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HASL on Pads

Dreamsniper

#29096

HASL on Pads | 14 June, 2004

I have boards with bad HASL application. First they're not even. Second some pad edges have no HASL and still remains bare copper. What's the maximum and minimum HASL thickness required for a good solderability. My boards are about 6 weeks old, I know that HASL thickness dictates the shelf life of the PCB (correct me if I'm wrong) and is my board still considered OK?

thanks and regards,

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#29099

HASL on Pads | 14 June, 2004

HASL Thickness: * HADCO DFM manual specifies a nominal thickness of 50-1500uin with an option for 100-1000uin * Merix DFM manual specifies 30-200uin

IPC-6012, Class 1, 2, 3 do not spec a HASL thickness at all but only require that full coverage is made and that the board meets solderability requirements.

We'll bet money that those unHASLd, copper areas will not take solder. Get rid of the boards.

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Dreamsniper

#29103

HASL on Pads | 14 June, 2004

Can I manually tin them with solder specially the BGA's. Will that improve the solderability? What about corrosion of the copper? will it be prevented with the above process considering that after tinning of solder the solderability became acceptable (IPC Class 3)?

thanks

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Ken

#29107

HASL on Pads | 14 June, 2004

Um...I would reject those boards. skip plating is a process indicator...a bad indicator. IF your building to class 3...I would get the rep in ASAP and reject the lot.

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