Using an ultrasonic

Hi - I’ve lucked into a used elderly ultrasonic by Grobet. Never
used one before. Any tips, do’s, don’ts anyone might be willing to
share would be most appreciated!

Will it remove tarnish from silver?

Beth Wicker
Three Cats and a Dog Design Studio

Beth, one suggestion is that if the ultrasonic does not heat the
cleaning solution, that you heat your solution before putting it in
the ultrasonic. I know that everyone has their favorite solution,
but mine is plain water and a hearty dose of 409. How Much? Well, I
sort of play it by ear. If I am not getting the results I want, I
just add some more 409. When finished cleaning, I pour it into a jar
to be reused. Alma

Beth, Congratulations on your new acquisition! The answer to your
question is “some” but not enough to to make the stuff ready for the

I use Tarn-X which you can find at your local Walgreens or Walmart
for about $6 to $9 a bottle. It still doesn’t do as food of a job as
polishing the piece but it is VERY effective at removing tarnish.

Keith Hible.

Will it remove tarnish from silver? 

Not effectively.

Don’t put your fingers in it while it’s running.

Now that I’ve said that, I know you want to.

Paf Dvorak

Alternative Ultrasonic juice

I know that everyone has their favorite solution, but mine is plain
water and a hearty dose of 409. 

I use ZEP commercial Heavy Duty Floor Stripper (PDF file)

It doesn’t damage anything that I can find so far.

I mix it fairly strong.

Paf Dvorak

Hi Beth

dishwashing liquid in water works for me.

Many use ammonia but I don’t like the stuff, smells.

Won’t remove tarnish. For that I use a JCR cleaning unit, will clean
a piece in less than 20 seconds.

And I mean clean. Gets the crap off gems as well and is safe for all
of them and I mean all of them even opals (solid) and soft stones
like turquoise. Have used mine for 3 years with great success.

It is a great sideline for customers, I charge $2 to clean a piece
of jewellery (if its full of crap then I charge $5). Two bucks for 20
seconds. Do the math!

here is the link to check it out

I am not affiliated with this company


JCR are made in Australia and don’t know if they are available in

Worth every cent, about $300.


Hello Beth,

Ultrasonic cleaning is good for removing oils and greases from
pieces but to remove tarnish (silver sulphide) I am afraid there are
only two options, chemical cleaning (e. g. silver dip solutions) or
elbow grease (re-polishing)!

I hope that the following about ultrasonic cleaning and
its limitations is of use to you.

Ultrasonic cleaning works by using a sound generator to create
cavities (bubbles) within a liquid in the cleaning tank. These
cavities collapse when they come into contact with the objects in
the tank that need cleaning and it is the jet these cavities create
when they collapse that cleans the part, this jet blasts any dirt
off the surface of the part. The cleaning solution that you add to
the water in the ultrasonic tank increases the effectiveness of the
cleaning operation by increasing the ability of the water to
dissolve and hold in solution the grease from the polishing
compound. Typically this cleaning solution (detergent) that you add
to to water should leave you with a solution that is neutral to
slightly alkaline (pH 7-9). For initial testing you will find that a
washing up liquid such as Joy will give acceptable results, just
don’t add too much detergent about a 1-2% solution by volume is more
than enough.

There is one major compromise in using ultrasonic cleaning systems
to clean off polishing greases. The best temperature range for
ultrasonic systems to work is 40-60C (104-140F). Above this
temperature the ability of the cavities to form drops off and the
cleaning ability of the tank is markedly reduced. Therefore it is
good practice to clean your pieces as soon as possible after
polishing. If you allow the polishing greases to harden in air
before cleaning then a higher temperatures of about 80C (176F) are
required to soften the greases and get them to dissolve into the hot
water with the cleaning solution added. Where people have allowed
the polishing grease to harden I recommend a separate pre-cleaning
soak in very hot water and then the ultrasonic clean as normal.

Finally don’t leave the pieces in the ultrasonics for too long,
especially when they are not being moved in the solution, continual
impact of the cavities on the same part of the piece can result in
the cavitation eroding the part being cleaned. This looks like
little white pin pricks on the surface of the polished piece. This
is particularly the case with parts with very highly polished,
smooth surfaces and the effect is more prevalent with a lower
frequency ultrasonic cleaning tank. So I would recommend 2 minutes
maximum cleaning time, then pull the pieces out, examine them to see
if they are clean and if not then repeat the cleaning process.

Charles Allenden

Keith- Tarnex= Bad. Check our Jeffrey Herman Silver Smithing and his
article on silver polishes. He explains why Tarnex is so bad.

Jo Haemer

The best tips on the use and care of ultrasonic cleaners that I have
seen is a pdf article by Ken Kotoski, who used to be a regular
Orchid contributor. He used to repair ultrasonics (doesn’t anymore),
so he was very familiar with all the brands and qualities. He gives
a great test that you can do periodically to see how well your
ultrasonic is working. I’m going to attach the article to my post in
hopes that Hanuman will have a way to make it available to you

Janet in Jerusalem

Thanks to everyone for the helpful responses, and a special thanks
to Andy “The Tool Guy” Kroungold from Stuller!

Beth Wicker
Three Cats and a Dog Design Studio

I love my ultrasonic, although I am on my second ultrasonic cleaner
as the part that produces the ultrasonic failed in the first one.

I use dish washing liquid and ammonium hydroxide (ammonia in water,
as ammonia is a gas), both mixed into water. I always forget how
nasty the "ammonia"is, always intending that the next time I mix it,
I’ll do it outside - but never remember! Perhaps I should write
myself a note on the bottle. I heat the solution to 50 degrees
Celsius and use with the ultrasonic for “hardy” stones, but for more
fragile stones such as opal, turquoise, emerald, tanzanite, etc, I
just use the heat of the solution, and brush the pieces with a
softnylon toothbrush. I have tried just using a heated solution of
dish washingsoap and water, but I’ve never yet managed to
effectively clean polishing compound off, without the “ammonia”.

My second machine came with a stainless steel basket, which I was
thrilled about, as the first one didn’t have a basket. However, I no
longer use it, asthe action of the ultrasonic moving the sterling
jewellery against the stainless steel was actually scratching the
silver, or at least making it frostyin appearance (but not in a nice
way), and this was after I had done the final polish! Do other
people use stainless steel baskets in their ultrasonics? I’m going
to have to rig up a similar method that I used with my first
machine, which was a couple of wires across the top, hooked over the
edge, withmy jewellery pieces suspended from “S” shaped sterling
hooks which hang offthe top wires and suspend the jewellery just
under the surface of the solution.

I could do with a gizmo for removing tarnish though, as I only work
in sterling silver.


Thank you, Janet, for the Kotoski ultrasonic Very
useful and I sure was doing some things wrong. Ruth Mary

On every ultrasonic I’ve owned, (literally 1/2 a dozen or more) the
instructions say not to use ammonia. In some cases it will actually
blow you warranty. Ammonia will eventually wreck your tanks.

Could the whitish pin prick marks also be due to jewelry pieces
rubbing against the surfaces of adjacent pieces in the tank?

Warmest regards

I’ve had an ultrasonic for almost 20 years now, from Gesswein. A
jeweler friend told me how much he likes Supra Galvex cleaning
solution, again from Gesswein, so that’s what I have been using.
Works pretty good, and after almost 10 years, still have a quarter
bottle left. Before that, I was using Gesswein Ultrasonic cleaning
solution, which again, works well, and I still have some of that
left. A tip - use champagne corks or corks that are bigger than a
wine bottle cork, screw in a brass hook into the cork and then the
cork floats in the ultrasonic with the jewelry hanging off the hooks.
I find it the best way. I never got a cleaning tray with my
ultrasonic, and I didn’t like hanging jewelry off thesides of
cleaner. I make my own brass hooks, so that I can have a hook I can
customize, before I screw them onto the corks.

If you need to get your torch tips clean, or even remove the flux
from your tripod screen, the ultrasonic will get them clean. I can
extend the life of both torch tips and screens. You may need to
change the solution once or twice, but it’s worth it.


Ammonia will eventually wreck your tanks. 

Not to mention the smell.

Paf Dvorak

Hello Kofi,

In my experience the white marks are nearly always due to the
ultrasonic cleaning action and have a distinctive comma-like shape
when viewed with an eyeglass or under a microscope.

If we get just a little bit more technical about the way ultrasonic
cleaning works; what you are doing is sending a high-frequency sound
through a cleaning liquid. In this liquid areas of compression and
rarefaction occur. When there is enough energy (i. e. sufficient
amplitude) being introduced into the cleaning liquid cavitation
occurs; cavitation is the formation of very small bubbles caused by
voids or tears being created in the cleaning liquid by the sound
waves. When these bubbles collapse or implode during compression,
the energy (pressure and localised temperature) associated with this
collapse is responsible for the cleaning power of ultrasonics. In
effect the collapse of the bubbles ‘blasts off’ any dirt or grease
on the surface of the piece you are cleaning.

The white marks occur when you leave the pieces in the ultrasonics
for a long period of time and a standing wave is set up. This means
that the bubbles are collapsing on the same point on your piece
every time and erode away that point of the surface. To prevent this
either gently move the pieces during the cleaning process or only
carry out the cleaning for short periods of time (2 minutes maximum)
remove and then re-clean if necessary as this prevent the standing
wave being set up.

Hope this explanation helps.
Charles Allenden

Before that, I was using Gesswein Ultrasonic cleaning solution,
which again, works well, and I still have some of that left. 

I like that solution too. What I particularly like about it is that
all of the polishing compound seems to settle out of it overnight.
So in the morning I can just pour off the clean solution, wipe out
the crud (for refining) and pour the clean solution back in. It seems
to last longer than other solutions I’ve used. It seems that some
solutions keep a good deal of the compound suspended in the solution
rather than allowing it to settle out.


On every ultrasonic I've owned, (literally 1/2 a dozen or more)
the instructions say not to use ammonia. In some cases it will
actually blow you warranty. Ammonia will eventually wreck your

Ammonia’s great for a lot of things—we don’t have household
ammonia here in Israel (!) and I really miss it. To use ammonia in
your ultrasonic, simply put household ammonia with a bit soap in a
beaker, and float the beaker in your ultrasonic cleaner…:-)…

Janet in Jerusalem

Hello Joy,

What a nifty idea - putting a hook into a cork and using that to
suspend jewelry in the 'sonic solution!!! Excellent. Certainly easier
and quicker than putting jewelry into a small ziploc plastic bag with
cleaning solution, and closing it with some air trapped inside. (I do
recommend this if you think there are small stones that will be
dislodged - the stones are contained in the little bag and you don’t
have to search the bottom of the 'sonic for them.)

My hint, which was garnered from a previous Orchid posting: I have a
suspended basket & use it to hold a glass lidded container that
contains the cleaning solution. The 'sonic is filled with plain
water to which a few drops of non-sudsing detergent has been added.

To protect the sides of the 'sonic from wear related to the basket,
I wrap a section of panty hose around the ‘ears’ of the basket where
it rests on the rim of the 'sonic. That way there is no
metal-to-metal contact and the basket stays put. It’s easy to change
cleaning solution when it gets dirty. Water needs to be added
periodically due to evaporation and is changed every few months.

Thanks everso! This is what I love about Orchid - the sharing of
inspired tricks of the trade. Kudos to Hanuman, Ton, and Charles L-B
for their inspired idea behind Orchid.

Judy in Kansas