Copper powder - Fountains?

[mike_au]

My black powder so far has been a little bit too slow for rockets or anything fancy so I thought I would try making some fountains.

 

I made one last weekend that went fairly well, I mixed in iron flakes and a little bit of aluminium powder and got red and white sparks.

 

I have found a place near by that sells copper powder but I haven't found much info about it. I have found one or two references on the web saying that it is no longer used because other chemicals are better, and a couple more explaining how to make stars with it. The star mixtures also include a chlorine donor.

 

Since I don't have any of the "better" chemicals, is there any reason why I can't use copper powder in a fountain? Will it need a chlorine donor (my understanding of the metal in fountains was that it burned just like if you stuck a chunk of metal in a fire, and plain old copper makes a green flame in fire)?

[nick2354]

My black powder so far has been a little bit too slow for rockets

You could try a core burning rocket. The fuel you use, can NEVER be to slow for use in core burners.

 

I use this recipe. Its complete garbage, but it still reaches about 150 metres.

60: KNO3

30: Newspaper charcoal

18.5: Assorted hardwoods (20 mesh)

10: Sulfur

 

I doubt that the BP you are using can be worse than that.

 

 

 

Since no one has posted anything on the copper, I will post.

 

Try it. You have nothing to lose besides some copper powder. Now to your question on whether to use a chlorine donor, I have no clue.

Maybe someone with some experience can answer that one?

[mike_au]

I've found the problem with my powder, I was mixing by hand.

 

Now I have a ball mill it is 1000x better. I've made up another end burner but haven't tested it yet, I suspect it will work this time.

 

I tried another fountain on the weekend with a higher % of coarser Al and it worked far better than my first one. I've got some copper pipe that I might try to file down and try out this w/end.

 

I'll post again with the results.

[Gunzway]

I am not too sure about cooper powder sorry. I guess you could do something with it but it would not be as cheap and as good as other greens. I just use Al and Iron in my fountains. Living in Australia does not give you a wide selection of colours. Hopefully I can make Potassium Perchlorate soon which will be great.

[mike_au]

If you don't mind me asking, where do you get your Al?

 

I bought some from a fibreglass shop but I think it is too fine.

 

There is a company over east that sells metal powders in various meshes over the internet, so I might get some off them when I have some more cash to waste.

 

Do you have a better source?

[Gunzway]

http://aldaxstore.com.au/c/145843/1/metal-powders.html

That is one website which I know of and they are located in Australia. Yes, they are a good supplier. I actually used angle grinder and sometimes just hand file aluminum, yes a very laborious task but I didn't need much.

 

Personally I have not ordered from that website yet... But I plan too. I say it's a good source because one of my friends in NSW which I talk to regularly ordered there and he said it was good. So I am going off his word. I just say order from there.

 

Mind sharing your source?

[MilkyJoe]

I bought some from a fibreglass shop but I think it is too fine.

 

too fine, hah! most people have trouble finding fine powder.

 

I know a few people who use aldax aluminum and they have said that it is good for glitter stars and fountains.

 

I usually just use a coffee grinder to grind my al. NEVER use that same grinder to grind oxidizers!

[rocket]

I got some aldax Al, its good stuff. Worked well in every thing I've tried it in so far. Its 300mesh atomized btw

[Mumbles]

Yes, you absolutely need to ball mill the powder for end burners. Core burners, not so much though. Most people just hand screen for core burners.

 

The copper powder I have a feeling will be disappointing if you are expecting green and blue sparks.

[Sylar]

I haven't tried it, but I think Cu powder is too unreactive to use in fountains.

 

The colors of a fountain are defined by combustion of the particles in the air, not by the composition. Only where you have enough heat to vaporise the copper it will color your flame a bit.

 

Look up the boiling point of copper metal. Fat chance of reaching that in a typical fountain composition.

Burning metal compositions can reach that temperature no problem, but by adding Mg or Al you probably won't even notice the blue ...

 

In case you are willing to try (but probably fail): You'll need a very hot composition, at least 10-15% fine Al powder, not too much energy gobblers (chlorine donors, binders, ...) and a very oxidising atmosphere around the vaporised copper, so more then normal of nitrate/chlorate/perchlorate. I would add no more then 10% copper. Given the high density of copper, that won't be much volume ...

 

 

EDIT: be prepared for some noise if you come too close to flash compositions!! Don't stand near, wear eye an ear protection and keep the tests small!!!

[mike_au]

Gunzway: My supplier for Al isn't nation wide or anything, its a little place called "Fibreglass supplies" or something to that effect. They have Al in two sized, one is so fine it seems to be a liquid and the other is about the same as alfoil put through a cheese grater. They can order in other metals (copper, brass, iron) in similar sizes.

 

This is all starting to sound complicated, inefficient and possibly a little dangerous.

 

Thanks to everyone who has replied, but I might stick with trying to improve my whites and golds until I can get some of the "better" colouring chemicals.