Here's a photo of some raised vias at another company that I had experienced in the past; http://stevezeva.homestead.com/files/Raised_Vias.jpg We almost rejected the boards, but the project was so hot we thought that we would try one and see what we wound up with. Surprisingly, they went together okay. The customer accepted the boards knowing what the bare boards looked like. It was just lucky that the raised vias were within the solder paste footprint. The PCB fabricator got a butt chewing and was told that they needed to do a better job of planarizing them, and to never send us boards that looked like that again. They got the message... Steve -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D. Sent: Monday, October 31, 2011 9:50 AM To: [log in to unmask] Subject: Re: [TN] maximum height of artifacts above the soldermask Amol, you are correct, I have run into the same issue. Our board fabricator took steps to correct this issue after it was discovered, and our paste printing issues disappeared. It can be done. dean -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Amol Kane Sent: Friday, October 28, 2011 7:45 AM To: [log in to unmask] Subject: [TN] maximum height of artifacts above the soldermask Dear Technetters, Is there a spec/guidance/industry best practice recommendation on the maximum height of artifacts (like silkscreen, via tents etc.,) above the soldermask surface?. Assuming the stencil foil sits squarely on the soldermask, any height above that will induce a (localized) standoff if any such artifact is near the pad. We have some boards in which the via tents are 7 mils above the rest of the mask surface. Some of these vias are close to fine pitch devices. I am afraid that I won't be able to control the volume of paste during printing leading to shorts. The board house saying I won't have an issue (big surprise there! :)). Is there something I can use as a basis of my push back ? Thanks in advance!! Amol Kane | Process Engineer Catalyst Manufacturing Services, Inc. 941 Route 38, Owego NY 13827 Phone: (607) 687-7669 Extn 349 | Website: www.catalystems.com<http://www.catalystems.com/> ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. 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