Re: Flux Removal - Blech! and Good Grief
- Be careful with some aggressive solvents, such as Carb or Brake cleaners,
We had a "bad" experience at work some years ago, where a customer with
some smoke damaged equipment (a fire in another part of their building)
had it "profesionaly cleaned", by people well experienced in such
Oddly, a short while (a few weeks) after the cleaning, all the OpAmp IC's
from one manufacturer (well known to us all, but I'm not going to say
Long story very shortened...
It seems the cleaning agent that was used (a common, but mildly agressive
de-greaser) difused through the chip packageing, and contaminated the die
and bond wires inside.
Replacing all the chips (1448 dual OpAmps, 100's of them!) was the only
way to fix things.
The upshot of that is in our context is, use water soluable or "no clean"
If you *Have* to use solvents, use as others have said, I.P.A. Or even
"Methalated Spirits" to remove flux. Both evaporate readily with minimal
hazard risk (except Fire!) If using Meth's, the remaining dusty film can
be removed with a damp (water) cotton bud.
As to dishwashers. I've cleaned small engine parts, and some ceramic RF
Power Tubes in them in the past. They come up lovely! :-)
- On Thu, 2011-03-31 at 13:10 +0100, Leon Heller wrote:
> On 31/03/2011 01:40, Bernie Hunt wrote:The problem wit the dishwasher is it does not get the water hot enough.
> > I've always been a fan of water soluble flux. I know some people don't like it, but I've never had a problem with it. Give the board a good scrub under hot water and it's squeaky clean.
> Some years ago I had a job interview with a company. After the interview
> they showed me round their facility which included a PCB assembly area.
> I noticed a dishwasher and asked them about it - they used it for
> removing the water-soluble flux from their boards.
They recommend using 180 degree F water for washing boards in a washer.
And the really good places use deionized water also for cleaning.
I really like water-soluble flux it works so much better than no-clean
or rosin core. But NEVER use it on wires. It wicks up the insulation
and 6 weeks later has eaten through the wire and no more connection
under the insulation.