Set Z offset in Cura

[clems 1]

Hi ultimakers,

i want to print directly onto different objects which have a height of 1, 3 and 4 mm. Is there a way in cura to set the z value, so that the starting z-value is 1,3 and 4 mm above the printbed. I do not want to change the z-stop manually as I need to change the value of the z a lot.

Hopefully someone can help me!

Regards

Clemens

[nallath 1,117]

Cura has no such feature. It only has very limited uses cases and makes the workflow much more complicated / confusing. With a little bit of g-code tweaking you could implement this yourself (Do a certain move before you start and reset the zero position).

If you want to make that automatic and know a bit of code, you could use https://github.com/nallath/PostProcessingPlugin

[neotko 1,417]

I think you have 2 options, ofc making a plugging would rock.

- Simplify3D has Z offset (150€ slicer no demo to test)

- Attach something of 1.3mm to the piece that hits the Z sensor (design + print). On umo the wood would let you screw something to it probably, on um2 I think it's a screw that hits the sensor on the lower part, so that could be trickier since you need to remove distance. Maybe unscrew it 1.3mm?

Droping ideas

[clems 1]

Cura has no such feature. It only has very limited uses cases and makes the workflow much more complicated / confusing. With a little bit of g-code tweaking you could implement this yourself (Do a certain move before you start and reset the zero position).

 

Thank you for the hint. I changed my starting gcode:

G21        ;metric values

G90        ;absolute positioning

M82        ;set extruder to absolute mode

M107       ;start with the fan off

G28 X0 Y0  ;move X/Y to min endstops

G28 Z0     ;move Z to min endstops

G92 Z-3  ; reset the position

....

After moving Z to min endstops. I reset this postion to the negativ height of my objects.

That is now easy for me.

Edited August 19, 2015 by Guest

[AnthonyRich 0]

This still seems to be a still problem in Cura 3.6. I'm one of the poor people that can't afford a multi-color extruder nor a Mosaic Palette. My use case was:

• I wanted to print a 3.2mm thick base plate in one color.
• I wanted to change the filament to a different color.
• I wanted to continue printing letters on top of the base plate (i.e.: starting at Z=3.2) using the second color.

I didn't want to mess around with the G code files after Cura generated them, but I did have control of the source STL files. So my work around was to generate the STL file with the letters at the correct height and include a 3.2 x 0.5mm (h x d) post outside the build area of the base plate.

 

If I tried to make the post 0.4mm or less (the diameter of my nozzle) Cura would exclude it from the G code and start the G code of the letters at Z=0 instead of Z=3.2.

[geert_2 556]

If you wouldn't mind babysitting the printer, you could make it all in one design (=one part in one STL-file). And then manually pause the printer at the appropriate height, change filament, and continue?

 

If you would print a dummy block next to the real print, you can hit the pause button while it is on the dummy block at the right height, so it doesn't stop halfway a layer in your real model.

 

Not practical, but it might work. There are people who do similar things to insert metal (or other) inlays halfway a print.

 

[ahoeben 1,845]

Have you tried the Z Offset plugin from the Marketplace?

[AnthonyRich 0]

4 hours ago, ahoeben said:

Have you tried the Z Offset plugin from the Marketplace?

 

I did have a look at fieldOfView's "Z Offset Setting" plugin in the Marketplace but I didn't think the "Build Plate Adhesion > Z Offset" setting was having any effect because Cura's GCode preview was still showing the GCode sitting on the build plate.

 

After your comment I broke out KDiff3 to have a look at the resulting GCode (I know GCode, I just don't want to hand edit it) and confirmed that it is actually modifying the GCode Z offsets. Before:

;MESH:lorem-ipsum.stl
G0 F7070 X-2.177 Y0.813 Z0.3

 

After:

;MESH:lorem-ipsum.stl
G0 F7070 X-2.177 Y0.813 Z3.5 ;adjusted by z offset
G92 Z0.3 ;consider this the original z before offset

I haven't tried printing with that yet, but it should work ok.

[ahoeben 1,845]

I’m fieldOfView on github.

[tommyph1208 55]

I'm pretty sure I did something like that using a negative "cut off object bottom" value... (old version of Cura though)

 

[hgutierrez 0]

To print different colors on top of something already printed I generate anther G-code where I used support blockers with the height that is already printed and change the per model settings to Zero for: Wall Line Count, Top Layers, Bottom Layers and Infill. 

That ensures the bottom section will not be printed and the new color will be printed on top of the previously printed part.

To prevent the extruder to crash with the already printed part, instead of building a waste tower I add a line of code to raise the extruder to a height that will clear the previously printed object.

 

Example: The first print is on layer 147  height 29.6mm

 

G0 F6000 Z31  (add this line to raise the extruder to 31mm before start of the print)
;LAYER_COUNT:370

;LAYER:147

G0 F6000 X153.1 Y138.3 Z29.6

 

For more complex prints I also add a line to move the extruder to the exact X, Y position