A blowtorch uses pressurised butane, liquid natural gas or propane to provide focused heat. This heat is less intense than that produced by oxyacetylene torches or plasma cutters so it is not suitable for welding or cutting ferrous metals. However, propane torches may be used in a variety of crafts where concentrated heat is essential. Blowtorches are obviously at home in a jeweller's studio or shop, but potters, woodworkers and artists also use them.
Jewellery Design and Metalworking
Blowtorches have many uses for metal crafters, be they jewellers or swordsmiths or even model train hobbyists. Generally speaking most blowtorches cannot be used to melt metal for casting unless the flammable gases are combined with oxygen. However, blowtorches are used to anneal or soften, nonferrous metals so they can be bent, folded, twisted, drawn into wire, and forged into different shapes. Blowtorches are used to solder metal. They also may be used to colour metal by burning the surface impurities.
Woodturning and Woodworking
Blowtorches are be used to colour wood, particularly light-coloured wood such as ash. A small, pencil-sized blowtorch may be used to stipple and carmelize a small wood piece, such as a jewellery box. A larger blowtorch may be used to dramatically blacken a larger wood piece, such as a turned serving bowl. You should never do this inside your home or garage: you are using flame to colour an item that is inherently flammable. Always have water handy to quench your accidents.
Potters use blowtorches on rakuware when it is still too hot from the kiln to be touched, in order to enhance blues and greens in the glaze. Blowtorches are also used in the construction of large pottery vessels and pieces: the potter uses the blowtorch to radically speed drying of lower parts of the structure so they can support more clay, more quickly.
Pyrography is the art of burning wood, leather or paper to add detail and remove material. While specific pyrography tools are often used that do not feature an open flame, blowtorches are also used in pyrography. A blowtorch allows you to "brush" larger area of the working surface, especially wood, leather and gourds. Various blowtorches may even be used on heavy paper, especially if the paper is treated with water.