The Most Underrated Tool? (DIY or Buy) Ultrasonic Cleaner!

Tip for cleaning small parts in ultrasonic cleaner: Add cleaning solution and parts in a small glass jar and put that jar in the cleaner filled with water. Easier to clean and no need to use so much cleaning solution. Especially handy, when some small parts require different cleaning solution than what is normally used.

I'm working in a company which uses ultrasonic baths a lot. Funny thing is, that the Aluminium Foil Tests are officially performed regularly to make sure every ultrasonic bath is working properly. It apparently is the best way to make sure everything is all right without the need of disassembling the machines all the time.

It's also worth mentioning that if you DIY, the basket is an essential part of the machine - they only do their job right if things do not sit directly on the bottom.

One of the big things to consider is that while it may be a bit faster to do it by hand, you can also do something else while it does the cleaning

Just to add something further to be cautious about: Do not clean MEMS-devices (accelerometers, gyrometers, microphones) in an ultrasonic cleaner, they will break. I think 'breaking taps' made a video explaining the matter further.

Love this series, but what I really love is that you made an effort to reverse engineer the board to see if it's something we can make ourselves. Really appreciate that kinda effort.

Before PCB washing always READ DATASHEET. Some parts like crystal oscillators can be damaged with ultrasonic cleaning.

The DIY solution will get interesting if you mount the transducers onto your steel kitchen sink. Big volume and you can clean your dishes by ultrasonic and release the waste water directly ;)

I've been cleaning batches of PCBs a lot and let me tell you, PCB cleaning solution works wonders (EMAG Platinenreiniger in my case). It is specifically made for getting rid of flux and solder balls and will clean an entire tank full of boards to almost perfection.👌 Heating it to something like 60 C will also make a huge difference.

Heated water and nearly any detergent works well. I use a product here in Australia called "simple green". But I think any basic dishwashing liquid works well. The main benefit with these is when you're cleaning "fiddly" things, with small internal ports or cavities, like a carburetor or brake parts.. The Ultrasonic/heat/cleaner will get into the smaller areas that are just too fiddly otherwise and importantly do no damage. Plus you can get on with other tasks as the cleaner works.

You might want to take a closer look at your solder paste and soldering process, so many solder balls are definitely not normal, we have like at most 1-2 per board and those usually fall off easily. It might even be bad flux.

I couldn't live without my ultrasonic cleaner, whether it's cleaning electronics, water-damaged electronics, or even for cleaning fossils - it's simply brilliant. I only have an inexpensive one from Aldi, but it does the job perfectly in my opinion, although you might need to wait a bit longer.

I've always wanted an ultrasonic cleaner as I do LOTS of microscopic hand soldering on PCBs, and cleaning flux residue is an absolute nightmare that takes up at least half the time I spend diagnosing, fault-finding, and even repairing the damaged circuits. One of the most important things I've noticed in regards to ultrasonic cleaners (and whether or not they're recommended for use on electronics) is if they feature a sweeping frequency. My understanding of this feature is it prevents the creation of standing waves within the solution. In normal operation, you will have various regions of high turbulence and cavitation, and regions with absolutely none. This is due to interference patterns emerging in the solution. Sweeping is meant to solve this problem, by causing the transducers to operate at a variable frequency. This creates a far more uniform distribution of turbulence, and therefore, the cavitation which causes microscopic water bubbles to cling to debris and gunk and pull it away. I think the reason you were having so many issues, even prior to using a specialized cleaning solution, is because this particular ultrasonic cleaner doesn't feature sweeping. It kind of makes sense that sweeping would be desired for electronic circuits, because you often have MANY small parts (the SMD components), all with various quantities of goo and debris between them. A non-sweeping cleaner would likely have lots of problems with getting cavitation bubbles to occur in all of these nooks and crannies. I also expect the full-wave/semi-wave setting on that cleaner you got is meant to create a different interference pattern in the solution. Semi-wave probably results in smaller interference patterns, which interestingly could provide better cleaning results? Maybe? The only problem with the sweeping cleaners is they are ASTRONOMICALLY more expensive. Once you get into sweeping cleaners, you're easily looking at price tags upwards of $1,000 or more! I'd be really interested in seeing a DIY attempt at creating a sweeping cleaner. I have no idea why they're so expensive, as I can't imagine it takes much more to just alter the frequency the transducers are running at. But they must be so expensive for a reason, right?

Generally, with appropriate cleaning agents in the ultrasonic, such as Branson or EMAG products, cleaning should be capped out at 1-3 minutes, to avoid unecessary damage to certain components on the PCB, of course heating should always be used, at around 60-70c

I've found I get better results with heated water, which is why the modern cleaners have a temperature controlled heater built in Also if you have those special coatings on you're glasses (like auto darkening) it might not be a good idea to put them in there

I own Two ultrasonics. One for cleaning Tarnished jewelery (I'm the maker) and one for cleaning 3d resin parts. I find them both invaluable for my proceesses. There are a great tool when you are doing low run production work because they reduce labor time.

One important thing to note: transducers should not be powered on unless mounted and the container filled to the proper volume. Testing them on the bench like that can actually damage them, with an end result that they run hotter, work less efficiently (or not at all), and also require more power from to driving circuit (which creates more heat). Even if they work perfectly fine though, i haven't seen any that didn't create enough heat to need active cooling for the circuitry. (Another note on safety: having touched an active transducer bare-handed before I can say it's definitely not recommended)

I was told by a lab technician friend that you should put the water/cleaning solution in slowly, with the cleaner turned on, and stop filling when you get the strong ripples on the surface of the water as at this point the system is at resonance and the cleaning is more effective.

Also from the safety point of view - Keep your fingers, or any other body parts, well away from the water/solution in the tank. At those frequencies, human tissue will emulsify quite readily, even though you may not feel it. It's not worth risking your fingers just save a few seconds while turning things over, or putting things into and out of the tank. My own ultrasonic cleaner recommends placing parts horizontally, and points out that the cleaning is more effective on the underside of the items being cleaned (i.e. facing the transducers).

Be sure to read through the components' datasheet before doing so. Many components cannot withstand this. Relays, crystals, buttons, pots etc etc.