Soldering terminology

Conventional device for smooth coverage of the lower surface of the circuit board with flux prior to wave soldering. Compressed air is directed into a tank through a foaming tube with the purpose of foaming the flux which is then spread on the rear side of the circuit board. In this method, the thickness of the flux layer can be controlled to a certain degree, but the result is usually a relatively thick coating. Furthermore, the foamed flux easily evaporates, requiring continuous supply. The covered area is sticky and therefore susceptible to contamination. Depending on the operating temperature, the composition of the solvent and its concentration must be adjusted separately. Excessively foamed flux can reach the surface of the circuit board and contaminate the components. If flux penetrates, for example, a switch element, this could lead to contact fault. Lately, the use of s pray fluxers and jet fluxers has become increasingly common.