Mike You can learn alot from cross sections of the nodules. I have seen nodules formed around electroless that has "peeled" off the hole wall - this can been seen as the electroless will be plated completely around in the nodule. I also have seen nodules caused by "fluffy" electroless. It appears that the electroless is so unstable it just piles on top of itself, but does not adhere well to itself. The electrolytic then forms nodules up and around these piles of electroless. Susan Mansilla Technical Director Robisan Lab ############################################################## TechNet Mail List 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 web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################