Smoke bomb
From Wikipedia, the free encyclopedia
A smoke bomb is a firework designed to produce smoke upon ignition. While there are smoke-generating devices that are dropped from airplanes, the term "smoke bomb" is used to describe the three types of devices:
- A smoke ball is a hollow, cherry-sized sphere of brightly colored clay filled with a smoke-generating composition that produces a forceful jet of colored smoke for 10 to 15 seconds.
- A smoke candle (also called a smoke generator or smoke canister) is a cylindrical cardboard tube with a fuse, usually 1½ inches (37 mm) in diameter and several inches long and resembling a giant firecracker. Such a device creates a thick cloud of smoke for up to several minutes. Uses include providing smoke for smoke testing and creating a smoke-screen for paintball and airsoft games.
- A smoke canister (or smoke grenade) is a metal can that releases smoke when a pin is pulled. Used for signalling by military personnel.
Colored smoke devices use a formula that consists of an oxidizer (typically potassium chlorate, KClO3), a fuel (generally sugar), a moderant (such as sodium bicarbonate) to keep the reaction from getting too hot, and a powdered organic dye. The burning of this mixture evaporates the dye and forces it out of the device, where it condenses in the atmosphere to form a "smoke" of finely dispersed particles.
A simple smoke powder can be made by gently mixing saltpeter (potassium nitrate, KNO3) and sugar in roughly a ratio of 60% saltpeter to 40% sugar; add more sugar for a slower burn and more KNO3 for a faster burn. The more finely ground the saltpeter and sucrose, the better the smoke bomb. The mixture can be used as a loose powder or consolidated by adding enough water to make a thick paste, making a small lump of about a tablespoon in size, and letting it dry overnight. This is much safer than heating such a mixture, which has resulted in too many cases of accidental ignition. "Smoke Bomb gone awry", New York Times.
This formula has a variant in which the ingredients are left in powder form and the granulated sugar is replaced with powdered sugar.
More success could potentially be enjoyed when one adds another flammable substance to the mixture without "cooking" it. The best choice for this is melted paraffin. [1]
Devices or cartridges containing only the dye are used with an external heat source in a smoke machine.
In the military, smoke bombs are a means for creating smoke-screens.
Smoke bombs are often sold as consumer fireworks, but smoke grenades (with pins rather than external fuses) are not considered fireworks and are usually not sold at fireworks shops. The military-style smoke grenades also cost much more than smoke bomb fireworks. Military-style smoke grenades often cost for around $40 USD, while smoke bombs often cost a few cents.
[edit] External links
- Smoke bomb information & Guides
- A pyroguide on pyrotechics has more information on smoke bombs.
- Fireworks explained—Pyrosummit Forums
- Ultimate Colored Smoke Bomb - Step-by-step guide for fake colored smoke bombs (Note that this instruction video has been debunked and the video is almost entirely fake; potassium nitrate/sugar propellants burn far too hot, and, rather than subliming the color dyes, oxidises them altogether. The coloured effect in the video is achieved by wrapping a commercial grenade in tape and lighting it).
- Birthplace of the "Legendary Smokebomb" - Complete guide on its manufacture. (Though it has the same ingredients as another well known mixture, the ratio of ingredients and process to make it are what make it different)
