Yvon, .010"-.012" over drill size is pushing the limit. .018" via (finished hole size, plated, I am assuming) would probably be drilled with a .024" drill bit, assuming a +/- .003" tolerance on finished hole size. .034" would then be the pad size. The PWB supplier would definitley let you know if that was a problem. That is why it is a good idea to involve suppliers in DFM reviews. JU -----Original Message----- From: Yvon Hache [mailto:[log in to unmask]] Sent: Wednesday, February 02, 2000 8:06 AM To: [log in to unmask] Subject: [TN] VIA pads Good morning everyones around the World, I have a design/manufacturing question. If we use a 0,018" VIA, what is the smallest pad size we can use on this VIA without causing problem in PCB manufacturing? thanks Yvon Hache, P.Eng. Tel: 506-863-2467 Email: [log in to unmask] Concept + Inc. Scientific Park, Suite 100 55 Crowley Farm Rd, Moncton, NB E1A 7R1 Tel: 506-858-4153 Fax: 506-858-4075 Web: www.concept-plus.com ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ############################################################## ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################