Dear Francis , There are few possibilities which could hlep you narrow down the problem :- 1.Check your palladium bath concentration . 2.Check the electroless copper bath air agitation 3.Check the electroless copper bath auto dosing of formaldehye , caustic and copper rate .Do set up a calibration on a weekly basis the dosing rate and also a daily weight gain control .With the irregular dosage of formaldhedye and high air agitation , chances of this happening is high .However , do not overlook at the digital copper level indicator as it may also sometimes be faulty .(If you have a unit) Hope the above could assist you in your troubleshooting . HH >Have you checked the plating rate , it sounds as if the electroless copper >bath is over active causing nodular copper growth >I am assuming you are using high build, which Macdermid electroless is it ? >(I am ex Macdermid Technical Sales in UK) > >----- Original Message ----- >From: Francis Lai <[log in to unmask]> >To: <[log in to unmask]> >Sent: 05 June 1999 01:56 >Subject: [TN] PTH Problem > > >> We use the Macdermid PTH line. Recently, after PTH there are fluffy, >> small minute copper deposits around the drilled holes besides the >> electroless copper on the PTH walls. The copper surface of the panel >> looked porous. After copper plating, they became pits on the surface of >> the panel and nodules on the PTH walls. >> Can any one help? >> My e-mail : [log in to unmask] >> THANKS!!!!!!! >> >> Francis >> >> ################################################################ >> TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c >> ################################################################ >> To subscribe/unsubscribe, send a message to [log in to unmask] with >following text in the body: >> To subscribe: SUBSCRIBE TechNet <your full name> >> To unsubscribe: SIGNOFF TechNet >> ################################################################ >> Please visit IPC's web site (http://www.ipc.org) "On-Line Services" >section for additional information. >> For technical support contact Hugo Scaramuzza at [log in to unmask] or >847-509-9700 ext.312 >> ################################################################ >> > >################################################################ >TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c >################################################################ >To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: >To subscribe: SUBSCRIBE TechNet <your full name> >To unsubscribe: SIGNOFF TechNet >################################################################ >Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. >For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 >################################################################ > > > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################