LOL, agreed, but I would prefer to be holding the test data. Common sense is still required. I have yet to see any issues with solder paste whose shelf life was extended 3 months so as to use it up. Trying to justify use of a three-year-old wire solder, well, that's a little different. -----Original Message----- From: Whittaker, Dewey (EHCOE) [mailto:[log in to unmask]] Sent: Friday, June 05, 2009 1:04 PM To: TechNet E-Mail Forum; Stadem, Richard D. Subject: RE: [TN] Flux cored wire solder shelf life While I can't dispute the merit of your logic or argument, when the proverbial caca hits the rotary device I'd much rather be holding an umbrella than a light saber. Dewey -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D. Sent: Friday, June 05, 2009 10:29 AM To: [log in to unmask] Subject: Re: [TN] Flux cored wire solder shelf life I respectfully disagree. Within J-STD-004, -005, and -006 are specific instructions for requalification of solder paste, flux-cored wire solder, and fluxes. An example is J-STD-005 par. 6.2 and 6.3, and Table 4, where it states "If the stated shelf life on a product is expired, but it meets the performance test, it may be used. If the material is requalified, the new shelf life shall be considered to be half the stated shelf life." This section goes on to provide recommended shelf life extension inspections (testing methods). For solder paste, all that is required is a visual inspection and a viscosity check. As a consultant, I have saved a few companies several thousand dollars in material scrap avoidance by simply documenting the tests to be used for requalification within their own building. These tests are defined in IPC-TM-650, along with Test Report forms, such as Table 1 within TM 2.4.34.1, which has specific Inspection Purposes listed on the top of the page, of which one is "Shelf-life extension". However, for solder paste I do include a requirement to test the agglomeration and wetting per the TMs. I don't feel that a visual check and viscosity measurement alone are sufficient. My re-qualification procedures include re-labeling and re-stocking instructions for priority use. Nowadays, ten 500 gram cartridges of solder paste costs between $850-$1000. It takes about 2 hours to requalify a sample if they are all the same lot code. It saves the company money, allows the use of perfectly good material, and keeps a lot of waste out of the environment. Yes, I know this should not be necessary if the company controlled its purchases so nothing ever expires. That is sometimes difficult to do however, and all of the big solder paste, wire solder, and flux vendors specify minimum lot buys that are sometimes more than a small to medium size manufacturer can use up before they expire. It's called planned obsolescence, and it can be very expensive. This is why these methods for re-qual were developed. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Whittaker, Dewey (EHCOE) Sent: Friday, June 05, 2009 11:29 AM To: [log in to unmask] Subject: Re: [TN] Flux cored wire solder shelf life If the solder was good initially and stored anywhere, except near Doug's Mountain Dew stash, it will be good for years. The problem is the cost of having an acceptable process for extending shelf life. In the long run it is probably more cost effective to discard all materials that have passed/exceeded their expiration/shelf life dates, then to acknowledge the non-conformance, segregate, inspect, disposition the non-conformance ( establish accept/reject criteria, re-test, re-certify, re-label) and eventually either discard or return the materials to stock. Dewey -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory Sent: Friday, June 05, 2009 8:38 AM To: [log in to unmask] Subject: [TN] Flux cored wire solder shelf life Well, we made it to Friday! I'm going ask ya'll a couple of question that I think I know the answer to, but I want to hear what you think. Right now I'm in the midst of gathering up all my solder dross, expired solder paste, and wire solder for a shipment to my recyclers. I noticed we had a bunch of wire solder in the locker of our training room that was really old, like it was manufactured back in February of 1997. The alloy is 63/37, the flux core is a pretty active water soluble organic acid. The manufacturer says that shelf life for flux cored wire solder is 3-years. But when I took some of the solder and soldered with it, it soldered absolutely fine. Wet and flowed out with no problems whatsoever. So my question is, have any of actually had any problems soldering with flux cored wire solder because it was too old? Do you think that manufacturers shelf life is realistic? Steve --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 -----------------------------------------------------