Reading the sometimes confusing dialogue on this subject, it is once again clear that there is an aching need for this industry to abandon its more archaic and arcane measurements, such as the use of weight to define thickness, and instead use metric values. While realizing that there are years of convention and countless articles, books, standards and specifications using such terms but it does the industry no good to perpetuate an erstwhile "secret handshake" convention that was used originally to make easier the sale of metal foil by weight to users of all stripes, from artisans to roofers. It is time for those of us the USA to come of age, join the world and convert to the much more logical and useful metric measurement system at least within this industry. While one can already hear the arguments of cost of conversion, I don't think anyone is keeping a running tally of the cost of the many errors and countless clarifications that surely are occurring hourly (and the likes of which we are witnessing here). It's time for a change that is long overdue. To that end, maybe everyone in this forum could start by supplying metric values first in these conversations and for some time to come put the older, less logical measurement values in parenthesis following the metric value for historical reference (or for those who still find comfort in the old ways). We seem to have done a good job in converting to metric temperature values for assembly. From that one gains confidence that we can succeed in the other measurements as well. All that is required is will. The change will eventually come most certainly, it is just a matter of time and dedication to logic and principle. Kind regards to all, Joe --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------