32 replies to this topic

[Euter]

Name of composition:Euter's blue
Composition Type: colored stars
Creator:Euter
Color/Effect:Blue
The Composition: (by weight)

Ammonium perchlorate .............70%
Copper powder ........................15%
hexamine................................15%
Shellac.................................+2-5%

Precedure/Preparation: standard, dissolve shellac in boiling ethanol. Be careful about water in ethanol
Any Precautions/Incompatabilities: This composition is incompatible with nitrates, chlorates and water.
Here are some videos of this composition
10g pumped blue star
blue mine

[vongeetch]

Very nice Euter! Did you have to use a prime with this comp? I definately like the color.-vongeetch

[Euter]

I think, this composition dont need a prime (this mine is without prime), but if you use prime it will be better. Use prime with KClO4 only.

[FrankRizzo]

Indeed! That's the nicest "cop light" blue that I've seen besides the CuBz /AP formula.

What mesh size is your copper powder?

[Euter]

I use product of reaction CuSO4 + Zn => Cu + ZnSO4
Its very fine brown powder. I dont know what mesh size is it...

[BigBang]

What size stars did you use in the mine?

Beautiful, I hope to try this as soon as I make the Cu powder. Thank you for sharing this great composition.

[Euter]

In the mine I used cut stars about 5 mm. This composition burn very fast, you can add hexamin for retadation.

[Mumbles]

Looks very nice. I've been experimenting with copper metal blues as well. I am testing one tomorrow night. On the ground it looks pretty washed out, but we shall see if it is different in the air.

[Swany]

I have been working with a composition of a very similar type that was originally mentioned by Crazy Swede at the old APC. It seems that the Cu must be quite fine, and the composition is very sensetive to moisture. Bonding with NC didn't even solve that problem for him. My copper mesh was too large, and the blue spectra is picky enough as is, though ppt.'d copper metal seems to do the trick.

Binding with shellac and EtOH also seems to keep it moisture-resistant at least for a while as well.

[Crazy Swede]

As Swany points out I have tried similar compositions before but had problems with discoloration and cracks in the unburnt stars during storage. Using shellac as a binder together with a water-free solvent (perhaps methanol or ethyl acetate would be better than ethanol?) sounds very attractive indeed!

The copper powder I used was of electrolytical grade but not as fine as one might think. I'm sure everything passed a 100 µm sieve though!

[ir-russu]

Nice blue color . ....i should test it next year....

Cu guys....

Greetings from Malta ...........

[Rogue Chemist]

I liked this comp from the moment I saw it. Unfortunatly I had to use up some of my precious perchloric acid for the prep of the ammonium perc, but even after only lighting a few g of the loose composition, it is amazing, the few grammes made a 1m blue flame.. Need some shellac for binding however.

Overall, the use of my perchloric acid was justified.

Copper was electrolytic grade(whatever that means), and at that mesh was still a very shiny powder, not like the precipitated stuff, which is even finer.

Tuesday I attempt to obtain shellac!

[Mephistos Minion]

Art stores have shellac flakes. The one in town here has 250 gramme bags of it for $13 or so.

I was looking into making Cu powder with CuSO4 and Zn, but I think I will just buy it.

[leosedf]

13$??
Too much! I got 500gr for 3 Euros

[Chemguy]

Make Cu flakes, you can buy CuSO4 1kg for 4$NZ Around $2.50 American, and zinc isn't hard to come across, I've done this and it's simple, fine and made my pyro compounds burn green.

[Mephistos Minion]

I did the calculations in my physical science class. For one kilogram of Cu I need 1030 grammes of zinc and something over 2000 grammes of CuSO4 for it. If I use granular Zn, what mesh will the precipitated Cu be? I was planning on using some Zn powder for it, to try and precipitate it very finely.

[BigBang]

Mephisto, you'll need nearly 5kg of CuSO4 to produce 1kg of Cu. This is if you don't have anhydrous and must use the pentahydrate. 1 mol of CuSO4*5H2O would be 249.62g, then to use a little excess (better this than Zn) you go up to 324.5g, or so I think.

You should get a fine percipitate no matter what size Zn you use. What will change is the time it takes for the reaction to finish.

I went ahead and tried this out. First, I made a nice solution with roughly 1L of water, and 102g of CuSO4*5H2O. I then proceded to stir in 20.5g of Zn dust. The solution turned black at this point. I let it sit for ten minutes, then gave it another good stir. I scraped my stirring device along the bottom of the reation vessle (fork in pickle jar) to bring up a brownish muck. Everything was left for about an hour to finish off. I proceded to filter out the percipitate using 3 coffee filters, saving the filtrate to make sure most of the Cu had been filtered out. When it had been, you cold see a bit still in the filtrate, though, not enough to worry over. I scraped as much off of the filter as I could, but possibly a gram remained stuck in the filter. I put the brownish red muck in the oven too dry for 2 hours. Once dry, I powdered and weighed it, finding 14g of Cu dust.

Now, I mixed everything up, using all of the Cu. My AP is 200 micron, so it could still be seen in the mix. I burt about half a gram, greeted by a pale blue flame, though the flame was rather large. I was only 5 or so feet away, which could explain the lack of the coplight color.

After this, I added 9 grams of R45-M, or about 9.5%. Yes this is freakishly high, but it really isn't too much by volume. To this, 4.5 grams of curative was added to give a very hard cure.

While still gooey, I burnt a drop of it. The blue now was deeper, and it burnt much slower than before.

Now, 12 hours later, the block that I formed it in is overall cured. I'm going to make some cut stars out of it, and hopefully test it in a mine or shell. So far it looks very promising.

[BigBang]

...and over a year later I tested the shell. The stars seemed to burn fine, but the R45-M washed out the color a bit (at least when the stars hit the ground. Old benzolift must have absorbed some moisture.)

I still like this formula. Just need to get a better feel for it I suppose.

[hst45]

I've been working with this compound too, and using the original formula with shellac binder they really need a hot prime to light. Using a good layer of Velines superprime over cut stars, followed by a dusting of meal does the trick nicely. It's a great, long lasting blue; the best that I've tried.

[psyco_1322]

When making Cu powder this way dont you have to wash off the product with straight water to get the ZnSO4 solution off? If not than your Cu powder will be tainted with ZnSO4 after drying correct?