Joe, The problem you mentioned using tin/lead board finish is nothing new ( from what I can remember working for my previous empolyer a long ago). Wrinkling of boards is very problematic in addition with non-wetting surfaces. You may need to scrub your bare boards prior the assembly. Get yourself a bunch of good brushes.... Try soaking tin/lead finish bare boards in alcohol-based or flux removing solvent. This will remove grease and foreign contaminants. You will see solderability improvement for wavesoldering. Using a more active flux is another option for that finish. RMA flux (high solid content) or water-soluble flux will definitely work good but need freon cleaning or washing. regards Matthew Park ############################################################## 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. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################