Cleaning PCB's

Looks like a motherboard made around December 09 with ISA interface.  Does it work?

Looks more like PCI to me.  I'd also say it's more likely a custom board rather than a PC mother board since the latter tend to be more crowded.

For cleaning, I'd go with rubbing alcohol and Q-tips, or those alcohol-soaked pads you can get at the pharmacy.

Hi Neil,

If it is just dirt I usually just use compressed air and a soft bristle brush. As long as the dirt isn't conductive its only real harm is that it can insulate components and not allow them to cool properly and of course the cosmetics of the board. If there is any moisture content I may use some 100% ethanol to bind to the water and pull it out of the cracks and tight areas before I use the compressed air and brush. For the board that you show I suspect that air and brush will work well.

John

Blowing with compressed air, believe it or not, can cause static build-up.  We used to use CFCs for this, but ozone and all.  Any idea what the shmutz is?  Water is an excellent solvent, although its low molecular weight gives it a great ability to penetrate.

Many PCB manufacturers use a final wash in TCE because it leaves the surface hydroscopic, I find that stuff to be really nasty, though.

In the past I have seen people remove all batteries and power before immersing the board in water and carefully washing away the dirt. Just make sure to thoroughly dry it out for a few days before trying to reconnect power.

Another trick I learned, is to remove all power from the board and pressure wash it in a filtered recirculating sink with of all things windex window spray. Then to blow dry it with warm air. I learned this trick from a guy that I take my monitors too for repair. He showed me the sink system he made up for this purpose. He says it works well and leaves no residue on the boards.

If you wash with water and need a quick-dry, sometimes a little acetone*. . .

*Test, research first, some things are dissolved in acetone. 

If you have access to proper PCB cleaning products, then use them.

I tend to use isopropyl alcohol or failing that methylated spirits.

A simple (old) toothbrush can help move anything that is stubborn, and then stand the board up on its edge to let gravity do the work for you.

Be aware that there will be fumes, and vapours given off by the product.

Mark

Thanks for all the tips.

FYI this is a main board from a Printronix P7215

@Clem Martins - The board powers up but gives memory errors, but the memort tests OK in the other printer we have.  So i thought it might be just the crap built up on it that's making it fail, so wanted to clean it before spening £2K on a new one.