Mak, Ideally there is no water in conventional no-clean fluxes (ie 96-98% alcohol), but by Karl Fischer titrations I have found that typically there is 0.15% water in no-clean fluxes. This should not be too surprising as water and isopropyl alcohol are "cousins" and the old rule of "like dissolves like" is alive and well. This level will not hurt your process. If you are using a closed container spray fluxer then you should have few problems due to water. However, if you are using a drum spray fluxer or are still stuck with a foam fluxer then it is another story, especially if your plant is not air conditioned. On a hot, humid North American summer day the water content can continually rise and I have seen it get as high as 2% when people did not look after their system. You will have a whole pile of trouble at this level. 1% is not very good either. I am not prepared to give you the definite cut-off between 0.15 and 1% where action is required. Besides the obviously danger already alluded to in other e-mail replies about flash evaporation of water at the wave, excess water can fool people who are using specific gravity to monitor their flux activity. People could end up adding more thinner because they thought they had a flux concentration problem when it was a water uptake problem. My first recommendation would be to change to a new spray fluxer. Quality will be as good or better than with older fluxers and you will save enough in flux costs to pay for the spray fluxer in short order. I would then change over to a no-clean, VOC free flux for safety, insurance and environmental reasons. We went through a couple and then have found one we love and have changed our whole plant over to it and now two other sites as well to the same new flux. Another few are using another popular one from another major flux supplier. One thing to keep in mind with the new VOC free fluxes is that not only do you often need more preheat, but the air-flow patterns in your oven are important to help remove the saturated air/nitrogen so evaporation can continue. Good luck, Bev Christian Nortel > -----Original Message----- > From: [log in to unmask] [SMTP:[log in to unmask]] > Sent: Tuesday, January 05, 1999 12:11 PM > To: [log in to unmask] > Subject: [TN] Water contents in no clean flux > > All, > > Would like to know if fresh no clean flux should contain water. If > yes, what is the purpose and what is the appropriate level of the > water content? > > Appreciate if any suggestons. > > Mak > > ################################################################ > TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c > ################################################################ > To subscribe/unsubscribe, send a message to [log in to unmask] with > following text in the body: > To subscribe: SUBSCRIBE TechNet <your full name> > To unsubscribe: SIGNOFF TechNet > ################################################################ > Please visit IPC's web site (http://www.ipc.org) "On-Line Services" > section for additional information. > For technical support contact Hugo Scaramuzza at [log in to unmask] or > 847-509-9700 ext.312 > ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################