Shirley, That's the nature of the beast. That's why they usually are bonded to aluminum backer plates. You could try to use large flat washers and set the torque requirements quite low (you will need torque requirements). Loctite or equivalent is a must to hold the screw (I am assuming you are screwing through the board to something metal on the other side, other wise you are in serious trouble or I don't have enough information to understand your application and configuration). Good Luck, Bruce Misner > ---------- > From: [log in to unmask][SMTP:[log in to unmask]] > Reply To: TechNet E-Mail Forum.;[log in to unmask] > Sent: Thursday, April 18, 2002 5:32 PM > To: [log in to unmask] > Subject: Re: [TN] Hole cracking of Teflon PCB after screwing > > that even sounds painfull, sorry couldn't resist! > > > > > > > > Shirley Xiao <[log in to unmask]> on 04/18/2002 05:00:47 AM > > Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please > respond to > Shirley Xiao <[log in to unmask]> > > > > > > > > > To: [log in to unmask] > > cc: (bcc: Warren Crow/US/I-O INC) > > > > Subject: [TN] Hole cracking of Teflon PCB after screwing > > > > > > > > > One batch of double sided PCB using teflon materials > have hole cracking problems after screwing by electric > driver.The borad is easy to break if I bent it. Is it > do to laminate quality problem? > What kind of test shall I have? > > Thanks in advance! > > __________________________________________________ > Do You Yahoo!? > Yahoo! Tax Center - online filing with TurboTax > http://taxes.yahoo.com/ > > -------------------------------------------------------------------------- > ------- > > 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 > -------------------------------------------------------------------------- > ------- > --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------