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What are some unforeseen side effects using glue to fix SMD pads and traces that have been lifted off from the PCB board. It was for 0406 caps, the cap is soldered on the pad but both pads are lifted off the board and hanging like a bridge. About 2mm of trace after the pad was also lifted. We rejected the boards that are damaged, but the fab house send it back to us after they fixed. They poured epoxy glue over it to fix it. Doesn't anyone know any side effects that might arise from this kind of fix??

Thanks for your help! Ping

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    \$\begingroup\$ Take a look at the following two guides: circuitrework.com/guides/4-1-1.shtml circuitrework.com/guides/4-4-1.shtml . The skinny of it is that it most likely an electrically conforming repair, but depending on IPC class you specified cosmetic issues may be reject worthy (process indicator for high-reliability assemblies). However, if you don't specify IPC Class 3 they won't follow it (and if you do they will charge much more), and cosmetic issues are typically not a reject under Class 1/2 \$\endgroup\$
    – crasic
    Feb 16, 2016 at 19:29
  • \$\begingroup\$ In most situations the epoxy fix will likely outlast other components if the choice of expoxy is reasonable. \$\endgroup\$
    – KalleMP
    Feb 16, 2016 at 22:05
  • \$\begingroup\$ ...you might choose a different fab house next time...could be a side effect for them. \$\endgroup\$
    – Ecnerwal
    Feb 16, 2016 at 22:40

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If the repair point is visible, the negatives would be aesthetic only.

Your PCB is manufactured by using epoxy resin to bind the layers together, so using it to re-bind a trace to the substrate is not a problem at all. The only negative would be if the repair was not done very cleanly and looked bad. There wouldn't be any functional difference.

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    \$\begingroup\$ Agreed..._unless_ they 'potted' a heat-producing component with an insufficiently thermally conductive epoxy in the 'fix.' \$\endgroup\$ Feb 16, 2016 at 21:53

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