Jim, We are avoiding the placement of via holes under "bicycles" - two pins components. This is because the tolerances of the metal depth, the coating and the plugging or tenting causes solderability problems to the components. Regards Ofer Cohen Manager Quality Assurance, Reliability and Production Technologies Seabridge Ltd. - A Siemens Company -----Original Message----- From: Marsico, James [mailto:[log in to unmask]] Sent: Monday, November 17, 2003 22:41 To: [log in to unmask] Subject: [TN] tented over vias Hello, Technet... A quick question (or two, maybe three)... We're designing a small double-sided SMT PWB which is somewhat dense. The designer has to place plated through vias under some of the small chip components. Our only option is to tent over these vias with solder mask. My question is what's the best S.M. for this application and what's the max size hole it can be used on. Is it best to tent over both sides of the via or just one? Thanks for your help, Jim Marsico Senior Engineer Production Engineering EDO Electronics Systems Group [log in to unmask] <mailto:[log in to unmask]> 631-595-5879 --------------------------------------------------- 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 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- 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 847-509-9700 ext.5315 -----------------------------------------------------