Cleaning a PCB

[bigone5500]

I have acquired a bluray player and the pcb is dirty with bug stuff. I have also some cfc free electro contact cleaner made by LPS. Here it is: http://www.lpslabs.com/product-details/580

Will this stuff work well enough to clean the board? The player works but I want it to be clean.

 

[Arouse1973]

Yes this is fine for PCBs. But make sure you dont spray it on plastics, it may damage the surface. Dont use too much, just enough to clean the PCB. Use an antistatic tooth brush if you have one to loosen any dirt.
Adam

 

[bigone5500]

Thanks.

 

[hevans1944]

I generally prefer plain old isopropyl alcohol, anhydrous if I can get it, but 91% is commonly available at drugstores such as Walgreen's. Don't use "rubbing" alcohol as it contains too much water. The alcohol is usually much cheaper than commercial "contact cleaning" products and leaves no residue. Avoid using on plastics because the alcohol may affect them. I use a previously unused, clean, "acid brush" to scrub the PCB with alcohol, generously flooding the board and allowing the excess to drip onto a paper towel. So-called "acid brushes" consist of a short length of brush fibers secured to a rolled metal handle. I usually clip the fibers with a pair of scissors to make them shorter and stiffer. An "antistatic tooth brush" would also work, but I have no idea where you would procure such a thing. Allow the PCB to thoroughly dry before applying power, perhaps gently heating it with a hand-held hair dryer to speed the drying process.

 

[Arouse1973]

I generally prefer plain old isopropyl alcohol, anhydrous if I can get it, but 91% is commonly available at drugstores such as Walgreen's. Don't use "rubbing" alcohol as it contains too much water. The alcohol is usually much cheaper than commercial "contact cleaning" products and leaves no residue. Avoid using on plastics because the alcohol may affect them. I use a previously unused, clean, "acid brush" to scrub the PCB with alcohol, generously flooding the board and allowing the excess to drip onto a paper towel. So-called "acid brushes" consist of a short length of brush fibers secured to a rolled metal handle. I usually clip the fibers with a pair of scissors to make them shorter and stiffer. An "antistatic tooth brush" would also work, but I have no idea where you would procure such a thing. Allow the PCB to thoroughly dry before applying power, perhaps gently heating it with a hand-held hair dryer to speed the drying process.

Again a good reply Hop. Here you go.
http://www.ebay.co.uk/itm/like/1713...3=1&ff11=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108
Adam

 

[hevans1944]

Again a good reply Hop. Here you go.
http://www.ebay.co.uk/itm/like/1713...3=1&ff11=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108
Adam

Wow! Thanks, Adam. They sell these here in the States through Amazon too. Just need to find the right Google search string, which your link provided.

 

[bigone5500]

I wondered about alcohol. Now that I know this, I can use the bottle I have and get some acid brushes to clean my PCBs.However, I have some cleaning brushes that have a wooden handle and black nylon bristles. I wonder if they would be ok to use on circuits.

Thanks guys.

 

[hevans1944]

I wondered about alcohol. Now that I know this, I can use the bottle I have and get some acid brushes to clean my PCBs.However, I have some cleaning brushes that have a wooden handle and black nylon bristles. I wonder if they would be ok to use on circuits.

Thanks guys.

You should always be careful to avoid static discharge when working with circuit boards that have static-sensitive components, such as CMOS, installed. That generally means a conductive anti-static mat connected to an earth ground (green-wire ground in the U.S.A.) to place your circuit board on, a conductive wrist-strap with a one megohm series resistor (so as not to accidentally electrocute you!) attached to your wrist, and no sources of electrostatic potential nearby. No cats or dogs. Relatively high humidity is desirable as this will help to dissipate static charges before they get a chance to zap something. Low humidity can be a real problem on a cold winter day. Avoid wearing static-producing clothing such as nylon or silk. Consider increasing humidity by placing a tea kettle filled with tap water on a nearby hotplate. Here at home we have a gas-fired gravity furnace that dries the air pretty well, so we keep a full tea kettle on a back burner of the stove, adjusting the flame as low as it will go, to provide some additional humidity. Seems to work pretty well as long as someone remembers to refill the tea kettle every two or three days.

Make sure your isopropyl alcohol is at least 91% alcohol... the kind used to swab skin for disinfection purposes just prior to a needle injection (of insulin for example). The typically 80% rubbing alcohol doesn't work very well and takes a long time to dry because of the 20% water content.

I know nothing about wooden-handled brushes with nylon bristles. That's why I always use a horse-hair bristled acid brush with a metal handle: I know it won't cause me any problems. I don't always follow proper anti-static grounding procedures either, but it is better to be safer than sorry. Work at your own risk around static-sensitive electronics.

 

[chopnhack]

Yikes! Look at the size of this one - 2.8"x1.3" that is one large PCB. We use this for cleaning tub and showers!!

 

[brevor]

I have acquired a bluray player and the pcb is dirty with bug stuff.

If by "bug stuff" you mean roach droppings I would not clean it, I would incinerate it.

 

[Arouse1973]

Yikes! Look at the size of this one - 2.8"x1.3" that is one large PCB. We use this for cleaning tub and showers!!

Or big PCBs
Ads

 

[chopnhack]

Or big PCBs
Ads

True, I wasn't thinking of motherboards - that would benefit from such a huge scrubber Point of reference I guess, I haven't produced anything over 4x4

I have used denatured alcohol and acid brush with metal handle as well. It works pretty well, but the hairs are a little to flexible to get some stubborn flux off. The link provided has some really good solution if the bristles are stiffer.

 

[Arouse1973]

Can't beat a hugs scrubber

 

[hevans1944]

... but the hairs are a little to flexible to get some stubborn flux off. ...

Which is why I trim them shorter with a pair of scissors. And sometimes I wrap a few turns of tinned solid copper wire around the base of the bristles, pulling it as tight as possible, and solder that to the tinned handle.

 

[Arouse1973]

Which is why I trim them shorter with a pair of scissors. And sometimes I wrap a few turns of tinned solid copper wire around the base of the bristles, pulling it as tight as possible, and solder that to the tinned handle.

That's a good idea Hop, never though of that!
Adam

 

[chopnhack]

Which is why I trim them shorter with a pair of scissors. And sometimes I wrap a few turns of tinned solid copper wire around the base of the bristles, pulling it as tight as possible, and solder that to the tinned handle.

Brilliant!!