Let us count the ways, sorry just a little joke. In my last bit of advice I suggested that the problem could be fixed by increasing the resin to glass ratio. But too much resin not enough glass can make your package slip. When was the last time you checked your press for parallelism? You might be pushing the package to one side or corner. If your gel time is off the prepreg can get very slippery. How many layers? Are your making a multilayer that has little "C" stage core and very much prepreg. Do you need to block the load. When we last used vacuum assisted lamination I made some aluminum frames to assure the load was centered and resisted slippage because we use some conformals that can cause slippage when the stack was higher. When we do not use the vacuum assist we reduce the stack height. Dan Brandler, where are you? You should probably have some insight for this guy. Chuck Brummer [log in to unmask] Wang, William (Suzhou Laminate) wrote: > I'm a greenhand of copper clad laminate, can anyone tell me why > copper clad laminate could slip during press and how to prevent from > slippage? (We use vacuum assisted hydraulic press) > > Thanks and best regards > William Wang > > ############################################################## > TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c > ############################################################## > To subscribe/unsubscribe, send a message to [log in to unmask] with following text in > the body: > To subscribe: SUBSCRIBE TECHNET <your full name> > To unsubscribe: SIGNOFF TECHNET > ############################################################## > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information. > If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or > 847-509-9700 ext.5365 > ############################################################## ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################