[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Dip Activation


I believe the titanium phosphate (Gernstad salt) is colliodal.  It deposits on
the parts to modifiy the subseqence zinc phosphate crystal formation. It makes
them much smaller and tighter - two important consideratons for corrosion
resistance and adhesion.  A closed loop filtering may remove it from the bath
and cause larger -and out of spec- zinc phosphate crystals.  As I recall, this
conditioner is pH sensitive, so preventing drag out from the alkaline cleaner or
back flows from the acid phosphate is important.  Sometimes a DI misting halo
will help "polish" rinse the parts - before leaving the rinse after alkaline
cleaning and just before this conditioning stage.  If the parts tend to carry
solution within them, then this is a waste of time without re-thinking the
washer configuation.  A spray rinse followed by an immersion rinse and then a
halo could help.  Counterflowing from the halo to the immersion rinse to the
spray rinse is good practice also.  Call me if you need to discuss it further
202 260 1682.