Hi, my name is Josef Prusa, I’m the creator of Prusa i3. In this first video in series of three I will showcase the new MK3. In this video I will help you with the first print of a freshly assembled printer. I hope you followed the manual, especially the chapter 9 “Preflight check”. First is the power up. You can use the toggle switch on the power supply. Then the printer greets you with the language selection So I’ll select English. This is the control knob. When you want to confirm something, you just press it. Down below is the reset button. If the printer is doing something weird or you are not sure that everything is going… …going right, you can just press it and the printer will immediately stop. I select English, but if you accidently select different language you don’t understand, you can just do the factory reset, which is mentioned in the handbook. Printer greets you with the Wizard which guides you through the setup process. If you accidentally hit No. You can always go to the Calibration menu… …and run it from there. The first part of the Wizard is the selftest which checks all the hardware parts of the printer. So we just run it from here. First thing the seftest checks are the print fan and nozzle cooling fan. Both are okay. Then it tries to heat up the hotend and monitors the temperature change if it heats up fast enough. The hotend is okay. And then the printer continues with checking the x-axis It goes back and forth and measures the length of the axis Now the same for the y-axis And now for the z-axis. This also checks the P.I.N.D.A probe. Everything is okay, and the printer continues with the bed heating. Again in heats up the bed and waits for the temperature to raise. This printer was perfect, but you may encounter some errors during the selftest. But you can find the resolutions for all of them in the handbook and also in the upcoming video… …about the errors. Next step is XYZ calibration, which measures the geometry of the printer. It will take roughly 12 minutes, so just confirm. First thing the printer will align the z-axis because if it’s at an angle we will just go all the way up. Until both sides hit the top, which will make it level. Be careful if you put these lead screw nuts the other way around, the z-axis may not reach all the way to the top. Then the printer asks you if you have the sheet on. I select yes and it asked me to remove it. It needs to be removed for the first part of the calibration. Next step is to check if the nozzle is clean. In my case it is clean, so I confirm. Get a piece of paper ready… …and during the calibration we will place the paper… between the nozzle and the heated bed… …and we will hold it all the time. If the printer or if the nozzle catches on the paper it is a sign that something is wrong and you should try readjusting the P.I.N.D.A probe and you can quickly abort the… …the calibration with the reset button. It’s still important to hold the piece of paper between the nozzle and the bed. Because if you… …if you remove it and walk away, that’s exactly the time when the nozzle will dig into the bed. Ok the second round of the… …skew calibration is done. And then printer asks you to place the steel sheet back. The sheet has two notches on the back and there are two pins on the back of the bed. So you can use this to align the bed (sheet) exactly on the on the bed. Perfect. Okay, we confirm. Now it does the full nine point Mesh bed leveling. The printer now stores the height of all the nine points on the bed and stores them in the memory. It does this before ever print, and if the values are different by large margin the printer knows something is wrong and ask you to check. For example if something was under the sheet. Okay, so the XYZ calibration is done, and we got perpendicular the best result. Let’s continue. Printer asks me if the filament is loaded and we select no and prepare the the filament. It is important to have a nice sharp tip and you can use pliers or side cutters to make it so. So the filament is not loaded. Now the nozzle will preheat, and then we will place the filament in the top of the extruder. In the meantime it is very important to place the spool on the printer this way so the filament goes from the top to the front. If you do it other way the filament might require too much force to… …unspool from the spool. Okay. Printer asked me to insert the PLA into the top of the extruder and confirm. Now it’s loading the filament. You can watch until the filament will start to go from the nozzle. Okay the filament is loaded and you can remove it. Be careful not to touch the nozzle, it has 200 degrees Celsius which will burn you. Next step is the first layer calibration, where we will set the distance between the nozzle and the steel sheet. Before we do so we need to clean the bed. We ship the printer with alcohol prep pads, which is isopropyl alcohol, so you just open one and… … wipe the bed with it. Be careful not to touch the nozzle. Good. Now back to the printer. We will start the first layer calibration. It is really important that the steel sheet is on the bed. You cannot print without it. The printer jumps into the main menu and starts preheating everything. It does the Mesh bed leveling, all the nine points. Then it prints the intro line to stabilize the pressure in the nozzle. And you can see the new menu on the LCD. Adjusting Z. So you will scroll down… …until you see that the line is nice and stuck to the bed. The value will be somewhere around minus one millimeter. We just watch the the line and adjust it until it’s nice and squished. You can see the picture how it should look in the handbook. I’m pretty well set up, my value is minus 1.15, but it will differ for every printer. When the meander finished, you can see that it will start to print a small square piece where you can check the distance is properly set. You need to let the printer finish this file completely. Because otherwise the value will not be stored in the memory. Before you run it again, you need to remove all the stuff from the bed which should be very easy to do with just your bare hands. And now we need to clean the bed again. To clean the bed best is to get the isopropyl alcohol. That is for everyday cleaning before ever print at least 90 percent or more. In case you cannot get isopropyl alcohol. You can use Windex, which isn’t as good, but will also work. And you should also get some acetone, which you should use at least once a week or when the prints stop sticking. It rejuvenates the surface of the bed. We don’t want to run the first layer calibration again, so we just click no. Okay, so the wizard is done and printer wishes you happy printing. Now we are ready for the first print. First we will need to clean the bed again, so I’ll just get tissue and some isopropyl alcohol. And gently wipe the bed. Good. First we will preheat the printer. So just go to the menu, select preheat and select PLA. When you are testing your first print it’s very important to run the g-codes from the SD card because they are tested. So now we will start the print from SD card which is placed here. So just go to the menu and select print from SD. And the first print we will do is… MK3_PLA_Prusa, which prints a small badge with the Prusa. As the printer was preheated it should start printing immediately. Again the printer does the mesh bed leveling first. Then it starts with the intro line and moves to the print. If you feel that the first layer is not stuck enough or if it’s too low you can go to the menu and… …call Live adjust Z where you can set or readjust the distance between the nozzle and the sheet. Now I will tell you something about slicing. If this is your first printer. I strongly suggest to use the Prusa Control. It is part of our drivers package, which also includes the sample objects. It is pretty simple you just drag and drop one of the objects into the main window of the Prusa Control. You select the material print quality and infill. Then you just hit generate and wait. When the generation is complete you just save the gcode on to SD card and put the SD card into the printer Now the print just finished, and I’ll show you how to take it off. Now you just clean the bed, and you are ready for another print. Congratulations to your first printed part. In the next video I’ll show you how to resolve the errors you might encounter during the setup process. Thank you and happy printing.