My 3d touch risks leg breakage🧐!

dieterdd

Hallo!
Is there any way to turn off the BL-touch after work is done while printing? (He also means to want to stretch out his little foot again and again during printing, and that could well cause a "leg fracture".)

Good greetings
Dieter

fcwilt

@dieterdd

Hi,

It should stay retracted during printing.

Is it not doing that? Is it extending randomly or in some kind of repeating pattern.

Frederick

Hernicz

@dieterdd The wires of your BLTouch are too close to the wires of your stepper motor. The inductance (magnetic field generated by electricity around the stepper wires) make your BLTouch deploy randomly.

If you put all the other wires (fans, heater, thermistor, etc) between the two (like a sandwich) and keep them 2-3 mm away it will not deploy on it's own.

oliof

Or twist/braid the servo/ground wires to protect against induction.

dieterdd

Thanks for the quick replies!
@fcwilt: randomly.
@all: yes I know that it comes from the interference of the stepper motor for example. Maybe I can find a shielded network cable ...

Since I build a large printer (100x50x50 ) I have very long cable runs (from the duet3hc6 to the print head ca.3.5 meters) there is a "cable sandwich" difficult to realize.
And every cable exchange is a small challenge.

So it would be much easier to simply switch off the BL-touch after measuring the bed. Because then he must deliver nothing more.

Is there no command for this?

dieter

(Hey Frederick, I also have a Hobie Tandem Island )

Hernicz

@dieterdd You would need to define a 5V fan output to switch power to the BLTouch by GCode (or make the IO switchable, I don't know, not around printer), but I don't suggest doing this.

You have a hardware issue, which needs fix. I wouldn't try to fix it from software side. It can still have issues if you do Mesh probing while the Extruder motor is powered (it doesn't have to move, just being powered is enough).

If you take off the plastic from the Duet side connector you can probably pull out the BLTouch wire.

fcwilt

@dieterdd said in My 3d touch risks leg breakage🧐!:

Since I build a large printer (100x50x50 ) I have very long cable runs (from the duet3hc6 to the print head ca.3.5 meters) there is a "cable sandwich" difficult to realize.

One of my first printers had long wires to the extruder since I used cable chain on both the X and Y axis.

I don't do that anymore. I now use Zesty Nimble remote drive extruders which have the flexible "drive shaft" running from the frame to the extruder (under a meter). I use that to carry the wiring.

You can do something similar using spring steel strips or rods from the frame to the extruder and use that to carry the wiring. The E3D motion system uses this approach.

(Hey Frederick, I also have a Hobie Tandem Island )

The two person version?