Print on existing object

[yaire 0]

Hi,

 

 

I need to print on a polycarbonate panel of thickness 10 mm, that I stick to the glass build plate.

I found out a way to overcome the problem, but I am searching for a way to "tell" the printer to practice active levelling on the panel (  and not on the build plate ).

 

What I am doing for now is:

 

- Z offset at 10mm in Cura

- Launch the print WITHOUT the 10 mm panel

- Wait until active levelling is finished

- Put the panel on the build plate, and the print starts

 

I wish I could tell the printer to practice active levelling on the 10mm panel, because for now, the printer collides with the panel when practicing active levelling with the panel on the build plate.

 

Is there a way to do that ?

 

Thanks,

[Labern 775]

When the printer is active levelling it has a sensor that is reading the aluminium plate under the glass. Putting an additional 10mm of plastic on top of the glass would probably put it out of the sensors range so it won't work. 

The only thing I can think of is to put tin foil on top of your 10mm panel. It would have to be without wrinkles and then quickly remove it after levelling (if it works) when the cores are heating to print. 

The tin foil should be thin enough to not offset your bottom layer any more but may get damaged during levelling.

[UlrichC-DE 114]

I can only speak for the S5.

The proximity sensor for the level is built into the print head. Pressing the print heads causes the sensors to be triggered. (Not the aluminium plate under the glass)

The leveling cannot be switched off at S5. Ultimaker does not want that. The reasons for this strange.

If you are interested ... at the bottom of the thread is the explanation:

 

You can try hacking it.

- Put 10mm plate on Glas

- "first" perform a manual calibration!

- then to the automatic calibration (can unfortunately not be switched off)

Important (and self-explanatory) is that all calibration points are 10mm.

Theoretically it should work like this (no guarantee)

 

I would do the testing and then mill or print a fixture that emulates all calibration points.

 

Just an (bad) idea

 

Edited August 13, 2020 by UlrichC-DE
Something wrong

[Labern 775]

On the S5 The sensor in the print head is measuring the alloy plate. As the print head gets closer the sensor reading is increasing. When the print head touches the glass the sensor reading stops increasing and stays constant. At this point the printer knows that it is touching the glass and stops. 

[UlrichC-DE 114]

Thanks, I didn't know that. But it sounds logical.

 

So maybe you could try to put a thin steel plate through the glass to trigger the sensor through 10mm?

[UlrichC-DE 114]

 

1 hour ago, Labern said:

On the S5 The sensor in the print head is measuring the alloy plate. As the print head gets closer the sensor reading is increasing. When the print head touches the glass the sensor reading stops increasing and stays constant. At this point the printer knows that it is touching the glass and stops. 

 

Now I have another problem.

Which sensor senses that the print core is being pressed?

The sensor is not fixed to the print core. The sensor approaches the plate the measured value increases further .

Only the print core moves away from the sensor.

Edited August 13, 2020 by UlrichC-DE
Maybe you're wondering what I'm asking. I don't want to seem smart. I just want to understand.

[Labern 775]

It's ok, I don't think your trying to be smart. A lot of people have a misunderstanding of how it works and it's good to know as it can help problem-solve if you do. 

The sensor is on the bottom of the print head. It's on the bottom of the front fan door. If you open the fan door and look inside you can see 2 wires connecting to the base. That's the sensor. 

 

You can read about how it works HERE as it is the same one as in the UM3 and this link has a full better description of the whole background of how's it works and why. The only difference is on the S5 it has more measuring points not just 3 which helps it compensate for imperfections in the glass and also you can't turn off the feature.