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MELF's falling off

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TM

#44574

MELF's falling off | 17 October, 2006

I've got some MELF packages that reflow and connect but later fall out of the solder pretty easily. We are not using epoxy but, the parts have fillets per IPC standards. We have not looked at cross-sectioning for IMC and don't plan to at the moment. Any ideas as to why?

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#44580

MELF's falling off | 17 October, 2006

Define "pretty easily". Did anyone ever do whatever is making them fall off now before? In most casses where a component "falls off" then someone implements a totally subjective test to make sure the rest of the parts wont "fall off" they damage a lot of boards before they realize that the mechanical strength of solder joints is not equivalent to pulling apart a chunk of stainless steel, as for some reason most people suspect. Kinda like pushing on fine pitch leads to test thier strength and finding out they are not very strong now, because they never were.

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#44591

MELF's falling off | 18 October, 2006

Have you tested the solderability of the inbound components per ANSI/J-STD-002, Solderability Tests for Component Leads, Terminations, Lugs, Terminals, and Wires?

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