All, So based on the information exchanged here would it be correct to say that a reason for the less than shinny solder joint from a wave process could be too much Tin depleted from the solder pot? If so then the frequency of solder sampling may need to be reviewed to verify proper metallic mixture resulting in a cosmetically appealing solder joints? Carl >>> [log in to unmask] 12/4/2003 1:42:05 PM >>> Ed, I'm the "earlier contributor that stated" the phenomena... :) We are saying and stating the same thing in both cases but somewhere during the discussion we did missunderstand eachother... :) I appriciate the responses... :) Regards, Sasha ************************************************************************* Sasha Miladinovic - Production Engineering Amersham Biosciences, PCB Production, Umeå Tel: +46 (0) 90 150 232 Fax: +46 (0) 90 138 372 E-mail: [log in to unmask] ************************************************************************* "Ed Popielarski" <[log in to unmask]> 2003-12-04 20:12 To: "TechNet E-Mail Forum." <[log in to unmask]>, "Sasha Miladinovic" <[log in to unmask]> cc: Subject: Re: [TN] SnPb Solder pot composition Sasha, As stated by an earlier contributor, the tin rises to the top (more or less) and this is where the operators remove the dross along with solder. Just my guess, not fact. The tin drop is empirical observation over many (20+) years of being intimate with wave soldering. Always, when an analysis came back "off eutectic" tin was added. 100%, never saw one go the other way! Have a safe and happy holiday! Regards, Ed Popielarski QTA Machine 27291 Jardines Mission Viejo, Ca. 92692 Phone:949-581-6601 Fax: 949-581-2448 Cel: 949-337-2578 www.QTA.NET "Thank God for America... before it's too late!" ----- Original Message ----- From: Sasha Miladinovic To: TechNet E-Mail Forum. ; Ed Popielarski Sent: Thursday, December 04, 2003 10:17 AM Subject: Re: [TN] SnPb Solder pot composition Ed, I like Your declaration about "cold" joints... :) I had a minor war i a earlier life with a Q-department about the definition.. :) I'm not sure it any of us is right or wrong, but why would be Tin that drops? Isn't it density and temparature that is the governing factors in this case? Enyone outthere that can explain this? :) ************************************************************************* Sasha Miladinovic - Production Engineering Amersham Biosciences, PCB Production, Umeå Tel: +46 (0) 90 150 232 Fax: +46 (0) 90 138 372 E-mail: [log in to unmask] ************************************************************************* Ed Popielarski <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 2003-12-04 18:40 Please respond to "TechNet E-Mail Forum."; Please respond to Ed Popielarski To: [log in to unmask] cc: Subject: Re: [TN] SnPb Solder pot composition Yordan, Deviation from 63/37 can cause increased solder shorts in a wave soldering machine. At 63/37 (eutectic) the melt point is minimum, and there is no plasticus range. As you drift from there the melt point increases and the plastic range increases. This is why hand solder is preferred at 60/40... there IS plastic range and makes it easier to judge the joint as you solder. This is also the main cause of "frosty" joints (I hate to say "cold" since it is a very inaccurate term). Another thought to add to the mix is the accuracy of the lab. I recommend using either Alpha Metals or Kester to do the analysis (Type C which is the "whole enchilada" variety) and perhaps to rule out other variables discussed in other's postings, take a few samples, from the static part of the pot, from the wave after running at temperature, etc. If all the samples come back relatively the same, then you are good to go, but if one or two stand out, there could be something worth looking into. Additionally, (yes, another variable) the tin is usually the element that drops, not the lead. This has me wondering as well. Why? Have a safe and happy holiday! Regards, Ed Popielarski QTA Machine 27291 Jardines Mission Viejo, Ca. 92692 Phone:949-581-6601 Fax: 949-581-2448 Cel: 949-337-2578 www.QTA.NET "Thank God for America... before it's too late!" --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------