Using Ultrasonic Printing to Unclog Printheads: Can it Work?

The ultrasonic cleaner works wonders in unclogging printheads, especially the printheads clogged by pigment ink. The cleaner is highly effective and very affordable. They can be found on eBay for about $30 to $100. However, many people are saying that ultrasonic cleaner will destroy the printhead. So let's take a look at the ultrasonic cleaning process more carefully. Ultrasonic cleans a surface by cavitation, which the ultrasound creates microscopic bubbles. When the bubbles burst like that they will make a tiny vacuum.

Millions of these bubbles will create a cleaning force and dislodge dirt and debris from the surface of whatever we are trying to clean. This process sounds very harmless, so how could it destroy the printhead? It turns out the vibration of the process is detrimental to the thin surface- thin membranes. If you have a thin membrane, they are probably going to get destroyed. Therefore, although ultrasonic cleaning is widely used in automotive, sporting, printing, marine, medical, pharmaceutical, electroplating, disk drive engineering, and weapons, we shouldn't clean things like microphones, speakers, buzzers, accelerometers, and gyroscopes, and some of the printheads.

One way to test the power of cleaning is called a foil test, in which an ultrasonic cleaner will destroy a piece of aluminum foil in seconds. Many people are scared of destroying aluminum foil and conclude the process is very harmful to the printhead. However, the aluminum foil test is unique. In addition to the physical forces of high-frequency vibration and caustic cavitation, a sonochemical effect occurs that causes the molecular bond cleavage of the water molecule to release powerful oxidizing hydroxyl radicals. Because of the nature of aluminum, the result is dramatic.

The ultrasonic is very safe for electronic parts, as long as we know which one can't be used and which one can. For print industries, ultrasonic cleaning is widely used on printheads such as HP, Canon, Epson, Mimaki, Konica, Seiko, Nova. However, some of the printheads have thin membranes to divide ink colors. Therefore, there are individual printheads that we shouldn't use the ultrasonic cleaner. So how do we decide if we want to try ultrasonic cleaning? We need to do plenty of research and only try on the kind of printhead that we can afford to lose.

Here's an example of an ultrasonic cleaner destroy a DX7. If you don't know, DX7 is about $1,500 and $500 used. It is clear that the vibration destroyed the sealing membrane, and we thank the author very much for trying that and then share the result with us. However, don't believe everything you see on the Internet. For example, we'll give less width to this information because the author didn't try it and only provided some speculations. Finally, we need to decide what kind of ultrasound machine to use. Let's take a look at our plan here. If we use the following configuration, the ultrasonic force will clean the surface of the printhead.

Also, if we fill up the printhead with a liquid such as ink or otherwise, the vibration will knock off some debris inside the nozzle. Therefore, the outside cleaning is done by evaporation and cavitation- cavitation, I mean bubbles- but the inside cleaning is only done by evaporation. To make the bubbles inside, we want to have a smaller bubble-like in picture B. If a pigment is thick inside the nozzle, we can have both sonic waves and cavitation bubbles to dislodge it. The ultrasonic frequency determines bubble size. The higher the frequency, the smaller the bubble.

We will see in this figure. Most printhead sizes fit in the red band. Therefore, if we use our 48 kHz frequency, we can have the bubble small enough to fit in the largest nozzle. To make the cavitation bubbles work for all nozzles, we'll need about the same 75 kHz and above—however, most ultrasonic cleaners, 40 kHz and below. To get 75 kHz and up, you'll be expected to pay at least $1,000. Don't be discouraged by this information. We're talking about cleaning the nozzle hole. Although the nozzle opening is tiny, it immediately connects to a large funnel. The less expensive cleaners can still do an excellent job on the printhead.

BCH carries some high-frequency cleaners. If I have money to burn and here's a good source, go to the BCH website, go-to accessories, and check the ultrasonic cleaner. The cheapest one is under $1,000. We're going to use a regular 40 kHz cleaner. Then we need to decide how powerful we want to be. Do we want our 35 Watts cleaner for $30 or 350 watts for $300? Fortunately, neither the bubble size nor the cavitation power is determined by the power of the cleaner. More powerful cleaners will have more bubbles and thus clean the surface quicker.

However, we can get a regular small-size cleaner and do just fine. Therefore, we can choose a small cleaner. If you are choosing a larger one, then you may be overcompensating something. We're going to use a Canon Cartridge PG-245. This cartridge is an integrated cartridge, which means it doesn't have a membrane or foils. We modified the original cartridge and made it a spongeless refillable cartridge. If you want to know how to do that, check out the link below in the comment section. I'll mark it as a first printout, no cleaning. We use a little cleaner, a cheap cleaner we bought from eBay. You always want to use a basket to suspend your printhead right on top of the bubbles.

We cleaned the first day, then we left it overnight, which is the second day. We did 20 cleanings total and 90 seconds each cleaning. Let's check the result.

Here's the result of five cleaning and the 20 cleanings—the last to mean, the check out little details. Typically a Font Size of two is the limit the Inkjet can do. If you see the letters on the Font Size two, after 20 cleanings, they look much better.

Okay, I know what you guys are going to say. You guys will say the little machine we use here is too small, and you want to see the high-frequency device. Okay, you got what you wished for. I'm not too fond of the stainless steel basket, so I bought this cookie sheet or some silicone pad from Joann Fabric. I plan to cut a hole and use it as a floating platform.

Those cartridges have a nice angle. So I'll sit like this so that it won't rub the printhead on the stainless steel.

We did 20 more cleanings, three minutes each. So the total clean time with this is an hour.

We've cleaned this printhead 40 times. Used high-power, low-power, high-frequency, low-frequency. We conclude, there's no way you can destroy the integrated cartridge with ultrasonic cleaning. We're looking at things on a tiny scale. Let me compare it to a commercial printout on the product page.

After 40 cleanings, the letter's still very sharp. So we think ultrasonic cleaning is safe for integrated cartridges. The integrated cartridge is like HP and Canon, and they look like this. A little black square and a header printed on them.