Water torch

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A water torch, sometimes called a water welder, is a device that produces a high-temperature directed flame. Water torches are used for the precision welding, brazing, and cutting of metals typically employed in the making of jewellery,electronics boards and parts, and fiber optic applications.

[edit] Operation

A water torch operates by passing an electric current through water (water electrolysis) to separate water into hydrogen and oxygen. Potassium hydroxide or another safer substance is added to the water as an electrolyte to make the water more conductive, thus increasing the current which can be passed through it, and the rate of gas generation. The gases are reunited at the torch head and ignited. An alcohol bubbler, which mixes a small concentration of vaporized alcohol with the hydrogen and oxygen, is added to some models. Others use the flux and water mixture to produce the gas that is then dried through a cotton or similar synthetic fiber blanket inside the unit to deliver the ignitable gas at the torch tip.

[edit] Uses

Water torch systems are typically limited to jewellery and electronics applications. The heat output of the systems reach slightly above the melting point of fine gold, enough to solder small platinum findings in jewellery applications. In making jewellery, the water torch is particularly suited to the small shop and hobbyist jeweller due to its exceedingly safe operation compared to the oxy-fuel setups often used by jewellers.

The tips that are supplied with products such as the hydro-flux welder (US based Okai corp.) are precision oriented. The tips match the gauge of mill products on the B&S scale. They can be combined up to but not to exceed 10 gauge by using two torches with, for example, an 18 and a 20 gauge tip, to achieve higher temperatures or larger area coverage. These make for soldering and brazing operations more suited to jewellery fabrication. To use two 22 gauge tips would be an unacceptably unsafe operating procedure. Even the use of two 20 gauge tips would be precarious. The major drawback in using the supplied small tips and the water torch in general in jewelery making is that the air pressure that the torches generate tend to blow the solder-ready workpieces out of alignment quite easily. Use of a fixturing compound is often required to hold small metal pieces, or findings in place during soldering operations. It is more efficient then securing parts with stainless steel or iron binding wire.

Additionally, they are used in forming preform blanks via chemical vapor deposition in the manufacture of fiber optics. Hydrogen oxygen torches are also used in the ceramics and sensor industry, where the temperature or reactivity of the flame is required.