Andre, Here's my take on things. Lead Free solders do not wet as well as SnPb. So, if you use a more active flux to achieve the same level of wetting, the more residues on the hardware, which could be hardened by the higher soldering temperatures. The more residues, the more difficult it would be to clean the hardware. You may have to go to a more aggressive cleaning process than you normally would not need with SnPb. Depending upon the flux chemistry used by the solder manufacturers, you may find that the SnPb hardware is as clean as their SnPb counterparts. However, you will have to confirm this in you process development activities. For example, a few years ago, ACI checked on Lead Free soldering cleanliness. We found that except for 1 supplier (the name has been changed to protect the innocent and not to embarrass the guilty), the hardware was as clean as SnPb. With that one supplier, we found a high concentration of bromides. We discovered that the flux used was a water soluble flux, which had good wetting, but left bromide residues on the hardware. With the new flux technologies being developed, I'm sure that solder manufacturers can achieve positive wetting without leaving residues. Caveat Emptor - Let the buyer beware! For additional details call me off line. Hope this helps. Good Luck. Lee Whiteman Senior Manufacturing Engineer American Competitiveness Institute E-Mail: [log in to unmask] Ph: (610) 362-1200 x208 Fax: (610) 362-1290 This message is for informational purposes only and does not supersede, modify, or create any agreements with ACI. Information contained in this message does not bind ACI or its affiliates to any commitment, either express or implied, unless ratified in writing by an authorized representative. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Andre Leclair Sent: Wednesday, May 12, 2004 9:57 AM To: [log in to unmask] Subject: [TN] Aqueous Washes & lead free Morning all I have been noticing lately a number of Wash manufactures advertising their machines for Lead Free assembly processes. Are boards assembled using fluxes designed for the higher reflow temps (Wave or SMT) harder to remove with older washes ?? or is this an advertising gimic to try and sell new machines?? We currently have 2 older Westkleen (Triton IV & Formula 3MT) and are looking at introducing a lead free line next yr. --------------------------------------------------- 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 -----------------------------------------------------