Steve and Bill: I've seen this when the wrong solvent i.e. thinner/reducing agent was added to the soldermask to adjust viscosity prior to application. If you add a solvent with the wrong (lower) boiling point, when you tack dry or B-stage the mask it outgases too rapidly forming pinhole eruptions. It usually occurs when an operator is out of the correct solvent and adds whatever is "in the cabinet" to adjust the viscosity. Regards Michael Barmuta Staff Engineer Fluke Corp. Everett WA 425-446-6076 -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory Sent: Wednesday, December 06, 2006 12:44 PM To: [log in to unmask] Subject: Re: [TN] Pock marks in the soldermask?? Hi Bill! I got your pictures and put them in a *.doc file. They are here: http://stevezeva.homestead.com/files/Mask.doc They look like pin-holes to me. Here's a trouble-shooting guide for LPI's from Enthone for their mask: http://www.enthone.com/docs/Imup9.pdf Maybe one of those causes? -Steve Gregory- ________________________________ From: Brooks,Bill [mailto:[log in to unmask]] Sent: Wednesday, December 06, 2006 1:56 PM To: Steve Gregory Subject: FW: Pock marks in the soldermask?? -----Original Message----- From: Brooks,Bill Sent: Wednesday, December 06, 2006 11:54 AM To: [log in to unmask] Subject: FW: Pock marks in the soldermask?? Here are the pics Bill Brooks PCB Design Engineer, C.I.D.+ Tel: (760)597-1500 Fax: (760)597-1510 Datron World Communications, Inc. Vista, California -----Original Message----- From: Brooks,Bill Sent: Tuesday, December 05, 2006 12:37 PM To: 'TechNet E-Mail Forum' Cc: [log in to unmask] Subject: Pock marks in the soldermask?? I'm sending some pictures of what we think is an odd soldermask defect... Can someone help me identify or at least speculate on the specific cause of this strange effect? Bill Brooks PCB Design Engineer, C.I.D.+ Tel: (760)597-1500 Fax: (760)597-1510 Datron World Communications, Inc. Vista, California --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- This message (including any attachments) contains confidential and/or proprietary information intended only for the addressee. Any unauthorized disclosure, copying, distribution or reliance on the contents of this information is strictly prohibited and may constitute a violation of law. If you are not the intended recipient, please notify the sender immediately by responding to this e-mail, and delete the message from your system. If you have any questions about this e-mail please notify the sender immediately. --------------------------------------------------- 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 847-615-7100 ext.2815 -----------------------------------------------------