In respone to inquiry as to whether multilple HASL dips to inprove coverage
of lands.

Whenever the board undergoes HASL, the copper thickness decreases by 0.00007
to 0.0003 inch per dip.  The quicker the dip the small the amount of copper
goiing into solution.  As many of you have seen,  there may be complete a
copper washout, hole voiding and barrel cracking after 3 dips, and for some
HASLers after 2 dips.  A look at the microsection after multilple solder dips
is a necessity and should be part of any process control system that allows
multiple-HASL's.

Phil Hinton 
Hinton PWB Eng