Upload your custom .ttf or .otf font file:
Print the calibration box (15cm x 15cm) first. Then, measure the physical distances on your paper with a ruler and fill them in below to automatically align the layout.
M290 Z... babystep commands via OctoPrint to save the pen tip live!
First 3 words are printing at 10% speed. Micro-adjust Y-position and Z-depth to align perfectly with the paper lines!
Align your paper perfectly on the bed. Jog the printer to target 3 reference points (forms a perfect parallelogram) or all 4 reference points (enables bilinear warping) on your paper, then save their physical coordinates.
Select Character to Draw
Each block displays the status of drawn variants (V1, V2, V3).
Uppercase
Lowercase
Numbers & Symbols
â Add Custom Character
// No G-code generated yet. Click "Generate Plotter G-Code" on the left panel.
đ Mounting & Calibration Guide
How to reliably convert your Anycubic FDM printer into a fully functional handwriting plotter without damaging the heatbed.
â ī¸ OctoPrint Alert: "Invalid mesh / Failed to enable Bed Leveling"
If your print stops immediately with an emergency stop command (M112) stating Failed to enable Bed Leveling, it means your Kobra Neo's internal memory (EEPROM) does not currently hold a valid bed mesh.
To resolve this error instantly:
- Instant Bypass (Recommended): Uncheck the "Enable Bed Mesh (M420 S1)" checkbox under Step 5 on the left panel, then re-generate the G-Code. This completely skips the leveling check and lets your plot proceed immediately.
- Precision Plotting Option: Perform the "Auto Bed Leveling" procedure directly from your printer's LCD control panel, and ensure you save/store settings to the EEPROM afterward. This establishes a valid mesh so the printer can execute
M420 S1without crashing.
1. Hardware Pen Setup
- Spring-loaded Mount: Highly recommended. If the Z-axis drops slightly too much, a solid mount can bend the pen or dent your bed. A spring-loaded mount absorbs height differences.
- Zip-tie/Tape Hack: You can mount the pen to the side of your extruder housing using zip ties or electrical tape. Ensure the pen tip hangs lower than the nozzle by about 10-15mm to avoid hotend collisions.
2. Securing the Paper
- Clean your magnetic PEI bed so tape adheres well.
- Center your lined paper onto the bed. Since A4 is 297mm long, let the extra overflow front and back. Make sure the paper doesn't catch on the printer frame during Y-axis movements!
- Tape all four edges tightly using masking tape or blue painters tape. Keep it completely flat.
3. Zeroing the Z-Axis (Crucial Step)
To print correctly, your printer must know exactly where the pen tip touches the paper surface.
- Ensure the pen is mounted securely.
- Using your printer control screen, home all axes (
G28). Keep your hand on the power switch in case the pen hits the bed! - Slowly lower the Z-axis manually to
Z = 0.0. - Adjust your pen mount physically (or use the baby-stepping/Z-offset screen menu) until the pen tip **just touches** the paper with a tiny bit of pressure.
- Your
Z=0.2height configured in the settings represents this contact point.
đ How to align with Notebook Lines perfectly
No notebook paper is perfectly straight when taped down. Use the Line Alignment G-code button on the left panel first. It generates a quick G-code file that draws single straight lines corresponding to the top and bottom lines of your text block. Watch where the pen draws, adjust your physical paper position, and restart until it perfectly follows your paper lines!
đĄī¸ How to Save the Pen Tip (Crucial Plotter Tips)
A rigid mount is risky: if Z drops slightly too low, the tip will bend, break, or tear the paper. Follow these safety tips:
- Use a Gravity Slider or Spring-loaded Pen Mount: The gold standard. Build or print a mount where the pen is loose inside a vertical slide, held down only by gravity (a couple of washers/nuts for weight) or a light spring. When the Z-axis lowers, the pen makes gentle contact and slides up rather than crushing the tip!
- Babystepping during USB Printing (OctoPrint): Marlin disables LCD tuning menus during host USB prints on some firmware. Use the Live Z-Offset (USB Babystepping) widget under Step 6 in the browser! Clicking these buttons will inject Marlin
M290commands to raise/lower the pen by 0.05mm increments on the fly! - Dry Run Alignment first: Always run the "Run 10s Alignment Verification (Dry Run)" sequence before printing. The pen stays safely raised at all times while moving to check if the path lines up.