Solder Wire

Flux cored solder wire is universally made by an extrusion process followed by drawing it through dies progressively reducing the wire diameter.

As solder is opaque and usually contains lead it is not possible to see and test inside the wire to check for flux presence.  The extrusion process is subject to variations in pressure and temperature, which can lead to occasional blockage or contractions of the flux core.  The shortest of such a flux void at the extrusion stage results in a much longer length without flux in the drawn down wire.  Solder cannot properly join metals without flux and may cause a faulty ‘dry’ joint.

Multicore Solders has employed its own unique extrusion process for over 50 years to guarantee flux continuity.  It has earned an enviable reputation for this reliability that has never been challenged.  Multicore is the only company in the world, to the best of our knowledge, that extrudes 5 truly separate cores of flux inside the solder wire.