Andres wrote....
>Sorry for my ignorance, but what is 0402?

When you see a four digit number like this, it's used to describe the
dimensions of a "chip" SMT part (which is a two leaded component, ie
resistor or capacitor).

"0402" is describing a part which is 0.040" by 0.020".

Right now, saying you can do 0402s is strictly a marketing ploy for card
stuffers.

This part is exceedingly small and the manufacturing guys here at Celestica
often refer to them as "Grains of Sand" or other much more insulting terms.
0402s cannot be glued to the backside of a card and wave soldered (they are
so small the glue ends up covering the solder pads or short out due to the
solder bridging over the components).  They are very hard to rework and
often get misoriented in the tape or bounce right out of the feeders as the
reels are advanced.

If you're a test weenie (like myself) you hate them because the paste can
flow and short underneath the part (requiring X-Ray to find/confirm) and
they're so small values can't be printed on the (so you can't tell if the
wrong part was put on by looking at it).

If a customer came to us with a board that had 0402 parts, we would do
everything in our power to get them to respin the board for 0603s (0.060" by
0.030") or greater.

myke
>
>Regards,
>
>Andres
>
>

"My ancestors didn't spend millions of years clawing their way to the top of
the food chain, just so I could become a vegetarian"