Amalgam: A 2026 RepRap Reference Specification
High-Mass, Low-Cost, Total Control.
Amalgam is a scavenger-friendly 3D printer built from two donor printers. It replaces the “black-box” appliance philosophy of modern printers with an open, parametric system that adapts to what you scavenged.
“A Tractor with the Brain of a Racecar”
What is Amalgam?
A 3D printer that uses: - Heavy hardware (geared extruder, overbuilt frame) for mechanical stability - Software intelligence (Klipper) for precision and auto-leveling - Scavenged parts to prove high-performance manufacturing from e-waste
| Spec | Target |
|---|---|
| Price | < $300 AUD |
| Build Volume | 220×220×220mm |
| Speed | 70-120mm/s |
| Accuracy | ±0.1mm |
Quick Links
| Document | Description |
|---|---|
| philosophy.md | The “Tractor” philosophy and 20 years of RepRap wisdom |
| ../REFERENCE-SPEC.md | The specific hardware choices (Pitan, E3D V6, etc.) |
| ../BUILDING.md | How to generate STL files from parametric CAD |
| adr/ | Architecture Decision Records |
| guides/ | Build guides |
| deep-dives/ | Design exploration documents |
Frame Paths
Amalgam requires two donor printers. Pick your path based on what you scavenged:
| Path | Frame | Motion | Best Donors | Cost |
|---|---|---|---|---|
| Scaffold | M10 Threaded Rod + MDF | Smooth Rods + LM8UU | Anet A8, Wanhao, Prusa clones | ~$190-230 |
| Mill | Aluminum Extrusion + MDF | V-Slots + POM Wheels | Ender 3, CR-10 | ~$160-185 |
| Lathe | Aluminum Extrusion + MDF | Smooth Rods + IGUS | Ender 3 + bought rods, mixed | ~$235-280 |
All paths share: MDF base (squaring jig + damping), Triple-Z leveling, Pitan extruder + E3D V6 hotend, Klipper firmware.
Optional: Add MKS SKIPR (~$130) for cleaner single-board electronics.
Who is this for?
Build Amalgam if you: - Have two broken/cheap printers to scavenge - Love understanding every bolt and line of code - Want a machine you can repair with hardware store parts - Reject cloud-lock and proprietary ecosystems
Buy an appliance if you: - Want “set-and-forget” out of the box - Don’t enjoy the engineering challenge - Are buying all new parts anyway
Getting Started
- Read the philosophy: philosophy.md
- Understand the hardware: ../REFERENCE-SPEC.md
- Get two donors: Match donor types if possible (two rod-based or two V-slot)
- Run the wizard:
python scripts/wizard.py— it recommends your frame path - Build it: guides/
The Bootstrapping Path
- Get two matching donors - Two Ender 3s, two Anet A8s, etc. (~$100-120 total)
- Print Amalgam parts - Use one donor to manufacture all printed parts
- Tear down both donors - Salvage motors, beds, PSUs, electronics, rods/extrusions
- Assemble Amalgam - MDF base + frame + salvaged organs
- Transcend - Re-print parts on the rigid new frame for higher precision
Community & License
The Amalgam is released under GNU GPL v3, the same license as the original RepRap Darwin.
“You aren’t just building a printer; you’re joining a 20-year conversation about sovereignty.”
For the complete philosophy, see philosophy.md. For the hardware specification, see ../REFERENCE-SPEC.md.