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Changes to this Step

Edit by Jason Znack

Edit approved by Jason Znack


Step Lines

-[title] Leveling the Bed
-[* black] Every successful print starts with a good first layer. There are two factors that go into a good first layer. A clean and level print surface, and an accurate extrusion flow rate. We will address flow rate in the following tuning guide. But first we must mechanically level the bed using the 4 adjustment screws on the bed.
-[* black] This can be done with the printer turned off or on. It can be easier when powered off and you can easily move the X and Y axis by hand. Just make sure not to move them too quickly.
-[* black] Start by turning all four leveling screws so that the spring is compressed and the bed is farthest away from the nozzle.
-[* black] Now with the Z axis at the lowest point of travel move the X axis all the way to the left and the Y axis so that the bed is all the way at the front. The nozzle should be at the back-left corner.
-[* black] Turn the leveling knob at the back-left corner until the bed raises up and just touches the nozzle. You can use a piece of paper to judge this, or just your eyeball.
-[* black] Now move to all 4 corners and do the same so that the nozzle is just touching the bed at all 4 corners.
-[* black] Repeat this step a few times so that the tension on the paper under the nozzle feels about the same so it can just start to slide.
-[* black] This is just a first attempt at leveling the bed to get it close enough to successfully finish calibration.
+[title] Heater Tuning
+[* black] Heater tuning allows RepRapFirmware to find the ideal parameters for the heater model, allowing for quick heat up times, and stable temperatures, with little overshoot. For full details, see: [[Tuning the heater temperature control]]
+[* black] Ensure the test is started with the heaters at room temperature. Ideally this should be done with no filament loaded. For most accurate results, set the part cooling fan speed to match normal print fan speeds. For the Ender 3 and PLA that would be 75-100%
+[* black] Next send M303 H1 S210 to start the heater tuning process for the hot end. Wait for the process to complete. It should only take a few minutes. Save the results by sending M500 so that they are loaded automatically at startup.
+[* black] If you followed the configuration guide, automatic loading of the config-override file should be enabled. If you get an error message saying otherwise, add M501 to the end of config.g
+[* black] Next tune the bed heater by sending M303 H0 S60. Wait for the process to complete, and once again, save the results by sending M500. Note that bed heater may take considerably longer due to increased heat up and cool down time.
+[* black] The temperatures chosen reflect the most common temperatures used for printing PLA on the Ender 3. If you plan to print with other filaments that require hotter temperatures, you can re-tune with those. However, the results of the tuning at these lower temperatures will still be valid over a fairly wide range of temperatures.
+[* black] Also keep in mind that the stock Ender 3 Pro has a PTFE tube in the hot end which should not be exposed to temperatures above 240c due to the foul smell released. And the heated bed uses a magnetic surface which should not be exposed to temperatures above 80c due to the damage it can cause the magnets.
+[* black] PID tuning should be redone whenever a major modification is done to the hot end or bed heater, such as installing or removing a silicone heater block sock, or changing the part cooling fan, or even if the ambient temperature of the room the printer is in changes from season to season.

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