So I take it from the responses so far that no-one has carried out any testing to determine the length of time they are able to leave electronic assemblies in solvent strip tanks? *Well, yes and no. I occasionally get the same situations that you describe and am asked if the assembly is still good. We do some testing on the hardware to see if we notice any real change or degradation of properties. That becomes part of our experience, not part of the specifications or work instructions for operators. And, the data is only good for that solvent, for that exposure, on that solder mask, on that laminate, etc. It is not an exhaustive testing to determine process windows by any stretch of the imagination. Leaving an assembly in for 'the shortest possible time' is ok in theory but it isn't a specification for operators to work by. Does this mean that we are all relying on manufacturing operatives to make their own decisions on how long to leave assemblies in for (do they have the training to make decisions like that)? *No, the operators do not have the training for that. This is why we employ materials experts or Experts On Call, to answer the questions when they come up. In our work instruction, we do use "minimal time" and so on. The operators understand that. We don't put in "up to one hour" because some might take it the wrong way and use all of that time, if they figure it acceptable. Doug Pauls --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------