Curious, very curious ...
Residues � Where are these residues? [solder & laminate / mask, solder only, laminate / mask only] What is the result of your analysis to the residues? How do you know it�s a flux residue, rather than a chemical by product of the flux and metal oxides? Why isn�t this residue forming during the soldering process when the temperatures are presumably higher? Or could it be: the residues are forming during soldering and they are just becoming noticeable during cleaning? Have you monitored the temperature of the component leads where the residue is forming throughout the process?
Flux � What flux are you using?
Recommended cleaning solutions � What were the three flux manufacturer recommended cleaning solutions? How were these solution applied? What were the results?
Washer � What washer are you using? What is your hot box temperature? Why doesn�t the hot box shut down when the conveyor shuts down?
If these are baked flux residues, � * Water soluble fluxes can form water insoluble decarboxylated and polymerized substances when heated. * Mild alkaline solutions such as dilute saponifiers can help in removing oxidized and decomposed water soluble flux acids.
Remember: A decrease in wash water temperature of 10�C can reduce the cleaning rate of your washer by 50%. So, you may have a bigger problem than you think.
So, here's the scoop ... find a saponifier salestype ... find out if it thinks its materials will clean whatever you think you've got [of course it will say it can do the job] ... talk to a technical type to make yourself feel comfortable ... tell the salestype you want assess it's chemicals by running a coupla boards through their lab ... get your boards cleaned ... say pfew!!! Live well live long.
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