Custom Topographic Poster With Pen Plotting

Hi everyone,

In this Instructable, I will explain how I created a custom poster using the pen plotting technique.

The idea is to represent all the topographic lines of a specific location. In my case, I chose an address in the city of Saint-Étienne, France.

This guide will walk you through the process of generating the topographic lines and plotting them onto paper using a pen plotter. All colors can be easily customized to match your preferences.

Follow the steps below to create your own custom topographic poster!

To make the custom topographic, you need :

Materials :

Gel markers

Paper (A4, A3, or larger depending on the size of your cutting machine)

Required tools :

A cutting machine (In my case a CAMEO 4 Pro)

A computer

Required software :

Silhouette Studio

QGIS with the corresponding DEM (Digital Elevation Model) of your chosen location

QGIS is a free and open-source GIS software for viewing, editing, and analyzing geographic data. It provides powerful tools for mapping, spatial analysis, and data visualization.

Download QGIS: https://qgis.org/download/

In addition to QGIS, you will need a DEM (Digital Elevation Model) file for your chosen location. A DEM is a digital representation of terrain elevation, consisting of a grid of elevation points that allow for the analysis and visualization of landscapes, topography, and geographic features.

To obtain a DEM file, use the OpenTopography plugin in QGIS. Here’s a tutorial on how to install and use the plugin, as well as how to generate an API Key.

Generate the DEM of your specific location :

1. Open the map using OpenStreetMap.
2. Find the location you want to center your design on.
3. Copy the coordinates (located at the bottom of the page). These coordinates will help you center the map at the exact position.
4. Choose your desired scale. For an A4 size poster, I chose 1:50000. (Picture 1)
5. Select the DEM Layer.
6. Go to Raster -> Extraction -> Clip raster by extent.
7. In the "Clipping extent" section, click the "Set to current map canvas extent" button, then click RUN.
8. Select the clipped DEM layer. (Picture 2)

Extract the contour lines :

1. Go to Raster -> Extraction -> Contour.
2. Modify the interval (from 10.00 to 20.00 meters) and click RUN. (Picture 3)

Calculate the 100-meter contour lines :

1. Right-click the new Contour layer and choose Open Attribute Table.
2. Click the Field Calculator button.
3. Create an index for each 100-meter contour line. (Picture 4)
4. Field name: index
5. Expression: IF("ELEV" % 100 = 0, 1, NULL)

Change the display of topographic lines :

1. Double-click on the Contours layer. (Picture 5)
2. In the Symbology menu, change "Single Symbol" to "Categorized."
3. Select index as the value.
4. Click the Classify button.
5. Click Apply.
6. Open all the layers inside the Contours layer. Now, you will have two layers: one for each 20-meter contour line and another for each 100-meter contour line. (Picture 6)

Generating the two DXF files :

1. Select only one of the layers.
2. Go to Project -> Import/Export -> Export Project to DXF.
3. Specify the folder and file name.
4. Select the other layer and repeat steps 2 and 3.

Below is an example of two DXF files for a location in Le Puy-en-Velay, France.

Now it’s time to use the cutting machine as a pen plotter!

Pen plotting with a cutting machine involves replacing the blade with a pen or marker to draw precise vector designs on paper. The machine follows digital paths, making it ideal for intricate line work, such as topographic maps in my case.

Key Settings:

The two most important parameters are speed and force. For the CAMEO 4 Pro, I used:

1. Speed : 1
2. Force : 2

Before plotting your final design, test different settings on a draft to find the optimal speed and force.

Steps:

1. Choose a suitable pen – Gel markers work well as they provide a smooth ink flow during plotting.
2. Define your paper size according to your project.
3. Import one of the two DXF files and position it as desired. In my case, I centered the design on the paper.
4. Load the paper and the marker into the machine.
5. Set the material type, tool, speed, and force in the software.
6. Send the job and wait – For an A4 paper, the process takes around 30 minutes to complete.
7. (Optional) Add extra text – You can use the cutting machine’s software to include details like the city name and geographic coordinates.

I hope you enjoyed following this Instructable !

I'm really happy with the final result. My next goal is to create a 1:100 000 scale version on a 50×70 cm poster.

Have a nice day !