Date 10/7/97 Subject HASL Finish From Maurice Dore To Technet HASL Finish Hi all, I've experienced extreme cases of non-filling of small vias in a wave soldering operation.Microsectioning some soldered PCA's reveals voids in the vias, with copper exposed on the barrel of the PTH at the rear of the void. Microsectioning of the bare boards show large areas of exposed Copper in the barrel of the PTH. All through-hole components and larger vias are unaffected in the process but the bare boards show the same quality of HASL in their plated through-holes. Has anyone seen this, any process improvement hints(I'm using low-solids and this can't be changed???). I've tweaked dwell times to reduce the quantity of defective vias but I am getting PWBs in which are over 5-6 months old and the problems are aggravated with their age. Oh.... prebaking improves quality dramatically, but I ain't got the resources to prebake such high quantity. Any suggestions or hints appreciated. Moss *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************