This is an upgrade and current release of the conductive ink 3d printer modifications previously posted

Included here are the parts needed to modify a Creality Ender 3 pro FFF plotter to be able to print traces or other graphics using pens or markers on top of or between extruded materials. The Cura post process script, is originally intended for use with this set up, but robust enough to be adapted to other similar configurations or printers.

The first of three parts is the tool holder, it is a set of two tubes that fits on the extruder carriage, the second part is a boot to hold the Pen or marker, it is designed to float up and down the tool holder tube, and the third part is the cradle to hold the tool holder out of the way when not in use.

The tool holder is designed with two screw together parts per tube, intended to work with the shape of the pen holder, with a cone shape at the top and bottom, these along with adjusting the z height, allow you to adjust the tilt of the pen or marker tip when writing. This is the same as the previous release but with the BLtouch shelf lowered closer to the bed.

The updated Pen or marker boot has three screw together parts, intended to allow for holding the pen or marker snugly between the two, top clip and the cradle spacer, parts and allowing the third shaft part to be removed independently when not being used (to be able to replace cap or tip cover when not loaded in printer). This third part has a fixed distance between the top and bottom cones, and a fixed width, to fit into the adjusted tool holder when writing.

The tool cradle has been redesigned to fit tightly to the printer using three specifically designed T-shaped bolts that slide into the groves of the printer frame. The tool holder has also been redesigned with a thicker shelf to hold the Pen or marker holder, without sagging or miss aligning over time. Installation has been updated. It may seem a little like a puzzle box, to assemble, screw the upper T-shaped bolt into the cradle body hole so the T-shaped side is in the same direction and lines up with the grooved upper printer bar slot, screw the two lower T-shaped bolts into the two lower holes to the same depth as the upper T-shaped bolt, aligning the T-shaped side to fit the vertical slot opening. Sliding the cradle into place across the top printer bar to align with the open slot of the upright printer bar, it should be loose enough to tilt outward slightly until the two lower T-shaped bolts can slip into the upright printer bar slots. Once in place, turn the upper T-shaped bolt so that the T part locks the cradle to the printer. turn the lower T-shaped bolts to lock the cradle to the upright bar of the printer, place a pen boot in the cradle and turn the center T-shaped bolt to adjust the tilt of the cradle so the boot aligns with the holder opening and allows the holder to ride up around the boot without binding. Make note of the XY location and height to be used when entering the load and unload programs.

The Cura script “Inserting Gerber data at layer change.py” was designed to emulate similar software with several different input options, being a work in progress, help and suggestions with it are welcome.

The script is intended to work within the scope of the existing program limitations. The Cura program itself is dynamic in variation.  Used with windows and version 4.12 and 5.5 of Cura successfully, other variations may not be as compatible. Please post any corrections or modifications found or needed. 

installing the script for use varies with installation, generally the file needs to be copied to the subfolder of the current Cura program under \plugins\PostProcessingPlugin\scripts\ in some cases of newer Cura installations also require a second copy be placed in the user subfolder under \AppData\Roaming\cura\plugins\

setup the script before placing the part on your table , located within the Cura program under Extensions, Post Processing, Modify G-codes, Add Script section.

The first option is to include debug information in the output file, in most cases these are not required to print.

The second option is to select the number of the sliced layer to print on top of.

The third option is to indicate the single line width the pen or marker will be creating (used in calculating circular fill patterns).

The forth option is to set the speed the pen will be printing.

The fifth option is to indicate the existing tool to get information from, OR, to indicate the distance the extruder head should rise when traveling between printed points, depending on type of tooling input selected.

The sixth option is to indicate the full path and file name of the Gerber (RS274X) file to use as printed pen path, this file must currently be limited to traces and flashed apertures of type circle, square, rectangle, and oblongs. When creating the Gerber data, locate the data so the center is at the same location as the printer bed center, so the data aligns with the extruded data placement, usually at X110Y110mm for a bed size of X220xY220mm by default.

The seventh option is to indicate the type of tooling (loading and unloading) of the printer configuration. The options are,

To use existing tooling, for when the pen tools have been set up as additional extruders,

To enter separate text strings (including several lines and \n for additional newlines within code) ,

To indicate separate text files (with full path and file name),

To skip the tooling step altogether (running over tool path with existing extruder).

here is a sample of load and unload text files for the first and second tool cradle,

; Extruder pen start G-code G90 M104 S0 M109 S0 M221 S0 ; Scale 0 to Deactivate Extruder solenoids M18 E ; Disable Extruder Stepper M84 E ; also Disable Extruder Stepper ; Pen load M117 loading pen 1 G1 F1200 X27.3 Y225 Z60 ; move pen holder under cradle G1 F600 Z164.0 ; move to pick up pen G1 F500 Z170.0 ; move to clear cradle push G1 X80 ; move picked up pen to clear cradle G1 Z60 ; move down to clear cradle M117 pen 1 loaded ; end of pen load G91 G1 X41.5 Y3.2 Z6.8 F1500 ; set pen head offset G90 G92 X80 Y225 Z60 ; re-adjust xyz ; End Extruder start G-code

And

; Extruder pen end G-code G90 G1 F1200 X80 Y225 Z60 G91 G1 X-41.5 Y-3.2 Z-6.8 ; the reverse of the pen head offset G90 G92 X80 Y225 Z60 ; reset zero offset M17 E ; enable extruder stepper ; G92 E0 M221 S100 ; Scale 100 activate extruder solenoid ; first Pen Unload M117 unloading pen 1 G1 F3000 X80 Y225 Z100 F1500 G1 Z170 G1 X27.3 F600 G1 Z60 F600 M117 pen 1 unloaded ; end of first pen unload G1 X0.1 Y230 Z.20 F1500 ; Park head ; End Extruder pen end G-code

then

; start second pen load G-code G90 M104 S0 M109 S0 M221 S0 ; Scale 0 to Deactivate Extruder solenoids M18 E ; Disable Extruder Stepper M84 E ; also Disable Extruder Stepper G1 F1200 X200 Y225 Z60 ; move pen holder under cradle G1 F600 Z170 ; move to pick up pen G1 F500 Z172 ; move to clear cradle push G1 X152 ; move picked up pen to clear cradle G1 Z60 ; move down to clear cradle G91 ; Adjust for extruder offset G1 X-50.75 Y1.2 Z4.5 ; set second pen head offset G90 G92 X152 Y225 Z60 ; reset zero ; End second pen load G-code

and

; start second pen unload G-code G90 G1 F1200 X152 Y225 Z60 ; clear part G1 Z60 G91 ; Readjust for second pen return G1 X50.75 Y-1.2 Z-4.5 ; Reset pen head offset G90 G92 X152 Y225 Z60 ; Reset zero M17 ; enable extruder stepper M221 S100 ; Activate (scale 100) Extruder solenoids ; second pen unload G1 F1200 X152 ; move pen to clear cradle location G1 F600 Z172 ; move pen up to cradle height G1 X200 ; move carriage to cradle drop position G1 Z60 ; move to drop off pen G90 ; end of second pen unload G-code

Copy the content of each section to a text files or copy into respective locations within the running program script.