Most importantly.

Does anyone know how to make an ultrasonic cleaner?
Is it just vibration, or does the vibrating motor need to be tuned to a specific frequency.

If I use an old hand drill with a concentric hub on it, and a variable speed power supply, can I get it to the correct frequency?

If I can, how will I know I am at the correct frequency?

Rich

Frequency where will be nowhere near ultrasonic frequencies. Look on ebay, not sure if u can use one designed for jewelry for your needs. TRying to clean a PCB for an engine management system? Search ebay for "ultrasonic cleaner". Some stuff goes for $40. not sure what u need...

bigger for autoparts.

So, what frequency is needed?
http://en.wikipedia.org/wiki/Ultrasonic_cleaning
Gotta love the internet.
Rich

Ultrasonic means "beyond sound" and for a cleaner, frequency is rarely discussed.

Make an ultrasonic device? Yes I have. If Ya wanna cut and cauterize tissue, 55 khz is the magic frequency number. It involved a whole lotta math, transducers, precise mechanical components, vibrational analysis of resonant systems, fricking exacting tuning, and a whole lot more.

I've seen a lotta small cleaners for rings and ink pen tips but not a lot for bigger stuff. It can take a ton of power for larger systems to shake that much mass and the surgical ultrasonics use a load sensitive generator that dumps in more power as the load goes up.

As per the little flashes of light that sometimes occur in liquids, some think they may be fusion power......

Ken

I made one (or close to one) out of a small Tupperware container that was hose clamped to the tip of an engraver. Works great on injectors.

There was a thread, very old, first year of the site.

Definitely need to have a good friend with one of these. Good for clogged up carbs

Ultrasonic cleaners work amazingly well. We have two were I work. One has simple green in it and the other has a mix of water and citric acid. A good one is not cheap the ones we have were about $1700 a piece. Worth every penny though!

From what I have been reading, the lower the Mhz, the larger the cavitation bubbles...so it removes larger deposits ofr crud. Higher frequency does a better job of cleaning small delicate parts with smaller bubbles that are closer together..
I got the basic principles.

Now, I want to build a cleaner like Mark Henry did, but large enough for a motor, or larger parts...I want to use a motor that I can find...not a $1500 sealed special motor....blah blah.. So, help me out here. How would I determine the frequency of a motor...

Here is what I have and what I want.
I have a few large stainless steel sinks, free standing (previously used to wash large dogs...) I have loads of motors.

From my simple mind, here is the idea.
Take a motor and mount it to the outside, like Mark Henry did with his little cleaner. On the shaft of the motor I will attach a metal pulley made from solid aluminum. This pulley will be drilled on the edge to allow me to add bolts on the outer edge to tune the vibration. I have a variable speed system that I use on my router table that allows me to run the motor as slow as I want, and as fast at the motor will go, its a dial/POT in a box.

How would I measure the frequency, or even better, is there some math formula (that I can understand) that will tell me at speed X you produce Y frequency.

If you look at the limited information online and at the manufactering web sites of these cleaners you will notice that none of the ultrasonic cleaning companies tell you what frequency they are running at.
This LACK of information makes me believe deep down that this is really simple and the capitalist market is just hiding the information so they can sell $3500 sinks with elec motors attached to make them bubble.

So, take the sink, pick a motor, no heat, and lets figure this out.
I have an electronic eraser that I will try first, similar to an engraver, it vibrates at high speed. I have motors that range all the way up to 20,000 rpm's.

Rich

My guess would be you are looking for the resonant frequency of the motor to best clean. I'm not exactly sure how you would find it for something that big. One of the reasons the little jewelry ultrasonic cleaners work is that with such a small, simple part, its more likely a larger Hz band would clean it well. An engine block could be tougher, but I see no reason with time enough adjustments it could be done.

good luck rich

And the world of ultrasonics begins at the point where you can't hear it anymore- at about 20,000 -22,000 hz. A hertz is vibrations per second.

A motor rotates at RPM's or rotations per MINUTE.

So an arm on your 20,000 rpm motor is going to repeatedly make a splash at...

20,000/60 = 333 hz........ or 333 vibrations per second. That's above "base" notes on yer stereo (20-60 hz) but far far away away from ultrasonic.

Maybe ya want a cheap sonic (333 hz) vibrating tank.

Or a monster stereo system tuned to the highest frequencies to hit the very bottom notes in the ultrasonic realm.

Ken

My little cleaner was likely not in the ultrasonic range, but it did do a good job cleaning injectors. One thing I found is if I put too much cleaner in the cup the action would get weaker and splash all over. With just enough to cover an injector it made little wavelets (sp?) on the surface and cleaned better.

What you propose will work, but like mine not ultrasonic and I can tell you it was not quiet. Had to put it behind my shop because the noise drove me crazy and it takes all day to do just one injector.

I can (maybe I can't) imagine what a racket something that large would make...

Which is why ultrasonics can be good- no sounds that we can hear.

hm, I'm not so sure. My mom has an ultrasonic jewelry cleaner and while I'm sure you can't hear the actual cleaning frequencies, you can still hear a hum from the motor (maybe? not terribly loud, just annoying) or something... I would only imagine it would get louder the bigger the cleaner gets.

We have a few different types of ultrasonic cleaners at work that we clean pieces of our spray equipment ex: mini-bells, shaping air plates,etc. I will bring the manual on one of them home and add any information I can to this thread. I'm thinking that they have some kind of speaker in them that fires and drives the bottom of the tub. These are really nice as they have heat with them as well. They work great on removing waterborne paint but not worth a damn on solventborne. The manufacturer recommmends not using flammable liquids so that puts a limit on cleaning.

Ok then,
Hmmm
Can I make ultrasonic sound with a hacked stereo system???

Or an old ham radio?

Rich

Transducers work well. Most are ceramic or crystalline but there is a plastic -Polyvinylidene Fluoride, that can be used. The subs use PVDF for the sonars.

Yer getting the picture... big assed power amp, frequency generator tuned to apply the power at the right frequency, and a vibrational generator to convert the power to ultrasonic energy.

Ken