 120 amp stick. I've done both and with proper precautions hopefully thermite won't burn my toes like stick usually does [noparse]:)[/noparse]

    As for using cement for the engine I need to watch for 3 things:
    - capable of expanding with the heat and not cracking
    - outlet for sudden pressure change due to heat
    - sufficient spread of heat with material such as molten salt to prevent temperatures above toleration of the cement
    - careful preparation of the engine chamber to prevent gas bubbles in the cement which could cause it to crack or explode

    Once all this is done it should hopefully be semi-safe like any gasoline engine.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    90 * 2 = Pi
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-07-30 16:21
    pi'd said...
    ... I'm 17, I'll do all right....

    Why does that sound like a quote from one of those Burned Beyond All Recognition films I was shown in military safety school?

    pi'd said...
    ...
    ....The only reason thermite is dangerous is the quantity....

    Why does this quote remind me of T. K. Jones, a Deputy Undersecretary of Defense under Ronald Reagan, who told us that nuclear war was not nearly as bad as the news media made it sound. He said, "If there are enough shovels to go around, everybody's going to make it." The shovels were for digging holes, which he told us we could cover with doors and throw about three feet of dirt on top.. "It's the dirt that does it," he said.

    pi'd said...
    ...
    Some other good things about thermite:
    .... all the ingredients are already used in the military...

    And therefore it's inherently safe? WTF?
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2010-07-30 16:29
    I think you are quite wrong about 100 grams of thermite being safe.

    If you really want to explore such, just talk to a Marine or Army recruiter and they will get you into learning all about explosives.

    For instance...

    Did you know that some of today's hand grenades use thermite rather than other explosives?

    Did you know a modern mortar is propelled by nitroglycerin?

    What's wrong about it?
    Cement is unlikely to survie 4500*F, you need a refractory ceramic. And the water in concrete will like cause popping and explosions as it breaks down.

    Engines use fuel under a controlled explosion. Thermite is so hot that containment is likely to end in drastic failure (a big explosion with shrapnel).

    If you want to study engine design, there is quite a body of good information (Like discussing the Carnot cycle - http://en.wikipedia.org/wiki/Carnot_heat_engine).
    Can you apply that to your fuel?

    Thermite is far, far more heat intense that a gasoline engine operating at 350* F. Don't kid yourself. You want an excuse to play with explosive force, not any constructive engine design.
    If your are really interested in engine design, the future seems to be in conversion to methane from gasoline and diesel. And bio-methane is a big challenge (made from pig and chicken (expletive), because it is up to 50% CO2 combined with the methane).

    You are never going to see a fuel distribution system for Thermite as it would far worse that Molitov cocktails in the wrong hands; and it take tremendous energy resources to produce the aluminum and iron in pure forms. And the other hand, we have abundant and under-used resources of methane.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Ain't gadetry a wonderful thing?

    aka G. Herzog [noparse][[/noparse] 黃鶴 ] in Taiwan

    Post Edited (Loopy Byteloose) : 7/30/2010 4:59:32 PM GMT
  • edited 2010-07-30 16:37
    pi'd said...

    If it burned on top of salt it would melt it and protect any fire cement from the extreme heat. It would also allow me to store this heat so I could use it.
    pi'd,

    What exactly is fire cement?· Is that·like tiles on the space shuttle?· My parents had a wood stove and the cement blocks loosened and we weren't the manufacturer so it was difficult to glue them back.· The heat also·cracked the blocks from a regular fire.

    Fire is a dangerous thing.· Commercial buildings have to have a fire wall and there is an assumption that they can handle fire for a half an hour or whatever they assume the walls can handle.· After that, they expect the structure to collapse.

    To an untrained eye, what you want to do is only something that companies train and prepare to do.· They get permits to do these things and fire ratings are based on MAQs (Maximum Allowable Quantities).

    I don't want to hurt your feelings but if you have to ask the question then it is because you don't have experience with this and even people with experience get hurt.

    Chuck
    ·
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2010-07-30 16:43
    Fire cement is not rated for 4500*F. You need to study refractory materials used in the contruction of a steel mill, and beyond. Special ceramics. And they don't last very long, not long enough for an 'engine'.

    Railroads use thermite to weld continuous rail track. And when I worked in nuclear reactor construction (on the Hanford Nuclear Area - home of the first A-bomb), we used it to weld rather huge concrete reinforcing bar. But under those conditions IT WAS NEVER CONTAINED under pressure and only a crew of two people were allowed within 50 feet of it.

    I used to make explosives when I was a kid. I was even amazed when the pharmacist at the local drug store would sell me ingredients. I've had my share of close calls, including having something blow up in my hand and it being numb for months.

    Later when I was in college, I met a guy in a pub that had no fingers on one hand. Since we were drinking beer the topic turned to how he lost all his fingers. His reply was that he made his own explosives as a kid. From there, we went into a rather long evening of discussing what he may have done wrong. He took all the precautions that I knew of.

    In sum, I have been very lucky; he wasn't so lucky.

    If you really study the Chemistry, you will find that some mixtures just happen extremely fast and cannot be controlled as a fuel. That is the nature of explosives, including thermite under pressure.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Ain't gadetry a wonderful thing?

    aka G. Herzog [noparse][[/noparse] 黃鶴 ] in Taiwan

    Post Edited (Loopy Byteloose) : 7/30/2010 4:55:56 PM GMT
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 16:44
    Then I'll blow myself up trying. But seriously I made this post because I'm going to try it and I was hoping to find the best way to do it. If not I'll learn the hard way.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    90 * 2 = Pi
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2010-07-30 16:46
    And my dear grandfather always said, "Most people in the graveyard had the right of way."
    I am not the only kid that blew himself up thinking I knew enough to be safe. Not even the only kid in my high school.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Ain't gadetry a wonderful thing?

    aka G. Herzog [noparse][[/noparse] 黃鶴 ] in Taiwan

    Post Edited (Loopy Byteloose) : 7/30/2010 4:56:29 PM GMT
  • sylvie369sylvie369 Posts: 1,622
    edited 2010-07-30 17:22
    pi'd said...
    Then I'll blow myself up trying. But seriously I made this post because I'm going to try it and I was hoping to find the best way to do it. If not I'll learn the hard way.

    And in your first post you wrote "I'm clueless and broke". Does that really sound like you're on the road to accomplishing something?

    Whose property are you doing this on?
    What precautions have you taken to prevent fire from spreading?
    Which adults have you told your plans to (in real life, not on the internet)?

    If you can't walk right up to your parents and tell them what you are trying to do, then you know full well that you shouldn't be doing it.

    You can tell us that you've told your parents, and we'll never know the difference. But you know that you haven't told them, and you know exactly why you haven't.
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 17:45
    Yeah they know, and my dad had a rant on how dangerous powdered aluminum was...but that's to be expected. Thermite really isn't too bad. Nothing compare to blowing up a butane can and yelling at a friend who caught himself on fire trying to get it to explode faster [noparse]:)[/noparse] Now that one I haven't told to my parents!

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    90 * 2 = Pi
  • mctriviamctrivia Posts: 3,772
    edited 2010-07-30 18:08
    pi'd. You are being stupid.

    1) Termite is extremely dangerous. It will not explode itself but it will cause one if in a pressurized container or near any material that can be vaporized to rapidly by the heat(water)
    2) You do not have a pyrotechnics license and do not have an adult with one helping you. I know this because from working with rockets and pyrotechnics I know your first question "how to safely ignite termite" is super easy if you have the knowledge needed to get your license(and you have to be 18 in most countries)
    3) You are not willing to listen to reason from older people with more expeierence with knowledge of electricity, explosives, and general enginering skills which you should learn for your self before attempting anything like this.


    If you really want to play with fire and explosives wait until you are old enough and take a pyrotechnics course. It is not expensive and you can get part time work doing theatrical productions to make money and get experience on how to do things correctly.

    I have played with termite, and made small explosives but I have only ever ignited them in large fields with no flammable objects(not hard to get permission to do at small air fields if you have the write papers). I have always been at least 50m away and have taken all safety precautions to make sure it could not go off before I wanted it to.

    Don't be impatient. you can play with fire. you can play with explosives. You just need to get the necessary training and licenses first so you do not hurt yourself or anyone else. Your lack of knowledge can kill and it may not be you.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Lots of propeller based products in stock at affordable prices.
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 18:34
    wiki.answers.com/Q/Is_Thermite_Illegal_to_own_in_the_US

    That's the best article I could find in my 5 second search. I may be stupid but I'll listen to safety tips if they come my way, but mostly all I'm hearing is to not do it which is not an option.

    The military doesn't use thermite for it's explosive properties, they use it because it's hot. Normally, small amounts of it are packed with explosives so when it explodes there is a heat aspect to it as well. The closest thing to thermite and explosives that I can come up with is the new style of flash grenades which have powdered aluminum packed in a tight space and when the reaction starts it is blown out and ignited, creating a lot of light and sound as the air suddenly expands. It isn't very dangerous though, mind.

    EDIT:

    I'm planning to use it in a fire pit surrounded by green grass on my own property (my dad is okay with it, mind).
  • mctriviamctrivia Posts: 3,772
    edited 2010-07-30 18:48
    www.youtube.com/watch?v=lAEBlJQkEdM

    Safety tips:
    1) find a way to electronically detonate from a long distance
    2) Have a blast shield in front of you made of lexan
    3) have licensed explosives export with you

    These are minimum safety requirements.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Lots of propeller based products in stock at affordable prices.
  • edited 2010-07-30 19:05
    Man's hand blown off in illegal fireworks accident in Oakland

    http://www.mercurynews.com/breaking-news/ci_15448063?nclick_check=1

    I also watched a fireworks display on the 4th of July.· They stopped and were delayed for about 9 minutes for a fire on the ground.· We saw smoke and an orange glow.· Even the "professionals" have problems.
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 19:09
    The thermite just causes the gas in the ice to expand throwing pieces everywhere. It's also a good reason to test and test again to ensure the materials in my engine are strong and durable. Just getting a reaction going, however, is harmless. I'll worry about the safety measures when I want it in an engine. I won't be using that much thermite either though, mind. It would be like getting your car to guzzle a gallon in a couple seconds!

    BTW--in case you hadn't noticed, I don't believe in what the say is the water turning into hydrogen and oxygen and then exploding. If that happened, it would create a sonic boom and be instantaneous due to the mixture, unlike this reaction. I think it's just molten metal thrown everywhere by the steam.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    90 * 2 = Pi
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 19:10
    @Chuck --isn't it just amazing what black powder can do?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    90 * 2 = Pi
  • edited 2010-07-30 19:15
    pi'd said...
    @Chuck --isn't it just amazing what black powder can do?

    It doesn't discriminate.· My brother in law works for a defense contractor and he had to read a two foot pile of books on static electricity.· Lets say you want to make rocket engines and you have to make a cake mix and you're going to use motors to mix the cake.· You're using electricity.· Uh· oh.
  • davejamesdavejames Posts: 4,047
    edited 2010-07-30 19:29
    ...hmmmm, sounds to me like 2010's candidate for the Darwin Award.

    DJ

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  • P!-RoP!-Ro Posts: 1,189
    edited 2010-07-30 19:33
    @Chuck--I'm not quite sure of what you're saying's relation to thermite...

    But one thing I do want to note is this thread is really starting to irritate me. It's not because of anything recent, it actually spawns back to when I was at the Parallax expo in June. I was talking to Peter Van der Zee and he was telling me that the thing that really annoyed him about helping others on these forums was when people would ask for advice and not listen to what he has to say. I told him I tried not to do that, and ever since I've tried even harder. But yet here I am on this thread with people telling me I shouldn't do something of which I've had on my mind for months, telling me it isn't possible. The reaction here is similar to what Peter said he disliked, but at the same time it is advice I don't ever recall asking for. I really respect all that you have to say, but it isn't going to stop me until I know for sure it won't work. As far as I know, that means making thermite and making an engine that won't break with the heat and will be safe. If you can help me with that, I will listen. Otherwise, just keep in mind I will try it and try to be safe regardless of whether you call it too dangerous.
  • HollyMinkowskiHollyMinkowski Posts: 1,398
    edited 2010-07-30 19:34
    I just watched an episode a few nights ago of a TV series
    I had on my HD but had never started.

    It's called "Breaking Bad", and in one episode the main character
    (a brilliant chemist with a bad prognosis for lung cancer ) makes
    thermite from scratch and burns the lock off of a warehouse door.
    He also made something called fulminated mercury and blew up
    the office of an insane drug kingpin with a chunk of it.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    justasm.blogspot.com/
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-07-30 19:37
    pi'd said...
    .... I think it's just molten metal thrown everywhere by the steam.

    Including into your eyeballs. And the frontal lobes of your brain.


    Things don't have to be classified as explosives to create explosions. As you yourself have just mentioned, the moisture inside anything can rapidly expand when heated to steam. This includes the moisture in rocks and soil, ceramics, etc. What happens if the material upon which your thermite is resting blows apart from the rapidly expanding steam and yet the thermite is still hot as hell when it splashes into your face?

    Also just because you might use "electronic ignition" at a distance doesn't make it safe. When I did explosives work, we always had to monitor for radio waves, electrostatic build-up etc. using fancy instruments so we reduced the chances of maiming and killing everyone involved.

    Teenagers and explosives: Darwinism in action?
  • edited 2010-07-30 19:47
    pi'd said...
    @Chuck--I'm not quite sure of what you're saying's relation to thermite...

    But one thing I do want to note is this thread is really starting to irritate me. It's not because of anything recent, it actually spawns back to when I was at the Parallax expo in June. I was talking to Peter Van der Zee and he was telling me that the thing that really annoyed him about helping others on these forums was when people would ask for advice and not listen to what he has to say. I told him I tried not to do that, and ever since I've tried even harder. But yet here I am on this thread with people telling me I shouldn't do something of which I've had on my mind for months, telling me it isn't possible. The reaction here is similar to what Peter said he disliked, but at the same time it is advice I don't ever recall asking for. I really respect all that you have to say, but it isn't going to stop me until I know for sure it won't work. As far as I know, that means making thermite and making an engine that won't break with the heat and will be safe. If you can help me with that, I will listen. Otherwise, just keep in mind I will try it and try to be safe regardless of whether you call it too dangerous.
    I'm not asking for advice.· I'm giving advice and I can't stop you from doing what you want to do and I can't stop you from encouraging other people as well.· Your project isn't for everyone.· I'm sure you have a rational for what you are doing but it isn't shared with everyone.· I know if I got in trouble doing something like this the authorities would say I was risking a catastrophy, I lacked the proper permits, I put people at risk.· If you went to get a permit for what you were doing, what do you think the authorities would say?

    The advice I would give people, "When in doubt, do without."·
  • Erik FriesenErik Friesen Posts: 1,071
    edited 2010-07-30 20:11
    I can understand how you feel about this, I have tried stuff I wouldn't try now. What I have to say is this - Find a book, don't do your research on the net, and learn everything you can about it. If you can find someone that knows about it, talk to them. There are hidden danger with many things that are not perceived at first. For example, talk to a tree feller. What looks to be a simple process is fraught with danger, as many experienced tree fellers with head injuries can attest.
  • pjvpjv Posts: 1,903
    edited 2010-07-30 23:38
    Hi Pi'd;

    Well, I for one encourage you follow your passion, and experiment with the thermit process to your heart's content..... it is relatively safe because it is not "explosive" in its own right; after all, we did it in the classroom at school. It does generate a lot of heat however, and that can have secondary effects, so just do it as safely as you can, and do advise your parents as to what you are up to. After all they are still responsible for your well being, and to hide your activities from them would be irresponsible. Better yet, have them involved or observe your experiments and ask them if they think your set-up is safe enough. I believe that was how Ken and Chip Gracey were tought with their experimentation.

    The thermit process is relatively harmless unless you are reckless, and in that case you should not experiment with anything potentially dangerous..... I recall a high school student cooking mercury fulmanate up at home in his mother's oven. Now, THAT's recklessness.

    As far as permits are concerned, my view is that if we all followed the safest path possible, nothing would get done, and nothing much new would get discovered. Imagine Columbus or Franklin, or Tesla, Edison worrying about such things....... just weigh the risks and don't take STUPID chances. Our governments and military will take those for us...... imagine, inventing an atom bomb and edging us toward anihilation, and we should worry about thermit?

    Sorry about the rant, but I have some difficulty with the croud that wants to wear crash helmets to bed to protect you in case you should fall out.

    Cheers,

    Peter (pjv)
Sign In or Register to comment.