I have the following setup:
Ender-3
4.2.7 Silent Board
Creality CR Touch and Creality Silicone leveling cylinders
Creality Tempered Glass Build Plate
Firmware: Ender3Marlin2.0.6HW4.2.7BLTouch.bin Firmware from “Ender-3 Marlin2.0.6 CR-touch or BLtouch firmware”
I have two problems
1- When I tell the Ender-3 to level the bed it probes 9 points but they are off. The three probe points in the front of the bed are on the very edge of the bed (front edge of the probe is about 2mm from front edge of the bed (the probe does touch on the bed though). All probe points are about 1.5cm to the right of where they should be. It’s almost as if it’s probing with a different sized bed in mind.
2- The print head corrections that the probing stores seem to be lifting the extruder near the middle of the print causing the outer portion of the first layer to have reasonable bed adhesion, but the center first layer gets messed up every time.
My procedure:
1- Clean the bed with 70% alcohol.
2- Heat the bed to 65C.
3- paper level the four corners.
4- get z-offset value by auto home then lower z-axis until I encounter resistance with paper.
5- Enter the z-axis offset value (-000.50) and store settings.
6- Auto Home
7- Level Bed
8- Print
My expectation is that the CR Touch would compensate properly for bed inconsistencies and probe in the correct places (above each leveling screw, in the center and north, south, east and west). I suspect my problem #1 is contributing to problem #2.
It sounds like your probe offsets are not set correctly causing the printer to probe a particular area that is not in relation to where the nozzle will be printing.
I would recommend going into your printer settings and ensuring that you have the offset of the probe X and Y values correctly set. As far as I am aware the settings for the Ender 3 should be X: -45, Y: -5.
Once those values are correctly set you should find the probing will be in the correct places.
I am slightly confused by your step 4 in your procedure… once you have all 4 corners leveled the z offset should usually be calibrated during the first layer of the next print you make. If you alter the z offset in the center of the bed then you are effectively voiding your values that you got from the corners of the bed as the center is always generally lower than the sides. I would recommend checking your probe values and ensuring that the leveling of the bed is redone.
My step 3 is the old method without using z-offset. At step 3 z-offset is 0.000. I go into move axis > z > then drop it down to zero after an auto home. I disable the stepper motors them manually move the x/y of the extruder to the four points and turn the bed level screws until the paper encounters some resistance.
In step 4 I’m following the Creality CR Touch Z-offset instructions which tell you to auto-home then use move axis > z > and record the value once it’s low enough to cause resistance on the paper, then go into bed leveling > z-offset and set that value. Then store settings. Are the creality instructions wrong?
I looked in the creality firmware menus and I can’t seem to find where I can set the probe offsets. I’ve seen youtube videos of the Ender 3 and CR Touch probing in correct places, so I know mine is off, I just don’t know where to change them.
Ahhh ok that makes more sense, thank you for the clarification. At first I thought you were leveling the bed in step 3 and then adjusting the bed again in step 4, now that you have explained the process of step 4 I completely understand your procedure and can confirm you are doing it correctly
As far as I am aware there should be a setting in the Probe or Advanced menu for the X and Y offsets. If you do not see them listed then it could be that the adjustments need to be made using a different method.
Thanks for the help. I found the probe offsets in Configuration > Advanced Settings > Probe Offsets. I ended up with X: -73.0, Y: -8.5 to get the probe points to be centered on the build plate. I ended up needing to redo the z-offset at this point because it changed slightly. A couple things I noticed:
1- With the new probe offsets, this also changes the Auto Home Z probe point which is to the right of center by about 3cm. I feel like this is a recipe for incorrect z-offset points if I follow creality instructions to Auto Home then move z-axis to get the z-offset value, because it’s not getting that from the middle of the board.
2- The board leveling is now much better, but I still find that I needed to make minor tweaks to the board leveling knobs because in some places I was getting extruder gear slipping because the extruder nozzle was too close to the bed during the test print and the extruder was not able to extrude filament, which increased pressure and caused the extruder gear to slip.
Is it normal to level the bed with a CR touch but still have to make fine-tuning tweaks to the bed leveling knobs?
You might find that the 3cm that you are off by is due to the difference in your X offset, the values used and tested with most users of that printer and probe are an X value of -45. With yours being set at -73 that could explain the 30mm difference that you are seeing. I would recommend using the -45 value.
I am glad to hear that the bed leveling has improved since being able to correctly configure the offset of the probe to the nozzle in the X and Y. When it comes to the nozzle being too close to the bed during the print dont touch the bed leveling knobs at all as you will effectively completely void the mesh that the printer created when probing the bed. What you should instead be doing is using the control panel on the printer to access the Z offset menu and adjust the offset whilst printing rather than touching the bed knobs. This will ensure that you dont unlevel your bed by touching the bed screws and will also mean that the Z offset you apply on the printer once saved will apply to all future prints.
When it has a negative value on the z-axis compensation what does that value represent as far as set up goes. After auto levelling on the 3040 Pro during print it shows -1.81, is that the height of the nozzle above the bed?
