Pen Plotter ESP32

This is a simple 3d printed pen plotter that broadcasts a wifi network with web server that fully houses the whole interface. So anyone with wifi and web browser can use the device.

The plotter runs custom firmware on an ESP32 and serves up a simple MS Paint-style web interface. A lightweight custom firmware directly controls three 28BYJ-48 stepper motors through ULN2003 drivers. The entire web interface is embedded in the ESP32's flash memory - no SPIFFS, no external files. The firmware includes a simple G-code parser that handles the basics. Touch-friendly controls let you test motors, home axes, and manually raise/lower the pen.

The total cost is under $20 with 3d printed chassis. Perfect if you want a simple WiFi plotter without the complexity of full CNC firmware.

You need one of everything, and multiples of the following:

• 2 x gear.stl

• 3 x x_frame_spacer.stl

• 9 x electronics_mount_spacer.stl

The only parts that need support are the x_frame.stl and y_frame.stl along the interior of the rail where the x_movement.stl and y_movement.stl slide within the frames.  Snug supports were easiest to remove by running a small flathead screwdriver down the rail. See the image below for an example of supports.

This can be printed on a Prusa Mini but the x_frame.stl needs tipped on edge to fit.

Complete project details at Hackaday.

Video demo at TikTok or Youtube.

This project is a combination of original parts and parts from other sources.