Hi Chester, I've had to remove mask from SMT pads before, and the only way I could find to do it was with the very careful use of an exacto knife and dremel tool. I remember people saying that Lasers are effective. PTH pads are another story I think that would be pretty tricky with an exacto knife. Do know if any mask got down inside the holes? Steve -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Harner, Chester Sent: Monday, February 22, 2010 2:14 PM To: [log in to unmask] Subject: [TN] Removal of Solder Mask from CU pads IPC7711 provides methods for removal of "Conformal Coating" and epoxy coating is included in the discussion. However, could it apply to the removal of epoxy solder mask? I have some boards that made it into pick and place with a few SMT pads covered with solder mask, and four through hole components with no solder mask openings around the pads. It wasn't discovered till the SMT parts (0603 caps) fell off the assembly and the through hole diodes would not solder. The Question - Is there a way to remove the solder mask from the pads and still meet IPC-600/610 requirements. Chet Harner Sr. Engineer Crane Hydro-AirePO Box 7722 Burbank Ca - 91510 818-526-2600 x3557 ---------------------------------------------------------------------------- ---- We value your opinion! How may we serve you better? Please click the survey link to tell us how we are doing: http://www.craneae.com/ContactUs/VoiceofCustomer.aspx Your feedback is of the utmost importance to us. Thank you for your time. ---------------------------------------------------------------------------- ---- Crane Aerospace & Electronics Confidentiality Statement: The information contained in this email message may be privileged and is confidential information intended only for the use of the recipient, or any employee or agent responsible to deliver it to the intended recipient. Any unauthorized use, distribution or copying of this information is strictly prohibited and may be unlawful. If you have received this communication in error, please notify the sender immediately and destroy the original message and all attachments from your electronic files. ---------------------------------------------------------------------------- ---- ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- 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 ----------------------------------------------------- ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- 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 -----------------------------------------------------