Selective Wave Solder Carriers

These are used when single sided PCB’s require to be masked from the wave.

Normally if there are:

  • NPTH (Non Plated Through Holes) 3mm in diameter or greater.
  • PTH (Plated Through Holes) of any diameter that may require a post wave assembly.
  • Any area of the PCB that solder would adhere to if exposed to the wave e.g. groundplanes.                               

Selective wave solder fixtures should be considered whenever you are having to use kapton tape to mask features. Savings can be made in both materials and manpower.

Masking Thickness

Particular design attention is required to select the correct masking thickness as two effects
dominate the behavior of the masking:

  • Thermal bowing due to the temperature difference across the web thickness.
  • Thermal buckling caused by the bulk rise in temperature of the masking over the parent carrier.     

Our Research and Development has yielded design rules which allow us to quickly determine the required thickness.