Carl, My interpretation of the 50% vertical and 360 deg. circumference primary and secondary side barrel fill applies only to class 2 only when ground and conductor planes act as heat sinks. I believe this because less than 75% fill is noted as a defect for both class 2 & 3 on page 6-6 and then on page 6-7 class 2 is noted as acceptable for thermal conditions mentioned yet class 3 is still noted as a defect. The reality is that if you can not see solder on top side and you have no way of knowing if the 50% requirement is met then how can you say that it is. You would have to perform a cross section to really know if the 50% is being met. Now the question is how many cross sections do you need to have confidence in the solder meeting the requirement since it can not be visually verified? Rich [log in to unmask] on 05/09/2002 01:43:48 PM Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond to [log in to unmask] To: [log in to unmask] cc: (bcc: Richard Carruth/LABARGE) Subject: [TN] PTH Vertical Fill Requirement IPC610 Rev. C Hello, Looking for the groups opinion(s) on the vertical fill requirement stated on page 6-7 of IPC-A-610C. Is the exception pertaining to the Defect Class 3? Therefore making the 50% fill acceptable for class 3, PROVIDING the 360 degree and 100% wetting of barrel walls lead on the secondary side, and surrounding PTH's meet the requirements of table 6-2. What is the opinion of all in the above case "IF" you can not actually see into the PTH to the depth of the 50%, but the soldering is acceptable and meets all the requirements otherwise? Comments privately or to the list will be appreciated. Thanks, Carl Barnes Production Process Analyst --------------------------------------------------------------------------------- Technet 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 Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet 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 Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------