SMT hand soldering on HASL or Ni-Au boards?

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Hi, Our engineering board has to decide which technology ... - Apr 03, 2001 by SV

With friends like you, who needs enemies? I�d guess that ... - Apr 03, 2001 by davef

#5843

SMT hand soldering on HASL or Ni-Au boards? | 3 April, 2001

Hi,

Our engineering board has to decide which technology is better for the hand soldering of the SMT components: HASL or Chemical Ni-Au.

We have an automatic line for SMD assembling and our experience shows us that for this automatic line is better to use Chemical Ni-Au. The problem now is that in our group of companies there is an other company that uses especially HASL for their boards. We have to decide which technology is better, taking into account that the big quantities shall be assembled on our automatic line and that the small quantities could be made by the other company which uses hand soldering. We want to have a complete exchangeability between our products, so that each of our products can be assembled there, manually, and each of their products can be assembled to us on our automatic line.

Knows someone which are the disadvantages of HASL for automatic SMT assembling, for hard metric press-in connectors, for boards with a thickness bigger than 3.2mm? Are there disadvantages also for Chemical Ni-Au?

Thank you very much, Sorin.

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davef

#5847

SMT hand soldering on HASL or Ni-Au boards? | 3 April, 2001

With friends like you, who needs enemies?

I�d guess that the perceived benefits of flat pads for your 20 mil pitch and below components counter-balance the higher cost, gold being a solder pot contaminant, limited solder mask compatibility, potential reliability, and lack of reworkability problems of ENIG in some of your plants.

So, cozzin� up to those issues is a tough sell to your HASL users, eh?

Listen, who cares if you use more than one solderability protection on your boards? We run boards with every finish known to persons [must be PC, yano? orzit people? Whatever!!!] in our plant. We have several different profiles tailored to the board being processed on our reflow oven and wave solder machines. AND the surface finish has dip [er, close to dip] to do with the selection of a profile for a particular assembly.

I want to say the Merix has one of those nifty tables that compares the various surface finishes, but I can�t find their site. No BIGGIE. I imagine that Florida Cirtech, Hadco, and all the rest of those cats offer similar comparisons on their sites.

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