Hi We always treated plugged vias as a separate process and supplied and artwork just for that otherwise we just got vias covered with soldermask. If its to have a better suction on automatic testing equipment soldermask will do fine other than that you are probably better with a separate process and specify what kind of epoxy you want to use. Stephan Renaud Sr. Product Designer -----Original Message----- From: Jack C. Olson [mailto:[log in to unmask]] Sent: Thursday, December 13, 2001 9:29 AM To: [log in to unmask] Subject: [DC] Plugged Vias I need a quick verification here, hope someone can help... I have always been under the impression that when a drawing specifies "plugged vias", it means the holes are filled (or at least partially filled) with an epoxy, the epoxy is cured, and then the vias tented with solder- mask. In the batch of boards we just recieved, I'm pretty sure they just used the LPI soldermask to fill the holes, and the fabrication vendor says "well, soldermask is epoxy, so what's the difference". I'm not sure LPI glopped into the holes is cured properly, and in my application the board is maintaining a pressure seal, no air is supposed to escape "through" the board, which is why I asked them to plug the holes in the first place. Can anyone enlighten me on this point? Is soldermask the same epoxy as the epoxy used to fill holes? Or has it always just been soldermask in the holes and I just didn't know it? thanks in advance, Jack p.s. If plugging really is a separate step, would it help to supply a separate artwor that just has vias exposed so they know what to plug? just curious, not a-retentive : ) ---------------------------------------------------------------------------- ----- DesignerCouncil 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 DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------- ----- --------------------------------------------------------------------------------- DesignerCouncil 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 DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------