Adapting Eleksdraw cutter plotter with the BREADBOARD-LAMP heating system for extruding wax and custom biomaterials for prototyping paperfluidic diagnostics and CNC textile making

Overview

Wearable Technology Interest Group at DoESLiverpool developed a hybrid open source plotter kit that used existing maker-accessible low cost components, to draw, cut, heat and extrude a range of materials accurately by Computer Numerical Control (CNC). The kit re-uses the approach to low cost Arduino temperature control by Nickel Cadmium wire from the BREADBOARD-LAMP project combined with a 3D printed syringe extruder and stepper motor to extrude wax onto lab grade filter paper for prototyping paper-based diagnostics following research into ‘paper fluidic’ literature (Pal et al., 2017), (Pearce et al., 2016), (Siegel et al., 2010) and (Seok et al., 2017).

Wax heated and extruded along paths made using gcode tools in Inkscape and a simple multi platform serial interface form millifluidic channels in the paper substrate & can be used as a form of CNC batik for textile making . Head swaps out with pen holder to annotate paper while a cutting head completes the paper prototype. Interchangeable glass syringe head means it can accommodate biomaterials from the Materiom cookbook.

This kit attempts to interleave all the practices in the research, microfluidics, fluidic temperature control, rapid prototyping, field diagnostics, CNC, Gcode & Grbl tools and methods of 3Dprinting, biomaterials, 2D plotting and cutting and biological technique.

Notes

Pen plotter work with @JackiePease and anyone else who's interested

Working on an Eleksdraw using the grbl

Both need to have wax attachments based on this Prusa Mod for potentially creating CNC/gcode controlled microfluidics channels and batik patterns.

It may be that if more people from @doesliverpool want to be involved then this repository would be better placed under @doesliverpool

Basic Use

Both need to have wax attachments for potentially creating microfluidics channels and batik patterns.

I've been working on the A3 laser engraver, it now has an attachment to hold a pen using elastic bands (the thicker elastic bands used in by Royal Mail are the best so far).

Here are some notes I've made while setting up the A3 laser engraver. Either I or @cheapjack will sort and/or update these.

evil-mad/axidraw#16 – prevent scaling issues, missing viewBox

and this https://stackoverflow.com/questions/15335926/how-to-use-the-svg-viewbox-attribute includes the following:

"In my humble experience, I've always considered ’s viewbox values as a required image ratio to apply to the width and height values. While defining the >laters just I do with any

Make sure all Inkscape units are in mm Tried to add viewBox to the svg like this:

viewBox has to be after height and width, otherwise it assumes pixels (I think you have to save the svg in Inkscape before doing this)

PATHS BEING REPEATED:

This seems to be an issue with changing from Python2 to Python3: https://inkscape.org/forums/cutplot/path-to-gcode-duplicate-lines-wrong-number-of-passes-workaround/

Hi all The simple and shortest solution is to remove 1 from the following line in the file gcodetools.py. for step in range(0, 1 + int(math.ceil(abs((zs - d) / self.tools[layer][0]["depth step"])))): Well, after editing it should look like this: for step in range(0, int(math.ceil(abs((zs - d) / self.tools[layer][0]["depth step"])))): OR you can just change the cutting order to ‘Pass by Pass’

For p5js file:

This library allows you to save files in generic svg format: https://github.com/zenozeng/p5.js-svg

Once you have your file, open Inkscape and then import the svg (the svg format is d:

(these issues with ViewBox etc. might be resolved by making sure that all the Inkscape units are in mm, and that ViewBox is set in document properties, then importing the svg rather than opening it. THIS NEEDS TO BE TESTED
• In document properties, set the display units and size units to mm and choose the size of paper you want e.g. A3 landscape
• Save the file, quit and edit it with your favourite text editor:
    ◦ The paper size will have changed to mm, but the viewBox is still in px. Change that:
        ▪    version="1.1"
        ▪    width="420mm"
        ▪    height="297mm"
        ▪    viewBox="0 0 1587.4016 1122.5197" → change this to viewBox="0 0 420 297"
        ▪    id="svg14"
• Save file then go back to Inkscape
• Resize the object to the size you want and align it on the paper
• Add a layer: Layer → Add Layer → Layer 1
• Move the object to Layer 1. Select all  then: Layer → Move to Layer → Layer 1
• Save the file

To create gcode:

• Open file in Inkscape
• Choose Extensions → Gcode Tools → Path to GCODE
• Change the cutting order to “Pass By Pass” (this is a simple way to get round an issue with the code: https://inkscape.org/forums/cutplot/path-to-gcode-duplicate-lines-wrong-number-of-passes-workaround/)
• Click “Apply” button
• There will be some error messages, but the program will create a file with .ngc extension in the output folder under your home directory (I think you need to create this directory first)
• Rename the gcode file from output_9999.ngc to required file name e.g. yourfile.ngc
• Open the gcode file with vim and change the following:
Editing the gcode file in vim:

:g/G00 Z5.000000/s//M5/g :g/Z-0.125000/s///g :g/G01 F100.0(Penetrate)/s//M03 S20/g

Maybe add F10000 (does this need G something first) :at the start and change F400 to something faster

• Using your favourite text editor, amend line 46 in simple_stream.py to point to your file e.g. f = open('yourfile.ngc','r'); (or amend simple_stream.py to parameterise the file name…)
• If pen plotter is set up with pen in correct position, you are ready to run the file: type the following: python2 simple_stream.py
• The pen plotter should spring into life…