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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


pcb solderig

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#59743

pcb solderig | 1 September, 2009

We gold plated PCB and while soldering, the adhesion of soldering is not uniform at the tips(soldering ends).

Please help us to solve the problem.

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#59754

pcb solderig | 1 September, 2009

Please explain "adhesion of soldering is not uniform at the tips (soldering ends)." For example: * Is the "tips (soldering ends)" the component leads? * What is the component? * What is the finish on the component? * What process is causing this issue? * What solder alloy are you using? * What temperature is measured at the component during soldering? * Could you attach a picture?

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#59832

pcb solderig | 10 September, 2009

My guess is that he is talking about the gold plated pads not fully wetting with solder. We have seen this on some of our ENIG boards with the gold still showing at the far corners of the rectangular pads. Not knowing if this is hand soldering or paste/reflow, the causes could be any of the following (and possibly a combination of):

1) Contamination on the pads before soldering.

2) Not enough flux was applied.

3) Not enough solder was applied.

4) Joint not hot enough during soldering, i.e. TAL not long enough.

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