Cleaning Up Your PCB

I use flux for all my soldering. It tends to leave a yellow residue I am sure most people who have soldered something are familiar with. So I found an easy, and cheap, way to clean up my solder areas while I am working.

You will need an acid brush (the cheap type with the tin handle), a liquid dispenser like a pump bottle or wash bottle, a solvent, and some type of paper wipe. See the photos to see what the brush and the bottles look like.

I like to use 90% (or higher) isopropyl alcohol for cleaning. It doesn't cost much, evaporates quickly, and has a lot less chemicals in it than most other PCB cleaners. Check to make sure the isopropyl alcohol will not harm anything you're working with. I haven't found anything I have soldered yet which it has had any sort of detrimental effect on. USE LATEX GLOVES AND GOGGLES WHEN USING ISOPROPYL ALCOHOL. ONLY USE ISOPROPYL ALCOHOL IN A WELL VENTILATED AREA.

Kimberly-Clark Kimwipes work well as a paper wipe but I find single ply, hard and "scratchy", no-name brand toilet paper does the job just as well. Don't use Charmin or some soft and fluffy brand as it will leave fibers/lint on your PCB.

Cut the acid brush so you have an angle on the bristles. The short side is for scrubbing, the long side is to get into hard to reach places. Dip the brush in the isopropyl alcohol, or wet the area with the wash bottle, and scrub the flux residue, or whatever else you need removed, off. Wipe with a paper wipe to get the majority of the solvent off. If you're using isopropyl alcohol, the rest will evaporate.

Comments

[TaranA3]

will non latex gloves work as i'm allergic to latex and what brand of solvent did you use, does it come in a 100-200ml bottle?

[Overlord_Laharl]

i get my Isopropyl Alcohol from Walgreens as they commonly have a 32 oz bottle of 91% for less then $4, many times on sale (right now its on a a buy 1 get 1 half off)

i just put a spray top on it (i have a bunch of brand new tops (meaning unused, not reclaimed (because many plastics will absorb a little solvent). i cant remember where i got them from, its been years.)
spray it on the board where i need it, and brush away

i also use this bottle of alcohol to turn toilet paper into alcohol pads, and to clean around the House, works well on many adhesives and sharpie markers. to steralize food prep area before beginning vacuum sealing food.

no spray lids? then a Zep 32 oz bottle is a wonderful thing. home depot, menards, and lowes sells these for under $4 each, and the sprayers are NICE. (the HD brand used to be even better cause it has wide mouth by design and the exact same sprayer, but the last time i bought some, the sprayer was cheeped out on.)

[profpat]

nice one,


btw, i use lighter fluid, denatured alcohol and acetone..

[Overlord_Laharl]

as others have said be careful with acetone, it will break down ABS.
more importantly if your using a professional PCB (like from OSH park) then it can damage the solder mask as it breaks down epoxy (and solder mask is epoxy most of the time)

[LynxSys]

I advise against using acetone. It will damage any plastic components it touches if you don't rinse it off, which adds a bunch of steps. A single step using isopropyl alcohol works just fine, especially if you can get the less dilute stuff.

[AdamS323]

I use Methanol (Methyl Hydrate) instead of Denatured Alcohol (it's actually whats used to denature ethanol). I avoid Lighter Fluid completely as it really only is useful for dissolving sticky residue (which Goo Gone does much better, and safer). and acetone is to be avoided, like all ketone solvents. useful for etching though.

[Dave-T]

Pat,

Thanks. I use denatured alcohol too, though I find the isopropyl alcohol is easier to get because I have a pharmacy just down the road. I haven't used lighter fluid - I would think it might leave some residue. Have you found that it does? I am selective about what I put acetone on as it is quite strong and I have melted plastic with it before.

[codebeat]

Toothbrush + 96% alcohol = great stuff. You can also use an old T-shirt to wipe off dust and other 'raw' dirt. Don't use paper, it is too weak.

[Chief51]

When cleaning up flux on a PCB with Isopropyl alcohol if as a final step you lay a Kimwipe or your toilet paper over the area you're cleaning and brush the alcohol through the wipe onto the board the flux residue will float onto the wipe. Then I use a dry wipe to mop up any wet spots Leaving the board dry and the sticky flux gone with less use of materials. I like your tip about the "scratchy" TP and will try it Thanks!

[Chief51]

Actually, maybe float onto the wipe is the wrong terminology. The surface tension pulls the flux residue onto the wipe as the wipe is withdrawn.

[keesv1]

Yes isopropanol, but it makes your polyester compound soft. lotlack for protection is really a hell to get it off if i need to replace a component or repair a pcb, i try to get it off with spotclean(isopropanol in pen format).... just like teslanol. Dries fast but i wouldn't recommened it.

Aceton i saw on youtube, with a men which repaired a amiga 500 with acid over it. Cleaned well.

gr richard

[utest_mal]

Nice one

[pfred2]

I trim my flux brushes too. The bristles are too flexible the stock length. I trim my brushes a little shallower an angle than you do, but leave mine a bit longer on the short side. I have a pump bottle kicking around someplace. Perhaps even two of them. At home I use spray flux remover. I still brush it though.

[Dave-T]

Pfred, I'm not a fan of most spray flux removers as they have a lot of harsh chemicals in them. I find rubbing alcohol works really well for what I have needed to do so far.

[jamesrojas71]

I have found some good cleaning instrument for cleaning of PCB at http://www.atekllc.com/pcb-cleaning.shtml. I haven't purchase them yet but I think it might be good one.

[Dave-T]

James, the equipment that A-Tek Systems sell will definitely clean what you need cleaned but you're talking about spending tens, maybe hundreds, of thousands of dollars for that equipment. This Instructable is aimed at the home hobbyist/DIYer who is not necessarily in "production" mode and/or doesn't have a ton of cash to spend.

[canucksgirl]

Good, useful info Dave-T. :-)

[Dave-T]

Thanks.