Mr. Windsor: Post your fax number, so I may fax you a solderpaste aperture shape that I use for the complete elimination of solderballs for chip components. It was proven it works better than home plate shape. regards Matthew Park >>> Clinton Windsor <[log in to unmask]> January 7, 1998 1:27 am >>> Dear Technetters, We are trying to eliminate the occurence of solder balls in our production line by trialling various aperture shapes and reductions on the screen printer stencil. The nature of the solder balls suggests that paste is being trapped under the component and then forms a solder ball which adheres to the side of the component. I have seen this type of solder ball referred to as a "squeeze ball". We have tried the so called "home plate" (trapezoidal) shaped apertures with considerable success on nearly all the components except for the 0603 capacitors. I would be interested to hear any ideas or suggestions of other aperture shapes or designs which could help solve this problem. Thanks in advance, Clinton Windsor ############################################################## 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. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################