TXpyro Posted March 7 Share Posted March 7 Hey, I'm thinking about making some copper thermite to put in my fountains. Would this be a good idea? Should I use a 3/1 ratio or a 2/1? I'm just hoping it will give a cool effect. I haven't gotten the stuff to do it yet. Link to comment Share on other sites More sharing options...
CHNO Posted March 7 Share Posted March 7 (edited) 3 CuO: 68.1% 2 Fe: 31.9% + 10% NC-lacquer OK: 81.6% CuO + 18.4% Al 76.6% CuO + 23.4% Mg 54.9% CuO + 45.1% Zn Better? Edited March 7 by CHNO Link to comment Share on other sites More sharing options...
Crazy Swede Posted March 7 Share Posted March 7 3 hours ago, CHNO said: 3 CuO: 68.1% 2 Fe: 31.9% + 10% NC-lacquer Really? What kind of effect is produced? I never thought about that combination since iron is not really considered as a reactive metal, in the thermite context, and it is not mentioned in the classic reference "A Survey of Combustible Metals, Thermites and Intermetallics for Pyrotechnic Applications" by Fischer and Grubelich (can easily be found as a pdf!). Usually, copper thermites refer to combinations of copper oxide with aluminium powder where the particle size of the aluminium strongly affects reactivity. Pigment grade Al or dark Al produces extremely energetic reactions, essentially a flash powder is created that is way more sensitive than ordinary Al/Fe3O4 thermite, so be careful when handling that @TXpyro and it might be difficult to produce a fountain from it! Also, classic copper thermites only produces a dull flash and brown smoke so it is not a really visually pleasing effect! Link to comment Share on other sites More sharing options...
Zumber Posted March 7 Share Posted March 7 1 hour ago, Crazy Swede said: Really? What kind of effect is produced? I never thought about that combination since iron is not really considered as a reactive metal, in the thermite context, and it is not mentioned in the classic reference "A Survey of Combustible Metals, Thermites and Intermetallics for Pyrotechnic Applications" by Fischer and Grubelich (can easily be found as a pdf!). Usually, copper thermites refer to combinations of copper oxide with aluminium powder where the particle size of the aluminium strongly affects reactivity. Pigment grade Al or dark Al produces extremely energetic reactions, essentially a flash powder is created that is way more sensitive than ordinary Al/Fe3O4 thermite, so be careful when handling that @TXpyro and it might be difficult to produce a fountain from it! Also, classic copper thermites only produces a dull flash and brown smoke so it is not a really visually pleasing effect! And thermite in a fountain looks odd to me......It would produce molten metal all over. Link to comment Share on other sites More sharing options...
TXpyro Posted March 7 Author Share Posted March 7 (edited) I was thinking I could make some sparklers with it. If I was to make a fountain with it, could I just ram it like a black powder fountain? Edited March 7 by TXpyro Link to comment Share on other sites More sharing options...
Zumber Posted March 7 Share Posted March 7 Beware thermite is extremely high temperature reaction. No any parts of body should come in its vicinity while burning it. Link to comment Share on other sites More sharing options...
CHNO Posted March 7 Share Posted March 7 Are Crackle-Stars no Thermite? Link to comment Share on other sites More sharing options...
Crazy Swede Posted March 7 Share Posted March 7 Thermate (kind of thermite + barium nitrate) fountains exists in the form of metal cutting lances. One example is the Fire Ant that is/was used to disarm land mines. A nozzle that can handle the extreme temperature is needed! If a fountain was made with course Al, to slow down the reaction, together with CuO, you would probably only see reddish sparks from the burning copper metal. A bluish flame might be possible if you mixed in some PVC but it would probably make the composition very hard to ignite. @CHNO, thermitic reactions are probably a part of the crackling phenomena but I would guess they are more complex. How come you ask? Link to comment Share on other sites More sharing options...
Richtee Posted March 7 Share Posted March 7 And I’ll tell you...I messed with a black Cu oxide thermite, that turned out to be flash. BOOM. High vel copper molten BB’s everywhere. Use EXTREME caution. Link to comment Share on other sites More sharing options...
TXpyro Posted March 8 Author Share Posted March 8 4 hours ago, Richtee said: And I’ll tell you...I messed with a black Cu oxide thermite, that turned out to be flash. BOOM. High vel copper molten BB’s everywhere. Use EXTREME caution. Caution? Is safety really a concern? From what I've heard copper thermite is relatively insensitive. And the whole molten metal BB thing sounds made up. I'm just tryna have some fun. So how about copper thermite sparklers? Do you think those would look cool? 1 Link to comment Share on other sites More sharing options...
Richtee Posted March 8 Share Posted March 8 No Link to comment Share on other sites More sharing options...
Richtee Posted March 8 Share Posted March 8 But by all means I won’t tread on you, Texas. Nor have to sweep you up. 1 Link to comment Share on other sites More sharing options...
ThrownBiscuit Posted March 8 Share Posted March 8 Safety is a concern with copper thermites, .22LR reactive targets are made from copper thermites. Now if you were referring to like CAD-weld copper thermites they use a few more additives to slow burn rate and also higher particle sizes. Cad-weld does not look particularly appealing for use in fountains. As Crazy Swede stated copper thermites produce brown smoke and not a lot of sparks. Link to comment Share on other sites More sharing options...
TXpyro Posted March 9 Author Share Posted March 9 Why does everyone say copper thermite is so dangerous? I don't understand. Please explain... Link to comment Share on other sites More sharing options...
Richtee Posted March 9 Share Posted March 9 As I said... a percent or two one way or another and it is flash. With the binder- perhaps not, but PROCEED WITH CAUTION. Link to comment Share on other sites More sharing options...
Arthur Posted March 9 Share Posted March 9 Just occasionally a copper thermite reaction goes much faster than intended and rather than burning it reacts too fast and approaches a detonation rate of reaction likely spraying molten metal over it's surroundings, which ceases to be entertainment. 2 Link to comment Share on other sites More sharing options...
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