PCBs with multiple colors of silkscreen/solder mask?

Hi there - recently a rep brought by a PCB that was showing off one of
their connectors. On the back of it there was some silkscreen
describing the connector and giving some other information. What
caught my eye was that the silkscreen was in something like 3 or 4
colors! Has anybody ever seen this before? Is it common for a PCB fab
to be able to do this? Is it very expensive?

Also - has anybody ever seen a board with multiple colors of solder
mask? I mean, how cool would it be to have a PCB with white and black
striped soldermask? Or even a houndstooth pattern?

Most of my PCBs end up in very visible locations so this actually
matters to me, as trivial as I expect it will seem to most of you.

Thanks!

-Michael

 

You'd need a silkscreen gerber file for each color, same goes for
soldermask.
It would be expensive since they would have to stop the machine,
change the color of lacquer, flush the machine through with the new
color, etc...
Silkscreens are less intensive but you still need to make the
silkscreen and call out the different colors.
Call your local PCB shop and discuss it with them, they're usually
open to all kinds of creative fiddling.

 

I wouldn't call it "common", but there's nothing to prevent you from
running the board through as many layers of silkscreen you want to. You'd
have to do the color seps, of course, and get the screens made, and either
have somebody do it or build a frame with registration and do it yourself.

For cost, probably a little less than 3X or 4X the cost for one color.

That's a different story, unless the solder mask is screened on, then
see above.

I think you can order board material in different colors - you could
also look into electroplating, etc.

But you can silkscreen anything you want!

Good Luck!
Rich

 

More likely the additional colors would be done at a silk-screen shop,
since the average PCB fab house seems to generally silk screen in any
color you like so long as it's white.

 

Multi colour solder mask is also a possibility. No different to the silk
screen process.
Don't use black/grey, you cant see solder whiskers through them.........

 

Not my forte', but a place I worked while in college had a rather
impressive PCB that was Royal Blue in color, with gold-colored solder
joints. Not sure how they did it, but it was really cool to look
at...

-mpm