Steve, no need for the Std Improvement Form for this now--I'll take a copy of this message when I leave Wed afternoon for committee meetings this week; DPMO 9261/7912 here in Northbrook tomorrow and Wed, then A-620 Thurs/Fri; A-610 Sat/Sun and HDBK-610 Monday. All meetings in Hunt Valley, MD, graciously hosted by Teresa Rowe at AAI this time. No additional meetings scheduled at this time but Greg Hurst, BAE Systems, Austin TX and Mel Parrish, Soldering Technology International and Vernon Judy, Qualastat Electronics, Gettysburg PA have invited the committees to meetings at their facilities. Cordially Jack >>> [log in to unmask] 05/13/02 07:32AM >>> Jim, Guy, Nancy and others, I respectfully submit the following: If the intent for the 50% hole fill allowance (in regard to PTHs with thermal or conductor planes) is to be limited to class 2 then the exception should be listed directly under "Acceptable - Class 2" not under "Defect - Class 3" on page 6-7 and table 6-2 should have a note that flags this allowance for Class 2. As we all know, it is impossible to clearly and concisely write with the English language in such a manner that all readers will properly understand the meaning or intent of the words that is or are being conveyed. Having not participated in the IPC-A-610 meetings (as Guy referred to), I and others do not have the luxury of understand the intent of certain requirements -- all that is affored to us is the written words. In this case, the intent may have been to limit the 50% hole fill requirement to class 2 but the printed words do not support this beyond the shadow of a doubt. I will prepare a Standard Improvement Form for IPC-A-610C and forward to IPC so the committee can fill more hours with antiquated prose about this subject. I on the other hand still believe that 50% hole fill on most class 3 products will not cause a problem in terms of long term reliability even under extreme conditions as apposed to reworking the solder connection. This statement is made under the premise that a well defined, developed and controlled process is utilized. If there is any objective evidence that 50% hole fill is a problem, I along with Sir Werner would like to review the data, hardware, photomicrographs, cross-sections, etc. Steve Sauer --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------