What does a ultrasonic machine do?

[Elow]

What exactly does an ultrasonic tub do? Today i cleaned a trumpet and forgot to put the valves in, i thought no biggie and grabbed the valves and put them down in the basket. Little did i know how weird it feels to put your hand in the machine while it’s activated. My wrist hurt but it didn’t really hurt. It felt very weird. Anyone want to explain how it works, and why it makes you feel super weird?

[bassbone721]

Isn't an ultrasonic just really high energy sound or some other sort of waves that are transmitted through water to, with the help of some solution, dislodge junk and stuff? I guess it would be sending all that energy into your hand and wrist and there isn't a great way for your body to dissipate the energy which could explain some pain.

[timothy42b]

I thought it made bubbles.

Checks wiki:
https://en.wikipedia.org/wiki/Ultrasonic_cleaning

Yup, cavitation bubbles. Remembering from design classes, when a cavitation bubble collapses, it does so asymmetrically, shooting a jet of liquid from the opposite side towards (hopefully) the object or piston cylinder wall. The bubble is tiny but that jet can move pretty fast, it will erode metal from a propeller.

[BGuttman]

I've put my hand in an ultrasonic bath and found a "tingle" like you describe. Remember, there is the action of the ultrasonic waves that gives a "massage" to you flesh and the action of the chemistry that may give you a slight chemical burn (depending on what it is).

If I remember correctly there are ultrasound massage baths, and they do ultrasound images in doctors' offices as a diagnostic tool (I had one of my kidney a few weeks ago).

[timothy42b]

Bruce,
I don't think the sound wave itself does anything.

I think all of the cleaning occurs because the sound wave creates tiny bubbles which burst against the object, washing it with the solvent or soap.

[hornbuilder]

Timothy is correct. The ultrasonic sound waves create vacuum bubbles in the solution. The formation and collapse of those bubbles creates a scrubbing action, and anything in contact with the solution will be "scrubbed".

It is important to realise that ulyrasonics by themselves (ie, if you just have water in the machine) may not be terribly effective against stubborn contaminants. Use of the correct solution to remove the contaminant is essential for best results.

[hornbuilder]

PS. The tingling you feel when you submerge your hand in the ultrasonic machine is that same cavitation happening in your tissues. FYI

[Posaunus]

PS. The tingling you feel when you submerge your hand in the ultrasonic machine is that same cavitation happening in your tissues. FYI

In other words, probably not so good for the cells in your tissue getting cavitated.

[brassmedic]

Isn't ultrasound used by physical therapists to heal tissue, though?

[Kbiggs]

I had P/T a few years with ultrasound. IIRC, the therapist said that ultrasound for P/T does two things: it gently warms and relaxes tissue without causing inflammation; and it can help to “break up” scar tissue for some tissues. Again, that’s my memory from a few years ago...

[timothy42b]

I had P/T a few years with ultrasound. IIRC, the therapist said that ultrasound for P/T does two things: it gently warms and relaxes tissue without causing inflammation; and it can help to “break up” scar tissue for some tissues. Again, that’s my memory from a few years ago...

Wow! Well, PTs may not know the science in detail, and it may work fine.

But it would make me wonder how something so gentle it can warm and relax delicate tissue can also destroy much tougher scar tissue.

[BGuttman]

The ultrasonic massage warms you through the cavitation of water in your cells.

My original intent was to assure Elow that his quick dunk in the ultrasound was probably not fatal.

Still, I wouldn't make a habit of it.

[Kbiggs]

The ultrasonic massage warms you through the cavitation of water in your cells.

Thank you for the concise and accurate description, Bruce.

[Doug Elliott]

"Ultrasound" covers a lot of frequency range. I would guess the 44K (I think) used for cleaning is not the same as used for therapy.

[DonH]

https://www.painscience.com/articles/ultrasound.php

[timothy42b]

Good point, I hadn't thought of that. Googling:

Frequency range for cleaning, 20 - 50 kHz.

For therapy, 1 - 3 MHz, for imaging 2 - 15 MHz.

[Crazy4Tbone86]

All of you will love this. I have a teacher friend who prides himself as being the ultimate do-it-yourself guy.

Our school district (large county district with over 40,000 students) is trying to develop a plan for sanitizing several hundred school-owned instruments that were turned in about a month ago (during the Covid-19 pandemic) for inventory, cleaning and maintenance.

My buddy was convinced that he could make an ultrasonic cleaner in his garage and save the county thousands of dollars. He constructed it using a giant galvanized tub, water with Dawn detergent in it and a random orbital sander. He tested it on his own brass instruments and was frustrated that it did not remove any calcium/lime scale. When someone pointed out to him that an orbital sander only produces 10-12 khz and most ultrasonic cleaners operated at 40 khz, he felt very defeated. Apparently, he has emptied the tub, turned it upside down and recreated one of those vibrating football games from the 1970s!

[harrisonreed]

I wanted it to be something like "I put my hand into the ultrasonic machine and now I have super powers" or "I put my hand into the ultrasonic machine and now I have billions of microfractures in every bone in my hand"

[hornbuilder]

As I mentioned above, you need to use the correct solution to get the best results. Detergent won't do much at all on limescale. Now, if he had an acidic solution in the tank, he would have had "some" more luck.

Realizing there are several different compounds that need to be cleaned out from inside horns, there are several solutions needed as well. There is also an essential order in which these compounds need to be addressed for best results as well. Knowing this, and utilizing this knowledge is why some of us can use the term " Professional" in our job title before "Instrument Repairer"

M

[Elow]

"I put my hand into the ultrasonic machine and now I have billions of microfractures in every bone in my hand”

It sure felt like that

[Doug Elliott]

...Knowing this, and utilizing this knowledge is why some of us can use the term " Professional" in our job title before "Instrument Repairer"

M

And knowing not to put your hand in it

[Posaunus]

If you really want to effectively clean instrument parts in an ultrasonic bath, I expect that you will need:
• A powerful high-frequency (> 50kHz?) ultrasonic generator;
• Appropriate cleaning solutions (perhaps more than one, but at least one bath should probably be acidic to remove alkaline scale);
• Knowledge of how much time to apply the ultrasound in each bath;
• Training or experience in the process(es);
• Enough smarts to not put your hand in the bath!

[timothy42b]

Here's an interesting article.

I vaguely remembered from engineering classes reasons to minimize cavitation, having to do with avoiding erosion of machine parts like propellers, pistons, etc. Cavitation produces bubbles by lowering pressure, that's why underwater video shows streams of bubbles behind the tips of a boat propeller. Those bubbles collapse and a micro jet from one side of the bubble shoots through the space and impacts anything close. Per this article that jet can be traveling upwards of 5,000 meters per second.

https://www.intechopen.com/books/cavita ... ll-under-a

And this one on medical ultrasound has some good photos:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4549845/

I did not realize that lithotripsy (I suffer from periodic kidney stones) uses the cavitation bubble effect to break the stone.

and here's an article with simpler explanation:
http://blog.sonomechanics.com/blog/acou ... processing

Which mentions that the temperature of that microjet can be 5000 degrees C.

It suggests to me that ultrasonic cleaning powerful enough to dislodge lime is probably going to punch a hole through the brass too, if you leave it in too long, or your hand bones, which are essentially similar to lime.

[harrisonreed]

5000C ??? I guess individual atoms within any substance can potentially be that temperature for an infinitely short period of time, our much colder. The jet must be extremely small and short lived

[timothy42b]

Check out this photo of a steel propeller blade:
https://www.google.com/search?q=cavitat ... 1tl5ZRpKIM

now imagine your soft thin brass tube subjected to something like that.

[hornbuilder]

The bubble size we're talking about here is microscopic. You can't see them with the naked eye (or with something like an optivisor) There is no possible harm to a brass instrument in using ultrasonic cleaners. (Unless there is already a bad case of dezincification. Then it is a toss up) Ultrasonics are used on the finest jewelry, on materials that are often softer than brass, on items much more valuable than a trombone!

[brassmedic]

But it would make me wonder how something so gentle it can warm and relax delicate tissue can also destroy much tougher scar tissue.

I have always heard scar tissue is weaker than normal tissue, not stronger. Massage is another way that scar tissue is supposedly broken up. I would assume it's not destroying desirable tissue at a greater rate than the scar tissue, or they wouldn't do it.

[bass]

on items much more valuable than a trombone!

Impossible, no such thing exists!

[timothy42b]

Here's a quote from a tech at Osmun:

As a degreaser it is invaluable in getting buffing compound out of nooks and crannies. When preparing for refinishing with lacquer or plating ultrasonic cleaning provides excellent results. It is most effective when the bath is heated which can cause some lacquered finishes to cloud or peal. Though running at room temp reduces failure of lacquer, it also reduces effectiveness of the solution.

In addition to loosening lacquer it will also remove plating that has lost it's bond. If there is any weakness in the plating it will blister and peal. And if there is "red rot" (dezincification of the brass alloy) the ultrasonic pulse will blow holes right through the weakest part of the spot. This is where skills in forming custom patches or replacing rotted parts comes in handy.

Sounds like this should be used by a pro.

Some advertising copy but with photos, by someone who wants you to buy their ultrasonic machine:

http://www.zenith-ultrasonics.com/ultrasonic_damage.htm

Of course, if we are scrupulous about not eating while playing, keep our horns clean, maybe we don't need to risk it very often.

[Doug Elliott]

I'm assuming it's only the bell that peals.

[timothy42b]

I'm assuming it's only the bell that peals.

Groan!

I noticed that when I posted it, but the typo was in the original, and I decided to leave it.

Now I'm glad I did.

[Kbiggs]

...Knowing this, and utilizing this knowledge is why some of us can use the term " Professional" in our job title before "Instrument Repairer"

M

And knowing not to put your hand in it

I would never have thought that education, training and experience would be desirable, let alone necessary, to avoid damage or injury.

[brassmedic]

Hot, or even sometimes warm, water just by itself can remove lacquer too.