Longer Drawing Machine

A pen plotter is a creative upgrade that allows a LONGER FDM 3D printer to work as a computer-controlled drawing machine. By replacing the print head with a pen holder, the printer can draw 2D designs with the precision of a CNC system while keeping its original 3D printing function.

This guide explains how to convert a LONGER FDM 3D printer into a drawing machine and create your own pen plotter.

Note: This modification is not compatible with printers equipped with BL-TOUCH leveling sensors.

Preparing the LONGER 3D Printer

1. Print and Install the Pen Holder

First, download and print the pen holder. IThen install the pen holder by using the two screws located on the left side of the head module. The dual blower module already provides two mounting holes for installing the pen holder.

2. Adjust the Print Bed and Install the Pen

Perform normal bed leveling using the paper method between the nozzle and the glass print bed. After leveling:

• Remove the glass plate
• Replace it with a sheet of paper

Since the paper is thinner than the glass, the nozzle will appear higher from the surface. This is normal.

Insert the pen into the pen holder. The pen tip should lightly touch the paper surface. Secure the pen using the screw on the holder.

3. Test the Drawing Movement

Use a test sheet to check whether the X-axis movement can reach all drawing areas. To avoid filament sensor errors:

• Insert a small piece of filament into the filament sensor
• Disconnect the extruder motor E cable

The printer is now ready for drawing operations.

Preparing Cura Software

1. Add a New Printer Profile

Open Cura and add a printer profile that matches your LONGER printer model. Examples:

• LK4PRO → Select LK4PRO
• LK5PRO → Select LK5PRO

Rename the new printer profile as: Drawing Machine

2. Replace the Start G-code

Replace the Start G-code with the following:

; LONGER Start G-code

G21 ; metric values

G90 ; absolute positioning

M82 ; Set Extruder to Absolute Mode

M107 ; start with the fan off

G92 E0 ; Reset Extruder

G28 ; Home all axes

G1 Z2.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed

3. Import the Drawing Machine Profile

Download and import into Cura this print profile "plotter.curaprofile" for "Drawing Machine". The imported profile allows the printer to work without heating hotend/hotbed and without extruding filament.

Preparing the Drawing File

1. Convert an Image into a 3D File

After choosing a 2D image without background (like this one above in the figure), open the "3D Builder" software preinstalled in Windows 10 (if it was not present, download it from the Windows Store). Then select "Open – Load image" to import the selected image.

2. Set the Model Height

Once the image has been imported into 3D Builder, you can change some settings such as Levels, Smooth, and so on; using these settings, edit the file according to your preferences. Once the editing is complete, select Import Image to get the image converted to 3D file.

At this point, assign to the 3D model aheight "Z" of 0.1 mm; in fact, a drawing can be considered as a 3D model composed of a single layer, therefore assigning a thickness of 0.1 mm then the printer finishes the work after the first layer. When the 3D model is ready, proceed to export, selecting "Save as - . STL".

Drawing Process in Cura

1. Import the Drawing Model

Import the previously created "3D" drawing into Cura. At this point, the design can be made either full or with only the outline.

• a.To make a full drawing, make sure "Top/Bottom Thickness" is set to "1"
• b.To create a blank drawing, with edges only, make sure "Top/Bottom Thickness" is set to "0"

2. Export and Start Drawing

Export the G-code file and start the printing process. The LONGER printer will now work as a drawing machine and create the selected design with a pen. You can download sample models here.

Final Thoughts

Turning a LONGER FDM 3D printer into a drawing machine is a simple way to explore new creative possibilities. With a printed pen holder and the correct software settings, your 3D printer can create precise drawings while keeping its original printing capability.

Try different pens and designs to discover more possibilities with your LONGER printer.