Automatic bed leveling with capacitive proximity sensor

#1

I have finally liberated my zim with the help of this group so while i now can print i still find myself spending large amounts of time on trimming the flatness of the build plate. The fact that the adjustment screws are so poorly placed doesn’t help at all.

To help with this i am thinking of getting a capacitive sensor and mount it on the side of the printer head carriage. This would still require support in the hardware so that the auto calibrate command can be run as a pre-script to all my prints.

Do anyone know if the zim hardware have any input pins for this? If so, which ones are they?
Thanks in advance, you guys are great =)

#2

you need only to connect it to Zim_MinEnd stop and modify the marlin code to have min and max endstops also add the auto bed level code and connect it to the Zim min end stop connector. Thats all that is required i have inductive endstop connected that way capacitive is the same way just is triggered by different materials, i have MK3 aluminum heatbed.

#3

Seems simple enough, does this work with the g29 command for automatically probing the bed at three points and adjusting acordingly?

#4

one thing i forgot to mention double check if your sensor is PNP or NPN i.e. if it supplies voltage or ground in the signal wire, if it supplies voltage you need to lower the voltage to 5v so that you don’t burn your board. Yes you need to Put G28 then G29 at the start code before print. You can have 3 points or 9 point (as a square grid) its all in the code and it will adjust accordingly. You will need first to install the probe at a hight which triggers the probe when the nozzle is at paper sheet hight, make a test print then check if you need to lower or increase the hight.

#5

Please elaborate on how this sensor helps you leveling with an automatic check pre-script sommand to prints.
You would still have the problems from the bed attachments and screw problems.
I improved my setup and still have to adjust before every print, I guess because of different temperatures of all parts and thus changing expansions.
I would love to get rid of leveling before every print.
But it would need to have three additional motors to automatically adjust the print bed properly.
I have seem people with a reprap printer using that solution and automatic bed leveling.

And please share some photos and or code or instrucitons if you where able to make a solution or improvement.

#6

sorry for the late reply it does measure the the Z offsets on different points on the bed and compensates while printing if the bed is not level first you need to set it properly then before every print your start code must have G28 then G29. G29 makes the printer probe the pre set points or grid and saves this reading so when printing it does the calculations. you need either and inductive probe if you have a aluminum bed or capacitive if you use glass, i use an expensive inductive probe made by keyence. i can take pictures for you but i dismantled my zim to change the controller board and put an ATX power supply inside the Zim where the lower filament stepper motors are so i am trying to figure out what each wire is since zeepro are only using red and black wires. If you need my configuration file i can post it but it would be different for you depending if you use NPN or PNP probe also the location of the probe would be different mine is next to the left extruder. Forgot you wouldn’t need to adjust the bed after doing it again because it does it for you only if you set it the first time properly.