Best contact cleaner for corrosion on pcb boards?

[artvandalai]

Whats the best contact cleaner for heavy corrosion, oxidation, rust on electrical components, pcb boards, and plastic? Deoxit d100 spray vs crc 2-26 or another product?

[marhuum]

Acid
Depends on the rust badness level the worse it is the stronger the acid should be used

consult chemistry sites, just brief;

HCl              strong

Citric Acid   mild

Acetic Acid   weak


On very strong eg. HCl ~33% it absolutely must be diluted with water by way of some water in a holder added/dripped little by little with some HCl

So let's we have 29%-30% HCl for ugly rust, the way is to put it in a small bottle.
As one hand hold cotton bud dripped, damped from that, the other hold a clothe damped with IPA mixed with some water, so as starting to clean up do it rather precisely only the rusted part wiping/rubbing it with the acid in a hand, then wait seconds, if it wets the non-rusted part, immediately wipe it with the other (prepared IPA) then at last thoroughly wipe, clean all the Acid-reacted part altogether with the IPA

On better rusted part just do first part, no need to hury wiping it with IPA then at last thoroughly wipe, clean all the Acid-reacted part altogether with the IPA

[themadhippy]

for something a bit gentler bicarb cream.

[Ian.M]

Acid
Depends on the rust badness level the worse it is the stronger the acid should be used

consult chemistry sites, just brief;

HCl              strong

Citric Acid   mild

Acetic Acid   weak


On very strong eg. HCl ~33% it absolutely must be diluted with water by way of some water in a holder added/dripped little by little with some HCl

So let's we have 29%-30% HCl for ugly rust, the way is to put it in a small bottle.
As one hand hold cotton bud dripped, damped from that, the other hold a clothe damped with IPA mixed with some water, so as starting to clean up do it rather precisely only the rusted part wiping/rubbing it with the acid in a hand, then wait seconds, if it wets the non-rusted part, immediately wipe it with the other (prepared IPA) then at last thoroughly wipe, clean all the Acid-reacted part altogether with the IPA

On better rusted part just do first part, no need to hury wiping it with IPA then at last thoroughly wipe, clean all the Acid-reacted part altogether with the IPA

Anyone who thinks adding Chloride corrosion to your PCB's problems is a *GOOD* idea shouldn't be trusted with anything more delicate than a pick-axe!  It will eat the copper tracks and slowly keep on going even after you *think* you have neutralised it.  See https://en.wikipedia.org/wiki/Bronze_disease

Phosphoric acid is suitable for rust treatment - it converts rust into insoluble iron phosphate and leaves a protective iron phosphate layer on the surface of the iron or steel.  Topically applied, its OK for screening cans and mechanical parts.  However if the rust is on tin plated iron component leads, they are probably already unsalvageable as the rust tends to get under the tin plate leaving whatever iron remains in an extremely fragile state and probably compromising the component's end caps and the solder joint to the pad.

[Haenk]

It all depends; best is to show a picture of your issue, so the forum could decide - different materials require different procedures. A rusted amboss will require some mechanical work with your angle grinder, while a scratching potentiometer will be pretty unhappy with that method.

[Bud]

Try soaking in WD40 first. May take a few hrs. This is what a prominent youtuber does who restores old computer motherboards.

[factory]

Don't know about you, but I want to keep WD40 well any from anything electronic I value, it used to be the weapon of choice for writing off VCRs (along with cats). Probably don't want that crappy residue on any precision equipment either.

David

[marhuum]

just AI;

Bronze disease generally requires ongoing, prolonged exposure to chlorides and moisture to initiate and sustain the corrosive process, which means brief contact (like accidental exposure on a PCB followed by immediate cleaning) is unlikely to cause it. The reaction that drives bronze disease relies on the presence of chloride ions and moisture for an extended period to form copper(I) chloride, which then reacts with oxygen and water, creating a self-perpetuating cycle of corrosion.

If you immediately clean the surface with IPA or another effective solvent, you're likely removing the chloride residues before they can start the cycle. For bronze or copper alloys to develop true bronze disease, the environment must maintain a high enough chloride concentration for some time, so prompt cleaning and drying should prevent any such deterioration on a PCB

[timeandfrequency]

Hello artvandalai,

In case of rust (dark red / iron corrosion), if you want to remove it when it soaked into another matter, you may use oxalic acid (dilute 1:1 weight in boiling tap water). If you need a creamy/sticky consistance, add gelatin or agar-agar. Cover with food wrap (cling film) to avoid evaporation.

If you want to stop the corrosion on an iron part, use phosphoric acid (70 %) as Ian.M stated above : the rust will be converted into a dark gray surface. Do not rinse/clean with water, just dry the part.


For strong contact cleaning/desoxydation on switches and relays, I recommend Kontakt 60.
Do not keep it on the surface to be cleaned for more than a few hours because it will eat up all of the copper parts. It needs to be neutralized with diethyl ether or Kontakt WL.

[tooki]

For strong contact cleaning/desoxydation on switches and relays, I recommend Kontakt 60.
Do not keep it on the surface to be cleaned for more than a few hours because it will eat up all of the copper parts. It needs to be neutralized with diethyl ether or Kontakt WL.

…and then followed by Kontakt 61 or other protective oil or grease.

[nctnico]

Whats the best contact cleaner for heavy corrosion, oxidation, rust on electrical components, pcb boards, and plastic? Deoxit d100 spray vs crc 2-26 or another product?

A product sold in the US under the name 'Simple green'. Takes care of dirt and grease. Followed by a rinse of some form of alcohol (but test plastic before applying on large surfaces). Switches / contacts need to be replaced. Once oxidized, these are fubar as the contact plating is gone like time.