Mike, Basically, this boils down to 2 issues : what the user really want/must have and what your HASL machine can give. So, pls consider the following suggestions : a) where is the point of measurement - center of pad, crest of solder, XX% from pad edges, etc.. b) what MUST be measured, should be measured, nice to be measured, nice to have, etc.. c) what are the user's conditions like - long storage, multi-reflows, board make-up and density, etc.. With one HASL setting, there will alway be compromise. Generally, we measured both 'large' areas (eg: PLCC, gnd, ....) and 'small' pads (QFBs, ... .). Solder basically will range from 70 - 1000 umil, so getting 90-100 on larger areas is pretty impossible all the time (unless you turn off the air ! ). Small pads, on the other hand, hit above 100-200-300 easily but may tend towards the higher end which can be a concern with customers. However, 1000 umil should be a very comfortable limit (BUT.....there didn't seems an end to this issue). Likewises, I would be happy to heard from anyone on HASL woes & fixes, realistic specs., etc... Season Greetings to you and all. Joseph Yip _____________________________________________________________________________ __ To: [log in to unmask]@INTERNET From: [log in to unmask]@INTERNET on Mon, Dec 23, 1996 11:42 PM Subject: HASL Surface Tolerence Can anyone tell me what is the specs for the surface of pads after HASL. I know that it will not be perfectly flat but what is the spec. Merry Xmas to all Mike Lopez *************************************************************************** * TechNet 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. * *************************************************************************** * 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] * *************************************************************************** *************************************************************************** * TechNet 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. * *************************************************************************** * 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] * ***************************************************************************