The method I'm about to describe is the least dangerous way I know of to work with a flash report composition. Additionally, it is becoming accepted wisdom that unless one has a Federal High Explosives Manufacturing license
, the manufacture of flash reports is a no-no.
The black powder, whistle fuel, or strobe fuel reports described above will produce nice report headings. Many folks will be unable to procure the chemicals necessary to produce the flash-report compositions I'm about to describe, and even if you have these chemicals on hand, I'd strongly recommend waiting to work with them until you have a lot of fireworking experience under your belt, and a Federal license.
This flash-report method is called the "binary method" of mixing the composition. That is because the components are added to the report casing individually, and are not mixed until the casing is closed and sealed. This is the way theatrical flash powder is mixed when it is used professionally. This method isolates the flash powder from static electricity, friction, and stray sparks-frequent causes of accidental flash explosions.
Binary-mixing flash composition completely eliminates the need for the open mixing of flash, as well as handling and storing loose flash powder. This eliminates many of the dangers of using flash powder.
Since the flash powder is actually mixed in the report casing after it is glued shut, enough extra room must be left in the casing to allow this mixing to be done. For this reason, I only fill the casing about 2/3 full with the components of the report composition.
Through trial and error, by marking one-third and two-thirds marks on the inside of the plastic casing, and introducing increments of the composition ingredients a little at a time, I determined the recommended amounts below to add to these plastic cans.
First of all, I sifted some potassium perchlorate
and some dark aluminum
onto their own individual, clean paper plates. I used a fine mesh kitchen colander to do this, and cleaned the colander between chemicals to avoid cross contamination.
Potassium Perchlorate and Dark Aluminum Sifted onto Paper Plates
Then I assembled my perchlorate, aluminum, titanium, and some bran flakes on my workbench. Bran flakes aerate the flash ingredients once the casing is closed, and prevent the powder from settling and packing down too tightly.
Flash Report Composition Components Ready to Be Weighed
I filled the shell casing in two stages using dedicated scoops. I weighed the components individually, and placed them into a plastic casing in layers. First, I introduced 14 grams of the perchlorate into the casing, then 6 grams of the aluminum, then 1 gram of the bran flakes (slightly rounded teaspoonful), and finally 7 grams of the titanium. These components were never mixed together in the open. This filled the casing one third full.
In the second stage, I did the same thing again, which filled the casing to the two-thirds full line. That was as full as I wanted the casing, since I wanted to leave it one-third empty for easy mixing once the casing was closed.
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