Tinning edge contacts on printed circuit boards - using automatic plant in which edge contacts are aligned horizontally after angled immersion in solder bath

摘要

In tinning edge contacts on copper laminated conductor boards in a solder bath the board, with its edge contacts at =20 degrees to the bath surface, is immersed in the bath until the edge contacts are wetted and left for a few secs. in this partly immersed position, then withdrawn at a defined speed at the same angle as the immersion angle and brought into an almost horizontal position. The edge contacts may be on the upper or the lower side of the board and the pref. device uses a motor-driven cam disk to drive a lever attached to a carrier plate on which board is clamped, so the latter is partly immersed. A fully automatic process can be employed where all the process variables are closely controlled and coating thicknesses within very close tolerances achieved.