Just curious Mark, What are the problems with "replacing small holes with score lines on tab rout designs?" I once had a manufacturing engineer request that an array panel be done this way and the results appeared satisfactory. Tom Martin Date: Thu, 22 Jun 2000 08:58:55 -0700 From: Mark Simmons <[log in to unmask]> Subject: Re: V-score depth MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Dennis, Steve, et al.... i suspect the reason this topic keeps coming up is because of our well intended desire to nail things down. after all, there are so many things to keep track of, eh? By way of review,...there are too many variables to be specific about what the remaining core thickness (web) should be. the chart that Steve recommended from the Accusystems web page, takes into consideration the most variables, but still makes many assumptions. i.e.; the material is FR4, and the score line is not adjacent to SMT component lands. So this chart will get you into the ball park, but you must find your own seat. Here at Vscore Central, we deal with these issues on a daily basis...over the years, we have seen some pretty strange stuff. There is an astonishing lack of convention. There are a number of mis-applications, including replacing small holes with score lines on tab rout designs. Simple things like providing solder mask clearances for the score lines are overlooked. (acrylic masks machine so poorly..) Generally, the process is an afterthought (at best) for most designers...but i digress. In summary, be careful with "rules of thumb". Mark Simmons, V-Score Central, Inc. ############################################################## 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 Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################