Steve, there are as many reasons for x-outs as there are board shops times the number of operations that each board shop performs. Just a few examples: 1) When the lamination press operator accidentally bangs two panels together and one gets a nick in the copper, the board ends up with an open that fails electrical test and that board is x'd out. 2) When a drill bit breaks off in a hole, the drill machine will stop and the operator can replace the bit and restart the machine. The panel is good, but that one circuit with the bit lodged in the hole cannot be saved. 3) When the print operator aligns the artwork a bit mis-registered only those holes that are slightly off center due to drill wander will break out of the pads and the rest will be good. Some boards pass test, and some get x'd. When you tell the board shop no X's they have to eat the cost of all rejects so your price per image goes up. When you accept multiple X's your assembly cost goes up. The trade-off is yours to make and negotiate. The opportunity is yours, however, to have products designed that give the board shop high yields. Most designers don't consider plating thief as a part of design. If the board shop asks to add thief the answer is usually that either the designer is too busy working on the next generation or the design is frozen and can't be tampered with for fear of crosstalk or changes to signal timing. Another isssue that affects yields is spacing. All designs are run on an autorouters. Routers accept rules up front about minimum conductor widths, pad sizes and spacing. When a designer starts the router with a minimum space of say, 5 mils specified, the computer starts running the first track at 5 mils from the nearest pad. When it finishes running it doesn't go back to find out that there were no more lines run and that that first track could have been spaced out further to reduce the risk of shorts. Efforts made to review designs for maximum uniformity of density and maximum spacing between lines and pads will pay off in improved yields and reduced costs. Ps. If you bring your Duck to Virginia I'd love to drool all over it, but I quit biking 15 years ago when my last one was stolen and I don't need to get hooked on an expensive hobby again. ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################