Please foward this message to it's appropriate location. Our company has been manufacturing a double-sided SMD pcb using an IR solder process. We have been using the same no clean solderpaste for the last few years. Recently we changed pcb vendors for cost reasons, and the new boards seem to have a higher degree of solder flux residue migration. The problem we have is with the hardened flux on the testpoints and the difficulty in penetrating it consistantly. The only difference in the pcb's from the new source is in the soldermask. The new boards have a Hysol screened Wet mask that has a rough texture to it. The previos boards had a LPI soldermask that was glossy and smooth in texture. My question is, why would the difference in soldermask applications cause a higher rate of solder flux residue migration? Any insight at all would be greatly appreciated. Thank you. Eric L. Johnson Sr. PC Designer Nartron Corp. [log in to unmask] **************************************************************************** * The mail list is provided as a service by IPC using SmartList v3.05 * **************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ****************************************************************************