 Hey guys, it's Kevin. I'm going to share some experience coloring this HP printhead. I'm using the printhead 910. I hope you can shine some light to when you clean the other models, like 936, 902, 564 printheads. I have hundreds of those printheads to refurbish. And what I do is I use this cleaning kit. I'll put the link to the kit above. And on here, you can see there's a video here. You can see how I do it. Let me define when I use the printer's building function. I call it cleaning. So here I do three cleanings. Then I will inject this cleaning solution in the printer. Leave it for 12 hours. I call it flush. And then I will clean it three more times. So this is full circle. The detail is on that video on the page. And you can look it up. Oh, actually, let me double check with somebody doing it hundreds of times. How many cleanings do we do before we flush it? I mean, the first time we put the printhead in, you mean like how many times it runs? It runs three times? Three times. And then we flush it. And then we do three times. Yeah, three times. So what's the percentage of the printhead that is good after that? Most of them not really are good after that. Your dip sometimes takes like two flushes maybe. Two flushes, normally. So the one we had problem is like after two flushes. Yeah. OK. This one, that one might have been two or three flushes maybe. OK. But I'm going to... OK, so normally it runs pretty smooth. We do two or three cycles. And we can pick it up and sell it. But recently she brought me those that after two or three cycles, you're going to see same color all the way across. Then you'll do one more cleaning. One color will be really bad. So you can see the magenta and yellow that they're good. But blue or cyan is really bad. However, just one cleaning before, the cyan is perfect. And however, the every color is cyan. It's weird. Because it's after two or three flushes or cycles, she brought those to me. And usually we just consider them bad and threw them out. And before throwing them out, I'm going to do some experiment. So this video is about that. I took this video before the experiment. And pay attention to the ink channel. You can see the ink moving in there. It's going to be important afterwards. And take a look again. Can you see it? First thing come to my mind, of course, is ultrasonic. I usually do not do ultrasonic for Epson. Because Epson's print that is based on Pizzle Jet, which is a membrane technology. If you don't know Epson, you might damage it. Pretty much if you don't have experience with Epson, don't do it. However, for those HP or Canon print that, I usually do it all the time. And you can see my other videos that I just nuked. I nuked like 20 minutes. You just put the print out on a plastic basket. And fill the fluid level. You can use just water. Or you can, like me, if you have a lot of cleaning solution, you can fill the cleaning solution. Fill it just a little bit above the bottom of the print. So you don't make it the electronic parts wet. Ultrasonic is going to create millions, millions of tiny bubbles inside the print head. The bubble is going to push the ink up. However, you can see the blue or cyan doesn't have enough fluid going up. That's interesting. I run it for three minutes. So the end result is actually I killed it. And there's just a blank page after I cleaned it. And then the second cleaning, just a really tiny color comes out. So in my conclusion is, don't do the ultrasonic more than, either do not do it at all. Or if you do it, don't let me put it in three minutes. Maybe try it for a couple of seconds and just gradually increase. Safe works. Once I get more of those bad print heads, I'm going to try the ultrasonic again. This morning, finally, we got a print head that cannot be cleaned after two cycles. You can see it has the same problem. I print almost perfectly. However, they all in the same color. I'm cleaning again. One color is gone. The other color remains perfect, almost perfect. So thinking, it can print nicely in one color. So it's not clogged on the nozzles. So maybe there is something wrong on the ink supply. Either the cartridge is not sealed properly. Oh, there's a ink clog in those chambers. And there is definitely not a problem on the nozzles. That's working on this part. So instead of inject the cleaning solution directly, I first draw the ink backwards. So if anything in the tube, so if there is something blocking the ink channel, it will be sucked back to the syringe rather than be pushing forward to the nozzle. And then I inject the fluid and wait 12 hours and clean it. Secondly, the HP's seal is terrible, the black seal. So I put one extra layer of washer. I'm going to put the link to the washer above. So I double it. And those washers are very easy to install. Just a larger portion towards back, a smaller portion to the front, and you lay on top of the black seal. So this one, I double it up. I use two washers. Just to make sure. If you have a neck gap, the printer is going to suck air into the printhead rather than ink. Flush, 12 hours later, the first cleaning doesn't look bad at all. And second cleaning and third cleaning. If in the future I have other printhead cannot be cleaned and we're going to throw away, I'm going to try the ultrasonic cleaner and I'm going to share it with you. Just in case you want to see what America looked like at the peak of Omicron, I got upgraded to the first class because there are only three passengers. On the way back, the flight attendant asked me if I want to take half of the plane or I want to sit with other first class passengers. I feel like I have my private plan and my private airport, just me and my pilot. 2 o'clock in the afternoon, Washington International Airport. When I got into the airport, there were just me and 30 lanes of TS agents. Each lane has like four or five people. So it's just me and 150 TS agents. They all look at me. And there's somebody said, lane 21. And I said, can I do 30 because it's closer to me? And the lane 21 said, no, we'll take turns. Do you think it's easy to get to 21? OK, I hope you enjoyed this video. Visit us at www.bchtechnologies.com or locally. Greensboro, North Carolina. Cheers.