Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

No clean flux residue



No clean flux residue | 1 June, 2001

Our PCBs manufactured with no clean flux have a waxy film on the this normal? Our contract manufacturer recently switched to no clean from water wash. Thanks Carl

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No clean flux residue | 1 June, 2001

No clean residues can range in appearance from brownish gunk that looks like tree sap (because it is in some instances) to almost no residue at all. Is this product exposed to a wave soldering process or SMT? I would guess it's a wave process if the entire surface is waxy. Anyway, what you're experiencing is perfectly normal and is indicative of some no clean fluxes. Please find out what Flux (mfr and part number they are using and I may have a better idea of what you're experiencing)

Regards, justin

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No clean flux residue | 1 June, 2001

Your supplier�s approach to managing process change is TOTALLY UNACCEPTABLE!!!! Now, let me get the froth back in my mouth.

How in the world do we know if the residues on these "no-clean" boards are compatible with your product?

J-STD-001C, para 4 says words to the effect of: The materials and processes used to assemble / manufacture electronic assemblies shall be selected such that their combinations produce products acceptable to this standard. Objective evidence of this compatibility shall be maintained and available for review. When major elements of the proven processes are changed, (e.g. flux, solder paste, cleaning media or system, solder alloy or soldering system) validation of the acceptability of the change(s) may be performed and documented in accordance with Appendix B.

If I was your customer and you sent me product with a board that later failed, I�d surely determine from you that you checked-out the new process materials to be sure that there was no effect of it on the final performance of your product. If you didn�t do that and it affected the performance of the product, I�d be calling Johnny Cochran. And Johnny would be saying "Since Carl didn�t give it a good look, now you must get-out the checkbook!!!"

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No clean flux residue | 4 June, 2001



The best thing to do is find out at which process this "wax" is occurring at. Targeting the process that just changed may be presumptuous on your part. Pick up the phone or make a visit. In either case, you're the customer and you're not satisfied.

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