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Jyers / Marlin

Marlin is an optimized firmware for RepRap 3D printers based on the Arduino platform. | Many commercial 3D printers come with Marlin installed. Check with your vendor if you need source code for your specific machine.
http://marlinfw.org
GNU General Public License v3.0
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Homing with Bltouch and Z end switch as a backup #1967

Open zaggash opened 2 years ago

zaggash commented 2 years ago

Description

I'm using the latest E3V2-UBL-BLTouch-10x10-v4.2.2-v2.0.1.bin

During the Homing, the Z-axis is stopped with the help of the BLTouch which is good and expected. However, I tried to manually press the Z End Switch manually during Homing but it is ignored.

What if the BLTouch fails ? or doesn't work correctly? The Nozzle would hit the bed.

Is there a way to prevent that and make Bltouch and Z end switch as a backup?

Feels like a bug to me since we have a dedicated port on the motherboard for the BLTouch

Steps to Reproduce

  1. Flash with E3V2-UBL-BLTouch-10x10-v4.2.2-v2.0.1.bin
  2. Home the Printer
  3. Wait for the Z Homing.
  4. Force the Z stop with the Z End Switch

Expected behavior:

The Printer should stop the Homing session and raise the Z

Actual behavior:

It does nothing.

zaggash commented 2 years ago

The BLTouch replaces the Z-Endstop if you wire it into the Z endswitch on the motherboard. Why is there a way to wire both BLTouch and Z endswitch on the motherboard separatly then?

I stumbled upon this convo and it gets closed because of inactivity. https://github.com/MarlinFirmware/Marlin/issues/15731 I wonder if it would be a nice addition to the community firmware.

I know it is on the configuration.h but it doesn't mean it is not possible to make it work with a bit of configuration knowledge on Marlin.

amandamana commented 2 years ago

There are some good arguments in that linked convo, and another convo linked within it. I'd love to set my Z-Endstop 1.5 mm too low and use it to protect my bed in case of a probe failure.