Hi All, I received a call from one of my customers today on a subject I do not have the answer for. I also do not have access to any of the IPC standards that would have the answer to this question, as I am part of a design services bureau and not a fabricator or assembler. I was hoping that one of the more knowledgeable (than I) members on this forum would be able to give me some sort of guidelines, even just a general one, if possible. The question is as follows: "I'm trying to find out what the maximum recommended compression force would be for bolting a circuit board to a metal bar, for the purpose of making a 70 amp electrical connection. My concern is not damaging the board (an 8 layer board, in this case), and not causing the TG170 FR4 material to flow out from underneath the bolt and washer. I realize that the answer may depend on the total thickness of FR4 material and the total thickness of copper in the stackup....." I have already done some poking around in the archives but have not come across the answer, as of yet. Therefore, I defer to the expansive knowledge of those on this forum...... Thanks in advance, Dharma KAW/USA Ltd. 39 Simon Street, #4 Nashua, NH 03060 603-886-8711 x212 603-881-8763 fax Confidentiality Notice: This email and any accompanying documents contain information that is confidential, privileged or exempt from disclosure under applicable law and is intended for the exclusive use of the addressee. This information is private and protected by law. If you are not the intended recipient, or have received this email in error, you are hereby notified that any disclosure, copying, distribution or use of the contents of this document in any manner is strictly prohibited. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 -----------------------------------------------------