Yes, thicker copper can be a problem. No, it's not necessarily a problem. Incomplete info in this question for my thinking. Would start looking at other factors as well. Relative hole size? Large? Soldered component in hole vs. simple via? Copper quality/grain structure? Just thick with equivalent elongation characteristics or thick_weak_large Cu grain because of too rapid copper plating? Perhaps that just intellectual stalling, tho... ;-) dw At 06:00 AM 7/24/2007, Ralph Rottnick wrote: >Lee, > >Do you also have any inromation about max Cu thickness in the PTH? In >the recent past we had some cracks and the min was ok but the max showed >values aroung .045mm. Our supplier said that the crack was caused due to >too thick copper. The crack location was on the top just below the Cu >ring. >Do you or anybody else has a suggestion how to handle or specify this? > >Regards >Ralph > >-----Original Message----- >From: TechNet [mailto:[log in to unmask]] On Behalf Of Lee parker >Sent: Friday, July 20, 2007 10:42 PM >To: [log in to unmask] >Subject: Re: [TN] Question on plated through holes general > >David > >I always advise one mil or more in the PTH. Given the non-uniformity >often seen in the PTH I would also spec the drill quality and the ratio >of the copper at the top of the hole and in the center. > >Best regards > >Lee > >J. Lee Parker, Ph.D. >JLP Consultants LLC >804 779 3389 > > >----- Original Message ----- >From: "David Harman" <[log in to unmask]> >To: <[log in to unmask]> >Sent: Friday, July 20, 2007 4:23 PM >Subject: [TN] Question on plated through holes general > > >I have a quick question and our standard that we have maybe an older >one. We currently use the ANSI/IPC-A-600 Rev E > > > > > >Page 70 Micro section: > > > >There is a table describing copper plating thickness min, requirements > > > > > > Class 1 >Class 2 Class 3 > >Average Min Thickness .020mm (0.0008in) 0.025mm >(0.001 in) 0.025 mm (0.001 in) > > > >Minimum this area .0015 mm( .0006 in) 0.020 mm >(.0008 in) 0.020mm (.0008 in) > > > > > > > >Can anyone tell me if this still is a current standards for copper >plating thickness measurements. > > > >David Harman > > > > >--------------------------------------------------- >Technet Mail List provided as a service by IPC using LISTSERV 15.0 >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 >847-615-7100 ext.2815 >----------------------------------------------------- > >--------------------------------------------------- >Technet Mail List provided as a service by IPC using LISTSERV 15.0 >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 847-615-7100 >ext.2815 >----------------------------------------------------- > >--------------------------------------------------- >Technet Mail List provided as a service by IPC using LISTSERV 15.0 >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 >847-615-7100 ext.2815 >----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 -----------------------------------------------------