Painting circuit boards

[Screech]

I want to paint the component side of my circuit boards (thru hole technology).
I'm doing this because my boards are semi transparent and I dont what to see the tracks thru it.

Can I use acrylic or enamel spraycans?
Is it ok to do this?
Thanks

 

[Klaus]

Did you want to paint the boards before or after they are assembled?
If before, you are better off using a silk screened mask of solder resist, the green stuff you see on commercial boards. Why silk screened? you have to leave the pads blank for the solder.

If you want to paint after assembly of parts then I guess any paint that will NOT attack the components would be OK. It might make it very difficult to troubleshoot the board later on, with everything coated in paint.

If it was me, this would end up being too much bother :wink:

 

[Joel Rainville]

I want to paint the component side of my circuit boards (thru hole technology).
I'm doing this because my boards are semi transparent and I dont what to see the tracks thru it.

Can I use acrylic or enamel spraycans?
Is it ok to do this?
Thanks

Why don't you put the whole circuit in a plastic/metal enclosure instead of messing with paint?... Why do you care about traces showing anyway?

 

[mstechca]

If you don't want to see the traces, then dip it in paint, as long as nothing is screwed up afterwards.

But if you are painting text, you should engrave it in copper. In other words, make it part of your circuit design. Just make sure the text does not touch the tracks.

 

[MrMikey83]

Most paint isn't conductive (after it dries). If you dont want the components painted, you could take some white glue and coat each component. Wait for the white glue to dry and then spray paint however you want. Then, when the paint dries, the white glue should peel off the parts. You can also use liquid cement which may come off easier after painting.
~Mike

 

[zevon8]

You could always get some conformal coating spray, seal the board with it, then paint what ever color you want.

As an aside, many conformal sprays containan a UV dye so you can inspect for coverage. It glows violet / purple under UV or even sunlight/flourescent light. Your entire pcb will glow for people wanting the effect in modified PC's with case windows.

 

[Screech]

Ok, Firstly, I wanted to paint the board before the components were placed on the board.

Does the paint have to be static resistant?
Don't think anyone sells static resistent paints.

Where do you buy silk screen paint for pcb's?
Thanks

 

[zevon8]

Ok, Firstly, I wanted to paint the board before the components were placed on the board.

You will need to mask all the soldinrg points, so you will need a solder mask screen made from your PCB artwork. This is a comon mask, available in most layout programs.

Does the paint have to be static resistant?
Don't think anyone sells static resistent paints.

Antistatic paint would likely be conductive enough to cause problems in many circuits, it is often the same paint used for sheilding, so it is just carbon laden paint. Not likely what you want or need.

Where do you buy silk screen paint for pcb's?
Thanks

Many art supply stores sell silk screen inks and supplies, and there are some who will do artwork for screens, and even make screens for you. This is not all that cheap though, especially for a small project. Silk screening is an aquired talent, probably more than you want to do for a single board.

There are solder mask pens available that you can use to mask holes before painting with a spray can. This would work if it was not too complicated a board. These pens are sold by places like Digikey, etc. the are for rework and touch up during repair. This may be an option. Some pens are alcohol solvent, some water based, depending on the process needed. You apply the pen's fluid to anywhere you want covered, then paint, then remove the pen marks with either water or alcohol depending on the pen.

If it is worth it, you could check out a PCB maker that specializes in "prototype" runs of PCB's. They often have a flat rate for a certain board size, so what ever you can fit into the area, you can get done in one shot. This can include plated through holes, reflow of traces, soldermask, and part labels. There are a few online places that do this, you send them the files from a PCB program, and they send you back finished boards.

To do it yourself, you will need a bit of set up, and if it something you are not likely to do very often, it may be cheaper and more efficient to have someone do it for you. I know this takes all the fun out of it, but if it is a "one-off" you have to consider the materials and equipment investment to do it yourself.

 

[Screech]

Zevon, thanks for that lenthy reply,

Antistatic paint would likely be conductive enough to cause problems in many circuits, it is often the same paint used for sheilding, so it is just carbon laden paint. Not likely what you want or need.

so, your'e saying, any paint that does not conduct electricty is fine, and will not effect the electronics.

would there be a danger or static from your fingers if you were to touch the paint, and damage the electronics?

also,
When an ic's pins are all soldered on, is it safe from static?


This is an automotive circuit wich will require the driver to get at the circuit board for periodic ajustment.
thanks

 

[zevon8]

In your application, I think I understand all you are trying to do is protect the PCB from damage because it is an automotive environment. If this is the case, then I would suggest that all you need is a conformal coating, preferably something flexible like silicone.

If there are adjustments required periodically, then a small sticker or vinyl label could be placed over any trim pots or similar, then coat the PCB with a silicone conformal spray.

This is one I use daily at work, ont everything from terminal strips to PCB's that are being installed in trucks. It is very durable, easy to apply, and can be removed for circuit repair, and is easy to reapply over repaired areas. It is clear, but that is fine, since there is really no reason to try to hide a circuit board anyways. Anyone who really wants to copy a design will do so, painted or not. Nearly anything you can think of to cover a circuit can be removed, either mechanically or with the proper solvent.

If you used somthing like this, the circuit should be fine, safe from danger of being touched, etc. If will basically be covered in a layer of silcone, as if dipped in thin silicone caulking.

Here is a link to the stuff I use, it costs about 8 dollars a can, goes a long way, about the same a similar sized can of spray paint:

https://www.mgchemicals.com/products/422a.html