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| Selective Wave Solder Carriers |
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These are used when single sided PCB's require to be masked from the wave. Normally if there's :- |
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.
