Open Source Side Project

OpenBot

MakerBot ended support for MakerBot Print and MakerBot Desktop on the Replicator+, leaving working printers stranded. OpenBot replaces that software: it slices models, sends them to the printer over the network, streams its camera, and manages its Wi-Fi — and drives Creality Ender-3 printers over USB or SD card, too. Free and open source, under Lighthouse Consulting.

GPL-3.0-or-later Python + PySide6 macOS · Raspberry Pi 95+ tests

View on GitHub ↗ Download for Mac ↗

What it does

One app, two printer families.

The same app adapts to whichever printer is connected — full network control and slicing for the MakerBot Replicator+, and USB/G-code control for the Ender-3 family.

	MakerBot Replicator+	Creality Ender-3 family
Slicing	STL/OBJ → .makerbot, with the bundled OrcaSlicer engine	STL/OBJ → G-code, using Creality's own OrcaSlicer profiles
Build plate	Several objects at once: drag in 3D to move, rotate, scale, duplicate, auto-arrange
Connection	Network, encrypted with a pinned certificate and one-time knob-press pairing	USB (Marlin), checksummed lines with automatic resend
Printing	Upload & print, pause/resume/cancel	Print over USB, or save to an SD card (FAT32 check, safe names, eject)
Camera	Live view, snapshots, a photo of each finished print	—
Printer settings	Wi-Fi scan/join/forget, static IP or DHCP, rename	G-code console, preheat, home, emergency stop
Safety	Build-volume and temperature checks on every file	PTFE-safe temperature limits for the stock hotend (240°C)

It can also share any of these printers with every Mac in the house, or run headless on a Raspberry Pi next to the printer — other Macs join with a 6-digit pairing code and a role (Viewer, Operator or Admin), and every server has its own web page at https://<server>:8765/ for phones and tablets.

Screenshots

The desktop app.

OpenBot Printers page listing discovered network printers, plus USB and OpenBot-server connection options — **Printers** Discover Replicator+ printers over Bonjour, connect an Ender-3 over USB, or find another OpenBot server on the network.

OpenBot Prepare page showing a 3D build plate viewer and print settings for material, quality, infill and supports — **Prepare** Arrange models on the build plate in 3D, tune material, quality and infill, then slice with the bundled OrcaSlicer engine.

OpenBot Monitor page with print progress, hotend and filament stats, and a live camera panel — **Monitor** Track progress, extruder and nozzle stats, and watch the printer's camera live while a job runs.

OpenBot Share page for approving other devices to access a shared printer with Viewer, Operator or Admin roles — **Share** Share a connected printer with the rest of the house — approve devices with a pairing code and assign a role.

Under the hood

Built from a reverse-engineered protocol.

Reverse-engineered protocol

MakerBot's network protocol was never public — connecting to the Replicator+ meant working it out from scratch, then pinning its certificate for every future connection.

Marlin over USB

Checksummed G-code lines with automatic resend for the Ender-3 family, plus temperature limits tuned to the stock hotend's PTFE liner.

Server mode

A lightweight server shares one printer with a whole house — pairing codes, per-device roles, and a shared print queue that waits for the plate to be confirmed clear.

Cross-platform packaging

A signed, notarized universal2 .dmg for Intel and Apple Silicon Macs, and a Debian package for a headless Raspberry Pi server.

Get OpenBot

Free software, built to keep printers out of the landfill.

OpenBot is free under the GNU GPL v3. The source, build instructions and releases are on GitHub.

github.com/dalerks/openbot ↗