Salute (pyrotechnics)
In pyrotechnics, a salute is a device designed to make a loud "report" i.e. a bang accompanied by a bright flash of light.
All "salutes" are made with flash powder composed mainly of potassium perchlorate and dark flake aluminum powder. [1] Potassium nitrate may be used as a substitute for potassium perchlorate in the making of slow flash for small color shells two inches and under. This substitute is employed to tame the blast wave so as to not disintegrate color stars upon deflagration. Potassium Perchlorate based flash mixtures have a very fast burn rate unlike slow flash and black powder. To amateur hobbyists, the most widely used flash mixture is 70% potassium perchlorate with 30% dark flake aluminum powder. This binary mix is only one out of many formulas, some of which are considered too unsafe to mix and handle. To the novice, all flash mixtures are unsafe.
Salutes may be fired on the ground (ground salute) or launched into the air from a mortar or stick rocket. Because of the nature of flash powder, the larger 1.3 pro firework salutes are some of the more hazardous fireworks. For example, a simple M-80 will contain only three grams of flash while a three inch shell may exceed that number well over 30 times. At night from a distance, an observer will always see the flash of light before hearing the bang due to light traveling faster than the speed of sound. Salute cakes, mortars and rockets may carry titanium flakes to create a quick spark effect. These sparks always appear to be gold or silvery white. They are commonly referred to as "titanium salutes".
The aerial visual effect lasts no longer than one second but may last long enough to touch ground when the builder selects the wrong mesh, which can pose a significant fire hazard. It is a widely accepted rule of thumb in fireworks that Perc/Al based flash powders should never be used as a primary burst charge for (star shell) type fireworks of any size. A slow flash mix is always the preferred method to prevent stars from being disintegrated upon detonation. Such a mix is 50% potassium nitrate, 30% bright aluminum powder and 20% sulfur.
Any shell larger than two inches in diameter or two inches by six inches should contain only black powder as the primary burst with a small amount of flash at the very center. The flash in the center is simply a boost when used in this way. Stars bound by phenolic resin, dextrin or gum arabic all have their breaking point. Phenolic resin is the best suited and most widely used resin used.
All ground salutes over 50 mg and air salutes over 130 mg are restricted by the United States Consumer Product Safety Commission (CPSC) and the Child Protection Act of 1966.
Flash powder examples
[edit]These are two examples of flash powder that makes a very deep boom:
Blue Thunder:
- 70% Potassium Perchlorate
- 30% Blue Aluminum
- 10% Dark Flake Aluminum
- 10% Sulfur
TPA No. 1:
- 70% Potassium Perchlorate
- 15% Dark Flake Aluminum
- 15% TPA Terephthalic Acid
List of ground salutes
[edit]Cherry Bomb 1" diameter, 1/8" wall, Color: red, rose, magenta or hot pink, 1 gram of flash
Silver Salute 1/2" diameter, 1-1/2" long, 1/16" wall, color: silver, 1.5 grams of flash
M-80 5/8” diameter, 1-1/2" long, 1/16" wall, color: red, 3–5 grams of flash
M-100 3/4" diameter, 2" long, 3/32" wall, color: assorted, 10 grams of flash
M-250 3/4" diameter, 3” long, 3/32” wall, color: red, 15 grams of flash
1/4 Stick (M-1000) 1" diameter, 2.5" long, 1/8” wall, color: assorted, 25 grams of flash
1/2 Stick 1" diameter, 4" long, 1/8" wall, color: assorted, 50 grams of flash
3/4 Stick 1-1/4" diameter, 4" long, 1/8" wall, color: red or black, 75 grams of flash
Full Stick 1" diameter, 6" long, 1/8" wall, color: assorted, 100 grams of flash
M-5000 1-1/4" diameter, 6" long, 3/32" wall, color: assorted, 130 grams of flash
References
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