Steve makes some good points (must that good Navy training). Another thing to find out is what their cleaning process is. I have seen boards from several quick-turn prototype houses and one of the points they shortcut to save time is post-HASL or post-plating cleaning. Warning flags should be cleaning with water only. Red warning flags if using tap water. Neon glowing red warning flags if cold tap water. You get the idea. Also look at the flow rates through the cleaning process. 4-8 feet per minute good. 20 feet per minute, be alarmed. They might be optimized for these flow rates, but color me skeptical. One quick test you can do to see if they gave you a cheap solder mask. Take two boards, scrap from the same run is OK. Run one through your ionic cleanliness tester (or ion chromatography if you have it). Run the second scrap over the wave solder with no flux added and do the same test. If you see dramatically higher ionic readings in the second sample, the mask likely has absorbed residues you don't want. If you are doing engineering builds, you may be tuning your circuits around the parasitic values represented by those residues, that won't appear in good production boards. It has happened (errr, elsewhere of course). Doug Pauls Rockwell Collins --------------------------------------------------------------------------------- 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 e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest 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 ---------------------------------------------------------------------------------