For anyone who would like a diversion from the assembly processes, I have a different question. My Army customer is simulating field testing of a weapon system to check the abrasion resistance of some treated metal surfaces (tungsten carbide) that rub together during flight. The 'sand' that they are using to contaminate these areas is aluminum oxide. Needless to say, excessive scoring is observed on the metal faces. My contention is that sand is primarily quartz, or silicon dioxide, which is softer than the Al2O3, and the system is being over-tested. Anyone have a notion of the acceptable sand type used in environmental tests? Thanks Ralph Vaughan Boeing-Fleming ############################################################## 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 Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################