13 Apr
2010
13 Apr
'10
2:02 p.m.
On 13 Apr 2010 at 13:03, dwight elvey wrote:
Rivets are usually to wide to use on IC pins with
traces between. I
wonder if a little of that window stuff would be a good substrait for
plating. Another though would be to use an electroless silver plate
first and the copper.
One doesn't have to do exactly what the shops do.
The shops generally follow up the electroless copper (which really
doesn't lay down much metal) with a full copper electroplate and a
mask that's removed after plating. If you're doing a thousand
boards, this is practical, but onesy-twosy would be a major pain.
Some light on this subject is shed by the LPFK literature. You
recall that these are the folks who make the rapid-prototyping
desktop PCB milling machines. Clearly, they have an interest in
making good vias on their boards.
They offer a low-cost solution that essentially squeegees a
conductive polymer into the vias. The downside is that you can't
solder to it, nor use it as a component hole.
The other two are the real deal--a 4 step process, with the final
being electroplating.
They also make a rivet system with some very tiny rivets indeed
(EasyContac). But the cost will cause you to shudder--$475 for the
basic kit and $0.10 per rivet. A few DIPs or PLCCs and commercial
PCB house prices start to look pretty good.
Best regards,
Chuck