the time between SMT & wave should be as short as possible but at a max it is controlled by strictest MSD part, so if you have a part with only a 48hr MSL window then it needs to be with the 48hrs. Can you post images of what you are getting? It may be contamination, too much / not enough flux at the wave it could be going through the wave too quick, what is your wave contact time for both chip wave & main wave? have you measured the flux weight? you may have glue contamination on the parts as well. If you are getting bridging is that on the same components or other components? could it be dewetting? are your parts going into the wave square or at an angle, more info would be useful.
reply »