Touch Based Calibration

Cartographer Calibration for Touch Mode

Initial Calibration

Touch is best calibrated for use with a clean install. We ask you remove your existing [scanner] or [cartographer] model if you have one and any other [scanner] or [cartographer] settings from the bottom of printer.cfg

Calibration can be done HOT or COLD.

Make sure calibration_method: is set to touch in your printer.cfg prior to following this page.

Home the machine in X and Y:

G28 X Y

Position the nozzle in the center of the bed. You will need to adjust the coordinates for your machine.

G0 X125 Y125

At this point, you might note that your Endstop Z is TRIGGERED, this is normal, and will be resolved once you run the next command.

Start the calibration process:

CARTOGRAPHER_TOUCH METHOD=manual

You can either use the web interface to adjust the nozzle height from the bed, or TESTZ Z=-0.01 to lower it. Use a piece of paper or a feeler gauge to measure the offset. Once finished remove the paper/gauge and accept the position.

ACCEPT

Save the results to your config file.

SAVE_CONFIG

Home your printer.

G28

You can test the accuracy of the scanner coil.

This will not TOUCH the bed. It will use the scanner to measure the accuracy of the probe coil.

PROBE_ACCURACY

You can also measure the backlash of your Z axis

CARTOGRAPHER_ESTIMATE_BACKLASH

To make use of the backlash estimation that is given. You will get results spit out starting with

Median distance moving up

In this line will be a measurement called "delta" Take note of the value. Locate the configuration section marked:

backlash_comp: 2.01

Update this section with your new estimated backlash compensation. It is a good idea to do this compensation test at all 4x corners of your build plate and then again at middle of build plate. If you are on a printer with belted Z and the values in each corner deviate heavily compared to other corners results, this would indicate a loose belt on that corner.

If you are using a printer which supports either Z_TILT or QUAD_GANTRY_LEVEL you will need to ensure that your probe is positioned above the bed when performing this, open up your printer.cfg and find the appropriate section, for example your QUAD_GANTRY_LEVEL section may look like this:

[quad_gantry_level]
gantry_corners:
   -60,-10
   410,420
#  Probe points
points:
   50,25   # Point 1
   50,275  # Point 2
   300,275 # Point 3
   300,25  # Point 4
#--------------------------------------------------------------------

speed: 100
horizontal_move_z: 10
retries: 5
retry_tolerance: 0.0075
max_adjust: 10

You should in your console navigate to each point to ensure that your probe is not hanging off the edge, you can do this using a G0 command such as G0 X50 Y25 for point 1, or G0 X50 Y275 for point 2.

If at all points, Cartographer is safely over the bed, you should be good to go for running a QUAD_GANTRY_LEVEL or Z_TILT .

You can now run a Bed Mesh Calibration (I would advise doing either a Z_TILT or QUAD_GANTRY_LEVEL before.

BED_MESH_CALIBRATE

Setting up Touch

Perform a homing.

G28

If using a printer that requires Quad Gantry Level or Z Tilt Adjust, perform that.

QUAD_GANTRY_LEVEL

or

Z_TILT_ADJUST

Once that is finished, do another home or G28 Z

G28 Z

Initiate a threshold scan. This will determine your threshold for cartographer. The threshold will determine how much force is required to touch your bed consistently.

Start by doing the generic scan

Visit here for an explanation of CARTOGRAPHER_THRESHOLD_SCAN

CARTOGRAPHER_THRESHOLD_SCAN 

This should start a touch process that will move the toolhead into a starting position and then lower until it touches the bed, repeating itself. Its okay if at first it doesnt touch the bed at all, this is completely normal. It will eventually start touching.

Prior to doing the threshold scan, please ensure that the following is true.

• Your nozzle is clean

• Your bed is clean, there are no dents or bubbles in the location you're probing.

• Your probe is between 2.6 and 3mm above the nozzle.

• Your kinematics are rigid.

CARTOGRAPHER_THRESHOLD_SCAN SPEED=2 is also available if the initial scan fails.

If however you get a final IDEAL result and it didnt touch the bed, start the process again OR adjust the parameters as follows where MIN= the found threshold value of the false positive.

CARTOGRAPHER_THRESHOLD_SCAN MIN=500 
# If 400 was a false positive

Once it finds an excellent or ideal threshold and you've seen the nozzle touching the bed. It will stop this process and move on.

Now do a touch calibration with the new threshold.

CARTOGRAPHER_TOUCH CALIBRATE=1 
# starts touch test and calibration 

If everything went correctly the touch test should pass and you can now finish by saving these variables to your config.

SAVE_CONFIG                        
# saves model and threshold