you are absolutely correct Mark. let your PCB suppliers adjust the gerber to meet your finished line specs. everyone has a little different etch factor. ______________________________ Reply Separator _________________________________ Subject: PWB artwork Author: [log in to unmask] at corp Date: 11/16/95 4:36 PM I have a question for the Printed circuit Manufacturers. First a little history. The PWB design group in my company adjusts the artwork (track width & Spacing) to conpensate for the loss of copper during the etching process. I have a concern that the etching depends on each PWB manufacturers process and that each manufacturer would like to make his (or her) own adjustments to the artwork / gerber data to achieve the final engineering requirements Which we also specify on the drawing (Example shown below) Minimum conductor spacing: External layers to be .008 inch after plating and fusing or solder coating. Internal layers to be .008 after etching. Minimum conductor width: External layers to be .010 inch after plating and fusing or solder coating. internal layers to be .010 inch after etching.) I feel that we are over controlling the PWB manufacturers. Is this true? Please provide feedback. Thanh you in advance. Mark Foster Address: [log in to unmask]