Guenter, Very clearly stated and appreciated that way. Still, being a stubborn not very insightful and often ignorant sort, I get some of it but not all. I realize "wetting" is a function of diffusion and intermetallic formation, I think. It's the surface thing that still has me going. Werner said, as we all should understand, that surface scientists know there are a specified number of atomic layers, measured in Angstroms, composing an objects surface. If it is 1000, is this the "depth" to which diffusion takes place? Beyond this, is this fair ground as well, or does Manko's old definition still hold up? I know these questions have been answered, just as they have been asked, before many times, as we all have read and studied. It still bothers me and, I think, that is fair as soldering, solder, and the process in which metal SURFACES are joined using, I presume, a uetectic alloy will be questioned and answered many more times in the future. Simply, I want to get real comfortable, not as a surface scientist, but as a manufacturing engineering soldering guy on the floor so I can move to life without lead but, hopefully, with some other eutectic alloy used to joing "metal" surfaces. Earl --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------