Introduction: Thermite

About: Working wireless-ly.


Quick explanation of thermite:

A mixture of iron oxide Fe2O3 (rust) and aluminum powder. When it is ignited the aluminum powder reacts with the O3 part of the rust in a highly exothermic reaction, the resulting product is molten iron.

Thermite is commonly used in welding, because the molten iron has the ability to seep into cracks in metal. It cal also be used to melt through things as shown in an episode of Brainiac and the movie The Sixth Day.

I have made thermite a few times, but never in large enough batches to burn through anything significant. Aluminum powder is hard to come by and I never had a good enough reason to use what little powder I had.

Step 1: Materials

All materials can be found here or on E-bay. You can either buy and mix the chemicals yourself or buy premade thermite from unitednuclear.

1. Iron oxide
2. Aluminum powder
3. Magnesium ribbon or thermite ignition mixture

For a more exotic mix you may also want to buy:

4. Barium Nitrate
5. Sulfur
6. Dextrin

Step 2: Mix

Mix 76.3% iron oxide with 27.3% aluminum powder to make thermite.

To make the military version Thermate create a mixture of 68.7% thermite, 29.0% barium nitrate, sulfur 2.0%, and dextrin 0.3%.

Step 3: Ignition

The safest container to hold the thermite while igniting it is a terracotta or ceramic plant pot with a hole in the bottom. Place a tissue or coffee filter on the bottom of the pot to prevent the thermite from spilling through. Put the thermite in the pot, and then when it ignites it will burn through the paper spilling molten iron onto whatever is underneath.

Thermite requires extremely high temperatures to ignite (about 4000 F). Ignition can be achieved in multiple ways.

Magnesium ribbon, although unreliable, is still the most popular way to ignite thermite.


Thermite ignition formula sold on unitednuclear

A mixture of Potassium permanganate and glycerine will undergo a reaction that can provide enough heat to ignite thermite.

Allow yourself at least 10 seconds to get the hell away from this stuff, especially if you made Thermate.

Step 4: Safety

Thermite burns very hot. It is virtually impossible to extinguish. Do not pour water on it because it will not extinguish it and it give you steam burns in the process. If you are having this burn through something put a bucket of sand underneath it.

Only do this outdoors in a completely nonflammable environment.



  • Woodworking Contest

    Woodworking Contest
  • Casting Contest

    Casting Contest
  • Make it Move Contest

    Make it Move Contest

We have a be nice policy.
Please be positive and constructive.




Reading about all these different mixtures, can any of them be made in a weak enough mixture to 'paint' on wood in a simple design that would burn or etch the wood just where it is painted on.

1 reply

Use a soldering iron at a low setting, this will allow for greater precision as well.

al foil and rust will produce the same product

Is the thermate by weight because the ratio does not equal 100 percent either.

Whats the ratio with copper oxide?

Can you give any info on your stump burning experience? Just received the ingredients (pro grade rusty and aluminum powders), and have 26 acres of nasty stumps... Any info is appreciated!

It works well with getting the stumps burning. The more product that you use,the faster the stump is consumed. Dry pine stumps burn the best. It will not make the stump disappear instantly but it is faster than charcoal and more fun than digging! What ever you do, PLEASE do it safely. Thermite is hot!

sorry to be a smart arse, but the percentages of the mix add up to more than 100%. if you mix 76.3% iron oxide with 27.3% aluminum powder, then you get 103.6% thermite. this doesnt make sense to me, so could you explain it a little please. thanks

9 replies

Were you directed here by one of mythbusters episodes with thermite? I was!

Cowboy does this really work

believe it or not, no. Ive never watched mythbusters

I love the ice thing! Ive seen almost every episode! Wensdays at 9!

In Eastern stations it used to be, but now its at 8 for some reason. I hear the next myth is on Golf Balls and if the dimples affect flight. it was in a Pop Mech article about the Mythbusters.

he just wants to get fancy-ish woth that. mix 75 and 25. also, you can do aluminium powder grinding or blending aluminium paper!