Has anyone tried painting or changing the color of a pcb?

[alank2]

I'm thinking of using this in a project:

http://www.mouser.com/images/electronicassembly/lrg/EA_LED94x40_A_DSL.jpg

It is a backlight to an LCD display and they put it on a white pcb.  most of it will be covered by the display, but perhaps 4-5mm on the top and bottom won't be.

Has anyone tried painting or changing the color of a pcb like this?  I don't think I'd like how it would look against a shiny black pcb, but that is the color I'd prefer for the project.

Paint it?  If I paint the top of a pad, will heat/solder melt off the pain for 6 connections?

Ideas?

[Ian.M]

Some black paints are partially conductive.  Expect trouble!

[PDXjason]

Is it part of the aesthetic, or did you not want to make a black enclosure for it?

[alank2]

Yes - I was it to be without enclosure, so the pcb is part of its look...

I thought about just using a white pcb, but I'm not sure I want to do that either.

[@rt]

Your location isn't shown.
In Australia, White Knight spray enamel in
the non metallic colours has no metal content,
and can be used around very high voltages.

[alank2]

I'm in the US.

[james_s]

I've painted PCBs once or twice, had no trouble at all. I masked off pads I had to solder. As with most things YMMV but it worked for me.

[alank2]

James - what type of paint did you use?

[james_s]

I don't remember, it was whatever spraypaint I had on hand. Some type of epoxy enamel.

[alank2]

I suppose this is what scrap boards are for, to do some testing!

[@rt]

Oh ok, I did mine after the board was populated.
Also used some for some parts of a Tesla coil which
is why I contacted the company.
I wanted to know if the non-metallic paint contained any metal,
and also if the metallic paint contained any ferrous metal.

[Gregg]

Many black paints / non-dye based inks use carbon black as the pigment, and carbon black can be conductive in some paint/ink formulations.  So not only "metallic" paints could be problematic if applied over circuits.

Soot is a pretty effective black colorant for PCBAs.  Maybe if you add more magic smoke to it than it already had it'll actually work better...

Solid state magic smoke, why didn't I think of that?  It could be the answer to replacing the elusive magic smoke in Lucas electrics.

On a serious note, the PCB could be sprayed with Krylon Crystal Clear before painting it black.  I have had good results with Krylon in the past, but I think they have changed the formulas recently to conform to environmental regulations.  Walmart sells Krylon spray paint.  You could spray some black paint on a plastic backing and test it with a megohm meter. 

[RGB255_0_0]

If you don't mind a shiny surface, maybe nail varnish?

[PointyOintment]

Cover it with black paper or plastic sheet?

Somewhat off-topic: I saw a product on DX once where they had inkjet-printed a camouflage pattern onto the PCB. I think it served as the solder mask. I think it was a color sensor breakout board.

[RobertHolcombe]

If its viable you could apply conformal coating prior to painting, assuming the paint will adhere

[Harb]

Get a large black Artliner or Texa marker pen, screw the end of it and pull out the innards......rub the black fluffy piece on the board, and presto, you will have your black PCB

[tautech]

Use a black conformal coating, one of Electrolube's products come in red or black.
http://www.electrolube.com/pdf/conformal-coatings-brochure-electrolube.pdf

If conductivity of a paint system might be a problem use any conformal coating to seal it then apply a colour of your choice.

[alank2]

Thanks for the good ideas everyone; this gives me a few things to try!

[Zero999]

Many black paints / non-dye based inks use carbon black as the pigment, and carbon black can be conductive in some paint/ink formulations.  So not only "metallic" paints could be problematic if applied over circuits.

Soot is a pretty effective black colorant for PCBAs.  Maybe if you add more magic smoke to it than it already had it'll actually work better...

Soot is carbon so is likely to be slightly conductive. Whether slightly conductive paints/pigments are a problem or not, depends on the voltages and resistances in the circuit. It it's a low voltage circuit, with low impedances, say under 30V and 10k respectively, then a few M Ohms of parasitic resistance won't be a problem.