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Voids in thru-hole solder joints

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#52495

Voids in thru-hole solder joints | 13 November, 2007

I have a thick board with ground planes that will be soldered by hand with a mildly active solder/flux. X-ray confirmed that solder was added to the top of the joint causing a void between the bottom and top solder joint. Other than the mildly active flux being entrapped, what other potential reliability issues does this create? What recommendations does anyone have for rework? Thanks.

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#52508

Voids in thru-hole solder joints | 13 November, 2007

This processes has the potential to cause barrel cracking and pad lifting, because the heating is very hot [troop crank-up the volume on their iron when they see thick boards] for a relatively small area on one side of the board.

What do we suggest as an alternative? First, educate your troop that 75 percent barrel fill is required. Then: * Wave solder with good fluxing, long preheat, long contact time * Stencil printing and reflowing paste * Use fluxes with higher solids content, higher acid values

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#52512

Voids in thru-hole solder joints | 14 November, 2007

How about your bare pcb handling? do you stuff smd component prior hand soldering? you can try to bake the pcb and then see if this problem still exist.

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#52514

Voids in thru-hole solder joints | 14 November, 2007

Yes. Baking boards is best. Hitting the hamer on the head!

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