What is the best method for cleaning up leaked electrolyte? This PCB has some
corrosion on IC leads and vias.
Is there a corrosion neutralizer that would be effective? Since the potential
for corrosion in places that aren't accessible (deep in the vias), a liquid
that can neutralize corrosion is called for.
Would something like DeOxit work in such an application?
This is on a Tek scope acquisition board.
litmus test first to see of acidic or alkaline and go for the opposite as
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
If you can beg or borrow an ultrasonic cleaner, ordinary water with a dash
of washing up liquid will do fine,
Any crystals or ceramic resonaters should be removed before ultrasonic
If the construction of any components mean they trap water, a second dip
without detergent will be needed, and you may have to bake the board to dry
everything - the pre-heat phase on a SMD oven should do it.
I scrub with white vinegar and a toothbrush, then rinse with alcohol. If
the corrosion is more severe, mechanical methods may be needed,
Scotchbrite type cleaning pads work well but you have to be careful not
to damage fine traces. In some cases it's best to neutralize and then
clean off as much residue as possible and then leave the remaining
You can always do it while the wife is out, it's not gonna damage anything.
When I was a teenager I occasionally washed engine parts in the
dishwasher, not something I'd recommend, but my mom never found out.
["Followup-To:" header set to sci.electronics.design.]
John Larkin wrote:
Excellent advice. A household dishwasher (with the normal powder
detergent) is an extremely cheap and powerful cleaning device for almost
anything. It took me a while to convince my ex-lab to use one for
cleaning larger UHV parts rather than an appropriately-sized ultrasonic
tank which would have cost the equivalent of 100 dishwashers. There are
things that a dishwasher isn't good enough for, but they are few.
The electrolyte is mostly a weak organic acid. Neutralizing it with
any manner of mild base will prevent further corrosion. I use
household cleaner, such as 409. You can tell that it's working if the
liquid foams slightly on contact.
409 will also break up the copper sulfate. However, you'll have to
wash off the residue.
The trick is not neutralizing the electrolyte. It's cleaning up the
mess afterwards. I smear the residue and "suds" around with a paint
brush, wash with water and/or alcohol, and then use compressed air to
blow as much of the liquid away (so it will dry quicker). Canned air
doesn't work well. An air compressor and nozzle work just fine.
No. It will leave an oily residue that will eventually turn into a
big mess when the dust lands on the oil. It's also kinda expensive
for washing boards.
Obviously, there's no need to supply a Tek model number. Many such
pieces of test equipment are very sensitive to leakage caused by board
contamination. For such boards, you may need to give it an alcohol
bath, possibly several times.
Jeff Liebermann email@example.com
150 Felker St #D http://www.LearnByDestroying.com
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.