I have started doing some pen plating using a 24k solution. The
elecro cleaner I purchased from Rio works just fine.
Unfortunately, I dropped and broke the entire container of electro
cleaner.
I hope you cleaned it up carefully. It’s a pretty caustic
solution…
My first question is... Is electo cleaning really necessary if I do
all of the other cleaning steps (ultra sonic, steam, and acid dip)?
Yes. Both ultrasonics and steam cleaners are useful for the larger
scale tasks of removing dirt, polishing compound, etc, and leave
things visually clean and bright. But both can leave surface films
that will interfere with good plating adhesion. The water in a steam
cleaner can build up impurities and even though the steam aught to
be pure water, some impurities can get carried over and leave
deposits on the metal. Likewise, some cleaning solutions you might
use in the ultrasonic can actually contain things like lanolin, so
they’re easier on the hands of the people using it. So those too can
leave a slight chemical film on the metal. The acid dip does not
actually “clean”. it’s task is to remove any surface oxidation, which
may be an invisible surface film on some metals, which also can
interfere with good adhesion of the plating. It removes any passive
oxide films, leaving a surface that is chemically receptive to the
plating. In a pinch, ordinary pickle solution works for this too.
Commonly, the acid dip is based on phosphoric acid, which is a bit
more effective, especially on alloys containing nickle, which
without it forms an invisible passive oxide. You can actually skip
the ultrasonic and steam if the item looks clean, but the acid dip is
important with some metals you might be plating on, and the
electroclean is important since, unlike the ultrasonic and steam,
it’s capable of leaving the surface chemically clean, not just
visually clean.
I noticed that the electo cleaner from Rio contains sodium
hydroxide (lye). My second question is... can I pick up some drain
cleaner at my local hardware store and use that?
If the local drain cleaner were also just lye, that would work. Some
drain cleaners are just lye. But others contain other agents, or even
no lye at all. And, then you don’t know the concentration, so you
might not get the electroclean mixed to an effective bath. Better, if
you don’t want to buy the commercial electroclean, to buy sodium
hydroxide (lye) as a chemical from a chemical supply house, and
follow a published recipe for electrocleaning solution, if you wish
to mix your own instead of buying the mix. That would give equal
results.
However, frankly, the commercial electrocleaning mixes are cheap.
What’s the problem with just buying more?
And next time, be more careful. None of the baths used in
electroplating are things you should be spilling on the floor. In
fact, of them all (depending on the type of gold plating solution
you’re using), the caustic lye solution may be one of the safer
ones…
Pen plating, by the way, while useful and interesting, is in my
experience, less forgiving of sloppy procedure. The small anode area
(in the pen), and restricted current path (the pen) means you really
have to be doing it right regarding cleaning, voltage, pen use, etc,
if you want the best results. Cut too many steps and you’ll find
plating that isn’t the right color, or that rubs off with a fingertip
instead of adhering properly to the metal. Immersion baths are
somewhat more forgiving, but still rely on proper cleaning before
hand. The electroclean step is perhaps the most important of those
processes. Not all metals really need the acid dip, but everything
benefits from the electrocleaning step.
Hope that helps.
Peter