Blue Steel Fountain
From PyroGuide
Blue steel fountain, or blue steel gerb is originated from an anonymous booklet of formulas from E. D. Chemco under "BLUE STEEL FOUNTAIN", and is also mentioned on The Best of AFNIII article "Micro star Bursts-Without Micro stars."
This is an easy introductory project to ammonium perchlorate chemistry.
The AFN article suggests strontium or barium carbonates for red and green flame respectively, but this has been proven NOT to work. Only copper oxychloride seems to work, probably due to it's catalytic properties. The effect with steel (original) or ferrotitanium (variant 1) is a shower of sparkling metal above a beautiful blue flame, yet a little washed out by burning particles. With titanium (variant 2), a nice crackling effect is obtained, yet not as loud as true microstars.
Table 1: Original composition
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Table 2: Variant 1
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Table 3: Variant 2
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Method of preparation:
Please read tutorial on Fountain making, and article of stearin first. Stearin should be powdered down to -40 mesh.
In a rock tumbler ball mill with a handful of lead balls, ball mill all powdered ingredients except ammonium perchlorate and metal together for (no longer than) half hours. When done, screen the contents with ammonium perchlorate through a 40 mesh screen several times and finally diaper in metal powder(s). DO NOT screen the mix with metal powders, especially titanium.
Get a 1/2"-id by 4" parallel wound tube and first ram a 6,5mm-id clay choke to it. Use short spindle as this will be end-burning. Next, gently ram in the composition in one-gram increments, of total 10 increments. Finally gently ram a clay plug and secure it with epoxy. It is important to ram this comp gently, using protective clothing and adequate eye protection. It is also better done outside!
Light pressing with an an arbor press has proven to be useful alternative for ramming.
Drill the choke through - carefully by holding a drill-bit in your gloved hand, and insert a piece of visco dipped in NC-lacquer potassium perchlorate primer slurry. This is very important, since potassium nitrate in the visco would otherwise react with AP, forming hygroscopic ammonium nitrate.
Then find a safe spot and light it. According to some sources this fountain is said to have a nasty habit of "exploding violently". None out of ten did so, but one should still be careful. The only drawback of the gerb is a quite dense smoke it generates on a humid day, due to HCl gas in the exhaust.
Burning time of a 1/2" by 4" gerb is ca.30sec, for 10 grams of composition.