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LAN_403

Omicron

Sat Feb 18 2006, 09:40PM

Registered Member #131 Joined: Fri Feb 10 2006, 09:25PM
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Posts: 185

Just be safe the stuff burns at about 4000 degrees

Jim

Sun Feb 19 2006, 04:22AM

Dunce.
Registered Member #28 Joined: Fri Feb 03 2006, 03:29AM
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Posts: 76

An oxy acetylene torch lights it pretty easily.

Omicron

Sun Feb 19 2006, 05:38PM

Registered Member #131 Joined: Fri Feb 10 2006, 09:25PM
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I wouldnâ€™t use a oxy-acetylene touch if you paid me. The point of the magnesium ribbon fuse is to give you time to get at least 20 feet away so you if some thing goes wrong you arenâ€™t hit with a rain of molten iron.

Michael W.

Sun Feb 19 2006, 07:31PM

Registered Member #50 Joined: Thu Feb 09 2006, 04:07AM
Location: Vernon, B.C, Canada
Posts: 324

oh, you'd have a good 2 seconds to get away.....(as the molten metal hits the acetylene tank)

Marko

Sun Feb 19 2006, 07:51PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Maybe good idea for lighting it would be some powerful HV source, maybe a mot is a good idea...

But now its more dangerous also...

Mike

Sun Feb 19 2006, 08:47PM

Registered Member #58 Joined: Thu Feb 09 2006, 05:40AM
Location: Tri-Cities, Washington, US
Posts: 317

Yes arcing is actually a really good, way, just maybe have a mot or flyback a 10yards away with long wires traveling to the thermite. put the wires at jumping distance, and the arc should be hot enough to ignite it, atleast my arcs are.
:)

Omicron

Sun Feb 26 2006, 07:25PM

Registered Member #131 Joined: Fri Feb 10 2006, 09:25PM
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Just donâ€™t use copper or zinc for electrodes they will explode in to vapor.

IamSmooth

Sun Feb 26 2006, 09:22PM

Registered Member #190 Joined: Fri Feb 17 2006, 12:00AM
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I think you are all making the THermite experiment more complicated than it needs to be.
All you need is Thermite mixture, fuse, magnesium strip or (sugar/nitrate mixture).

If you set up this fancy arcing equipment it will probably get melted or splattered with molten metal from the reaction.

Swany

Mon Feb 27 2006, 12:59AM

Registered Member #261 Joined: Mon Feb 27 2006, 12:34AM
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My first interest that my parents did not approve of was, and is, chemsitry. The next vice on my list is, well, electronics. Somewhat sadly, I am a much better with chemistry than electricity...

The thermite reaction is really quite fascinating and easy. There really is no 'hard' part to it. You need an iron oxide, and you need aluminum. Some elbow grease may be required to prepare both, if they are not handily delivered to your door by a rather frightened UPS man.

Preperation of Iron oxides (II, III and magnetite): Prepare a stock solution of FeCl2. This involves dissolving an iron source in hydrochloric acid. Hydrochloric acid can be bought about 10 molar, or 31.45% at the hardware store for about 4$ per gallon. If you want FeO, or magnetite, you need to dissolve it AWAY from air, basically put it in a jar, and cover the jar such that the evolved H2 gas can escape, but no air can get in. If you want Fe2O3, go ahead and dont cover it. Now, you have dissolved all of the iron that the HCl will take. If you used steel wool, filter out the carbon now. Hopefully you have a pretty green solution of FeCl2* or and orange solution of FeCl3. Now you get to make your oxide. There are 2 ways to go about this, that are practical.
1) Add molar amounts of potassium hydroxide, sodium hydoxide, lye, NaOH, KOH, whatever you want to use. Your iron hydroxide will precipitate, filter, and dry in the oven at a few hundred degrees. This yeilds oxide.
2) Dump in some ammonia solution. This will precipirate the oxide.

Now, magnetite is a complex of FeO and Fe2O3, this means you have to prepare FeCl2 and FeCl3 solution. You can either reduce some FeCl3 solution to FeCl2, or whatever you want to do. One could oxidise their FeCl2 solution to FeCl3 with H2O2 or similar if they didnt want to let it sit in the air for a while. Now, I suggest you mix equimolar amounts of this, and add ammonia. Lots of ammonia. This will precipitate very small particle sized magnetite. This yeilds a more energetic thermite reaction...

Aluminum: Take some Al chunks, pop cans, whatever, and take an angle grinder to them. Something that spins really fast is good. Catch it all in a garbage bag. Make thermite. Or, buy it. Whatever works for you.

Other oxides can be used, in order to isolate their respective metals. Some notable and easy to obtain oxides: CuO, B2O3, MnO2. Copper oxide and aluminum behaves more like a flash powder, and can be quite violent. B2O3 thermite isnt that energetic, though you get boron powder when your done. MnO2 thermite isn't that special, though you can get MnO2 free from old batteries. A D cell battery will yeild about 70g of it!

And, why not make your own chlorates? You can make them quite easily with a homade electrolysis power supply that consists of an old computer power supply, a resistor, and some posts. To obtain sodium chlorate, electrolyse NaCl. Potassium chlorate? KCl. That is essentially it. Naturally, it is more complex, with some subtle nuances that can be annoying, but its quite easy if you really want some.
*PURE FeCl2 is actually a very light yellow. Green solutions etc. are usually due to impurities. These include chromium, and others.

Mon Feb 27 2006, 06:20AM

Registered Member #256 Joined:
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Posts: 124

thermite is coming up a lot lately in my welding class. you can get Al powder at paint stores? i think it would be worth a try
i hear using a spakler is good means of ignition btw

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