Torch

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These hand-held items are used for display purposes during parades, for signaling in the rail traffic and for various other applications. They are quite closely related to portfires and bengals and have been discredited because they are often liable to cause accidents in crowds e.g. during football matches. Nowadays non-pyrotechnic torches made of sackcloth dipped in paraffin wax are frequently used. By contrast, pyrotechnic torches generally are relatively expensive and make use of larger amounts of coloured compositions. This may be a difference to portfires, where reliable burning is the main requirement and the beauty of the effect is of secondary importance only.

However, pyrotechnic torches usually are 18-24mm in diameter and something between 20 and 50cm long. The case is normally a wet rolled tube consisting of about five turns of a thin kraft paper. The compositions generally are quite drossy and produce a lot of smoke. They often employ woodmeal, starch or wheatflour to extend the burning time and to cheapen the units. Lance compositions can be used for torches adding 5-10% of woodmeal. This addition is a also possible in case of the following compositions.


Table : Compositions for pyrotechnic torches:

Lancaster A Lancaster B Lancaster C
Potassium perchlorate 52 25
Strontium nitrate 45
Aluminium (bright, 150 mesh) 24
Aluminium (Flitter, 30-80 mesh) 20
Aluminium (dark pyro) 18
Dextrin 4
Barium nitrate 76
Sulphur 4
Petroleum jelly 2
Shellac (30-200 mesh) 14
PVC 6
Linseed oil 1
Magnesium (40-120 mesh) 9


The units are fitted with a wooden handle and one end is primed with gunpowder or a slurry made of potassium chlorate and charcoal airfloat (with add. dextrin). In the latter case the units also feature an enclosed wooden striker unit pasted with a slurry of red phosphorus. This ensures ignition when grated against the chlorate surface (inverted principle of a safety match). For more detailed information on torches the reader is referred to Weingart´s "Pyrotechnics".


Sources: Lancaster, Ronald: Fireworks, Principles and Practice, p. 227f

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