I have more work to do on the check lists - maybe a lifetime's worth. The following is my current concerning via tenting with references as indicated: Blind vias (acceptable as mechanical or laser drilled holes with IPC-2315, section 4 and supplier specified aspect ratios) Buried vias ? same as above Micro vias ? same as above Vias in SMT pads (not acceptable under any condition except when filled and plated over or when micro vias used per IPC-2315, section 7.3) per IPC-7095, paragraph 6.3.1 and IPC-2315, section 7.3.2 Impact of wave soldering on top side BGA?s per IPC-7095, sections 6.4 and 6.5 Tented vias as above plus IPC-2221 and IPC-7095, paragraph 5.4.4, guidelines and supplier recommendations concerning largest hole size that can be tented without mask running down into holes. Consider hole plugging for large holes so vias may be tented. Also see IPC-7095, section 5.4 for more solder mask and tenting guidelines. Earl --------------------------------------------------------------------------------- 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 the archives of previous posts at: http://listserv.ipc.org/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 ---------------------------------------------------------------------------------