Ron, I've seen this done a couple of ways, both with LPI soldermask: 1) Give top/bottom soldermask film with the vias covered; on fab drawing say, use LPI soldermask, apply per IPC-SM-840, Class "X" 2) Give top/bottom soldermask film with the vias covered; on fab drawing say, use LPI soldermask, apply per IPC-SM-840, Class "X". And supply film layers depicting "button plugs". The fab house will apply a "button plug" over the vias prior to soldermasking. Both applications work, but you will first need to determine with your manufacturing department which is more practical and reliable. Make sure you get your fab house(s) involved in this discussion. This is becoming a common practice in manufacturing, but the wrong application can spell disaster! Good luck, Mitch Morey # Sr PCB Designer # ComStream Corp San Diego, CA 92121 Phone: (619)657-5338 Fax : (619)657-5408 EMAIL: [log in to unmask] |||||| ((o o)) ___________oOO_(_)_OOo_____________________ PCB layout is like fine art. You have to DIE to be famous! _____________________________________________ (_) (_) >>> Ron Payne <[log in to unmask]> 03/18/98 07:58am >>> We have 0.016 vias and are considering tenting vias both sides with soldermask. What is the recommended method for doing this and getting complete tenting without breaks or bulging out? We do not want dry film on the entire board. Thanks......Ron ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################