In a word yes Current density will effect the ratio of tin/lead in ALL HBF4 based baths ,( not exclusively the McD bath ) Over time you could see a change in the metal ratio in solution, this could be minimal or nessessitate metal adds . It all depends on the average current density . The solution to work ratio effects how rapid and how large the change will be , the larger the tank in relation to panel size and through slower the change. FOr more detailed information and a good reference source try the AESF in Orlando Fl. ---------- From: Francis Lai To: [log in to unmask] Subject: [TN] Different current densities in the Macdermid tin-lead bath Date: Wednesday, March 31, 1999 8:28PM <<File Attachment: Lai.doc>>