Slice Hollow part with open end

[pander1405 0]

Long time reader of these forums here. I finally am stumped and need help.

 

I have a Christmas tree STL, I am wanting to print with 0% infill and leave a hole in the bottom for a tea light to fit. I want to hole in the bottom to be open in to inside of the tree.

 

I add the tree to Cura and add a cylinder the size of the tea light. Align the 2 parts at the center of the plate.

 

Set infill to 0%.

 

Select the tea light cylinder, go to Per Model Settings then Modify settings for overlap. Uncheck Infill only and change Top Layers and Bottom Layers to 0.

 

Cura leaves a cap where I want the tea light open to the inside. How can I correct this?

 

See picture.

[Torgeir 264]

Hi pander1405.

 

Welcome in here.

 

Here was little information for sure, -however, you tree seems to be "all solid" so you'll need to define the wall thickness.

Maybe better to set number of wall layers single wall one, two, or what you want.

You might need support, -or maybe this can be printed without using support.

 

Good luck

 

Thanks

 

Torgeir. 

[pander1405 0]

Hello Torgeir - thank you for taking the time to help.

 

I have also tried another method. This is explained below.

 

First, I model exactly as I would like to print. A hollow tree with 1.2mm wall thickness and cylinder cut from the bottom. See first picture below.

 

Add the STL to Cura, set infill to 0% and slice.

 

A very similar result is produced. Any ideas here? Maybe there is a settings I need to turn off in Cura?

[Torgeir 264]

 

Just select; "Color scheme", then select; "Line Color".

Then we'll see what is making the bottom "light yellow circle part" of filaments.

Then this might be possible to deselect in Cura.

 

If you're using say "0.4 mm" nozzle, you may then set line width to 0.4, -then three layer make wall thickness of ~1.2 mm.

 

Thanks

Torgeir

 

 

[pander1405 0]

Torgeri - I've attached both Cura files for your review. Maybe you can achieve the desired results more efficiently.

 

I've also attached desired STL.

Tree_hole_export.3mf Tree_per_model.3mf Tree_w_hole.stl

[Torgeir 264]

Hi @pander1405,

 

Took a while this, Cura did not cope with this issue. So there where two options, Meshmixer (or alike), or just remove that gcode parts that made this inside floor.

Don't work much with Meshmixer because modifies with this tools sometimes makes more work.

But as you've spent much work in order to have this ring inserted, I'll think you better have your model as you've modify it..  As there was only parts of four layers that has to be removed, I did just that. I'm a big fan of NC Viewer (v1.13), that's really nice to use as it can work with many code types. Together with Notepad++ (v7.9), a standard Notepad in windows and of cause with Cura 4.7.1 you can do pretty much..  As Notepad++ and NC Viewer have same reference showing the gcode just the same, is a must..

When modifying in NC Viewer, you MUST store the changes immediately after change. If not, NC Viewer will fill inn the missing parts when you start analysis of the object.

 

Here is how I did it:

Last cmd (command) in your gcode file, just before starting printing one yellow ring with infill.
This you can see in Cura when viewing (play) gcode file from layer 25.

 

1/26-30895, meaning start of gcode part that's making the top layer filled inside your object.
2/26-31179, meaning stop of the above gcode part -including this line..

 

The print head return to same point it moved from, to make the first infill top of the four
individual that's contain the gcode parts to be removed from the actual layers.

There is four layer to modified by removing this "inserted" infilled "bottom", as pr. Cura def.

NOTE WELL:  WHEN REMOVING CODE PARTS IN HERE, YOU MUST START AT THE LO END FIRST.

IE. FROM LINE NUMBER 35289 TO 34998 (IN LAYER NUMBER 29), THEN 28 AND SO ON.

 

This is because all numbers references below will change, but not the one above.

This reference numbers is only valid for your gcode file; "CE3_Tree_per_model.gcode", before modification!
After modification I named the file; "CE3_Tree_per_model_Mode_1.gcode" (Both files are included in the zip file).

 

;Generated with Cura_SteamEngine 4.7.1 and ; Ender 3 Custom Start G-code

-----------------------------Lines above here must not be changed---------------------------
        30894 G1 X114.7 Y159.349 E1746.09387  ;  Layer on tree before first circle and infill.
1/26-30895 G1 F2700 E1741.09316  ; Start of first layer (1/26) with (1) circle and infill.
-----------------------------Lines in between here to be deleted-----------------------------------ok
2/26-31179 G1 F300 Z5.4 ; Finished first layer part with a circle (1) and infill.
        31181 G0 F9000 X114.172 Y158.814 Z5.4; Next continued layer after removal of first infill.

 

-----------------------------Lines in between here must not be changed------------------------

 

        32258 G1 X114.47 Y159.256 E1882.41152 ; Layer on tree before second circle and infill.
1/27-32259 G1 G1 F2700 E1877.41152 ;  Start of second layer (1/27) with (1) circle and infill.
-----------------------------Lines in between here to be deleted-----------------------------------ok
2/27-32552 G1 F300 Z5.6 ; Finished second layer part with a circle (1) and infill.
        32554 G0 F9000 X113.942 Y158.721 Z5.6 ;  Next continued layer after removal of second infill.

 

-----------------------------Lines in between here must not be changed------------------------

 

        33635 G1 X114.24 Y159.163 E2018.68156  ;  Layer on tree before third circle and infill.
1/28-33636 G1 F2700 E2013.68156 ; Start of third layer (1/28) with (1) circle and infill.
-----------------------------Lines in between here to be deleted-----------------------------------ok
2/28-33919 G1 F300 Z5.8 ;  Finished third layer part with a circle (1) and infill.
        33921 G0 F9000 X113.713 Y158.627 Z5.8  ; Next continued layer after removal of third infill.

 

-----------------------------Lines in between here must not be changed------------------------

 

        34997 G1 X114.01 Y159.069 E2154.837  ; Layer on tree before fourth circle and infill.
1/29-34998 G1 F2700 E2149.837 ; Start of fourth layer (1/29) with (1) circle and infill.
-----------------------------Lines in between here to be deleted-----------------------------------ok
2/29-35289 G1 F300 Z6 ;  Finished fourth layer part with a circle (1) and infill.
        35291 G0 F9000 X113.489 Y158.535 Z6 ; Next continued layer after removal of third infill.
-----------------------------Lines under here must not be changed---------------------------------

 

 

When I converted your project file I got a big gcode file (had to be zipped). 🙂

CE3_Tree_per_model_z.zip

 

Just check the slicing yourself and see if there is not anything wrong or missing.

 

Hope this help

Good Luck

 

Thanks

Torgeir

 

 

 

 

Edited October 9, 2020 by Torgeir
Text error.

[Torgeir 264]

Forgot this one..

 

 

Torgeir