I am trying to prepare thermite in the form of solid blocks.I have found that when in powder form some of the thermite powder is blown out of the reaction vessel and onto the floor which is a real pain in the ass! :mad: I was reading this patent:
Preparing consolidated thermite compositions Patent 5,700,974

It is basically composed of ferric oxide/Al thermite (20 to 30% Al and 40 to 70% ferric oxide ) , Hydrated calcium sulphate as a binder(5 to 25%) , and a supplemental oxidizing agent(2 to 10%) which could be potassium perchlorate, potassium chlorate or ammonium perchlorate.
The oxidizing agent will lower the activation temp to around 1500-<2000 deg C and will also enhance the burning rate. I was thinking of using KClO3.
These are all mixed with water and extruding the resulting slurry mixture into a consolidated form.

I was wondering how the slurry can be extruded? My first thoughts were that the water is pressed out of the slurry. But if you are also using one of the oxidizing agents then the agent will pass through with the water because they are soluble in water.
Am I getting the wrong idea here?
Also does anyone know of any other methods or different binders?
Thanx

Calcium sulphate is also better known as "Plaster of Paris". It'll form a doughy mix that you could extrude through a cookie dough press into various shapes (rods come to mind <img border="0" title="" alt="[Wink]" src="wink.gif" /> ), or you could simply pour it into a mold of whatever shape.

If you soak the block in linseed oil and drill a hole in it, you could form a cutting torch. This is from a black book article, so your mileage may vary. :D

Thanks NBK! I already have Calcium Sulphate ready for the job. <img border="0" title="" alt="[Wink]" src="wink.gif" />
I have some KClO3 drying out that I just made and I will give it a go when it's dry.
I was also thinking of mixing it with some blu-tack binder and see if I can make some moldable thermite. :) Don't know if it will work but I think some testing is in order.

<small>[ September 28, 2002, 10:06 PM: Message edited by: mongo blongo ]</small>

Some suggestions,
Dont regard KClO3 as a general oxidiser, its too reactive chemically. Use KNO3, its much more tolerent, and better per unit mass. Your hydrated plaster of paris will be a double oxidiser, from the water of crystalisation, and from the sulphate. Sulphates are actually pretty good oxidisers for thermite mixtures. Fine aluminium and water should not be mixed, the aluminium will react and if the temperature rises enough it could set it off. This is essentially not a problem with simple thermites, but thermites with active oxidisers like chlorates, or to a much lesser extent nitrates has a risk. As ever the heat built up is a question of scale, small amounts are vastly less likley to go off. I'm not sure where your ignition temperatures come from, but they look too high, Id expect a reaction to start when the aluminium melts in mixtures with an active oxidising agent, which renders the oxide film useless and suddenly you have a very reactive metal and a molten oxidiser in the same place....