Hi all, I recently purchased and ultrasonic cleaner. Even
though I am mostly pleased with it, there is a problem which has
baffled me. After taking out highly polished silver items. I find
very fine scratches on the surface. I have to replosh and try
again. Usually I leave work in for about ten minutes in warm water.
Does anyone have any ideas why this should happen and what I can do
about it. Richard
Richard, If the lines are not straight then it could be the sonic
etching the surface. This happens if the item is left in for a long
Even on the most aggressive sonics it would take more than an hour
at high temperatures. Different cleaning solutions can slow this
down or speed it up. If the solution is cold you could run it for
6-8 hours before this happens.
Several years ago while I worked at Rio a company named Brassler who
makes burs had them make anodized aluminum bur blocks mainly for the
Dental industry. I had to test them in ultrasonics to determine how
long it takes to start etching the surface at different temperatures
and different solutions and with different makes of sonics.
All the brands we tested will etch through the anodizing at elevated
Some other possibilities aRe:
Don’t place anything on the bottom of the tank. Suspend everything
Don’t place several items in a jar, beaker, tray together where they
can vibrate against each other.
Your solution has too much ammonia in it. High concentrations of
ammonia in the sonic tank will turn to acid when the sonic is
running. If you are using an ammoniated solution try one without the
Maybe the item had the scratches on it to begin with an were hidden
by the polishing compound.
For more on the proper way to use an ultrasonic go to our web site
at www.mpgrepair.com and follow the link ‘tech notes’ which is about
half way down the page.
If I can be of any further help email or call.