Core One Pen Plotter - Remix

I've made a few updates to the great plotter model to reduce some of the hardware requirements and make it easier to add/remove from the printer. In addition, I added a few tabs to ensure proper routing of the rubber band to ensure it does not get caught under the pen holder, as well as slightly enlarged the pen holder opening to support Milwaukee Inkzall pens that I've been using with some success when experimenting with plotter conversions in the past.

Key Updates

1. The main body now has hooks for the rubber band placement, instead of requiring 2 M3 bolts and nuts

2. The pen plotter piece

   1. Has tabs to guide the routing of the rubber band

   2. Integrated rubber band tension point as opposed to using the pen set-screw

   3. Slightly larger opening for Milwaukee Inkzall

3. I've included some thumbscrew models based on an existing model to make it easier to add/remove the unit from the Nextruder, as well as tighten the pen holder.

G-Code Updates

Nothing major here, I just replaced the "Pause" with a 10 second countdown when removing the pen spacer to speed up the time.

Setup Process

The original instructions are absolutely excellent for using Inkscape and the Community Laser tool so just follow those. For installing the pen, I've found that after the Core One performs auto-homing, it sets the Z-axis to 2mm, which is exactly where we want the pen height. So my setup process is:

Pen Installation

1. Auto-Home the printer with plotter installed but without pen

2. Place a scrap sheet of paper on the print bed to prevent marking your metal sheet

3. Install the pen so that the point rests on the paper. Apply very light pressure and tighten the screws to hold the pen

4. Install the Pen Spacer piece to raise the pen above the level of the nozzle

With this setup, you should see only minimal travel of the pen and will consistently set the height each time.

Plotting Setup

1. Layout paper on desired build sheet. I've used both smooth and satin sheets without problem. Magnets hold the paper better on the slightly textured satin surface.

2. Start the print (gcode generated by Inkscape extension) Make sure you have the pen spacer installed!

3. Printer will auto-home and use the load cell to detect the bed

4. After homing, you will have approximately 10 seconds to remove the spacer. The screen should display "Deploy Pen" with a countdown timer.

5. Let the drawing run, if you see any close calls or crashes, immediately stop the print.

Print Settings

Filament: Overture PETG (Black and Orange)

Layer Height: 0.2mm (Core One STRUCTURAL preset)

Nozzle: 0.4mm

Infill: 10% Adaptive Cubic

Support: For Support Enforcers Only (the attached 3MF has supports painted on)