This repository is intended to be a series of FreeCAD versions of jyjbird's 4 axis, polar, "core-RΘ" 3D printer – an entirely new type of multi axis 3D printer designed from the ground up. To start a FreeCAD version of the "original" (f8d197c circa 16 Mar 2025 commit) will be generated. Check out the Wiki for build guides, links to useful sites/videos and other hopefully useful information.
Check out jyjbird's youtube video to see it in action!
A multi axis printer is pretty hopeless without a non-planar slicer, which is why I built this quick radial slicer for the printer. This leverages the printer's rotating nozzle to print simple parts without supports, but there are some limitations to it which I cover in the YouTube video. I'm also working on an optimization based slicer which will be able to print any object without support so stay tuned for that!
There is a wealth of knowledge in the Discussions, Pull Requests and Issues tabs of this repo. The printer is by no means "plug and play", and there are no instructions as of yet, but the information in the discussions should help you get started. Feel free to post questions on the discussions tab.
You can view the 3d model online to see how to assemble the printer. Everything is 3D printable, however I got the extruder mount made out of metal by JLCPCB as there is quite a bit of torque on that part. I've also included the gerber files to make your own PCB buildplate, but a sheet of MDF wood would also work.
Links to Aliexpress stores are included so you know what to get, but they are not neccesarily the best source for your country or build goals. Click thumbnails to expand. * indicates alternates.
| Component | Qty | Function | Source | Store Search Hint | Image |
|---|---|---|---|---|---|
| Frame and Linear Motion | |||||
| 2040 T-Slot Extrusion 350mm | 1 | Frame Vertical | Aliexpress Magic Dragon | Select Products > Aluminum Extrusion |  |
| 2040 T-Slot Extrusion 100mm | 1 | Frame Horizontal | Aliexpress Magic Dragon | Select Products > Aluminum Extrusion | |
| 2020 T-Slot Extrusion 150mm | 1 | Frame C Axis | Aliexpress Magic Dragon | Select Products > Aluminum Extrusion |  |
| 2020 T-Slot Extrusion 250mm | 1 | X Axis | Aliexpress Magic Dragon | Select Products > Aluminum Extrusion | |
| 2020 T-Slot Corner Bracket | Frame & C Axis | Aliexpress Magic Dragon | Select Products > Aluminum Extrusion, Corner Bracket |  |
|
| MGN9 250mm Linear Guide with MGN9 C Carriage | 1 | X Axis | Aliexpress Magic Dragon | Select Products > Linear Guide>MGN9 |  |
| MGN9 C Carriage | 1 | X Axis additional Linear Carriage | Aliexpress Magic Dragon | Select Products > Linear Guide>MGN9 |  |
| MGN12 250mm Linear Guide with MGN12 H Carriage | 2 | Z Axis | Aliexpress Magic Dragon | Select Products > Linear Guide>MGN12 | |
| Drive | |||||
| NEMA 17 External Linear Stepper Motor 40mm with 300 mm T8*8 Lead Screw | 1 | Z Axis | Aliexpress JooWo | Store Search Linear Stepper Motor Lead Screw |  |
| NEMA 17 External Linear Stepper Motor 40mm with 310 mm T8*8 Lead Screw | 1* | Z Axis *Alternate | Aliexpress Stepperonline | Select Products Linear_Stepper |  |
| T8*8 Lead Screw Nut H Flange | 1 | Z-Axis | Aliexpress Kingroon | Store Search T8 Nut H Flange |  |
| Nema 17 Stepper Motor 34 mm | 3 | XB & C Axes | Aliexpress Stepperonline | Select Products > Open Loop Motor |  |
| GT2 Timing Belt Loop 400mm | 1 | C Axis | Aliexpress ZHong Trans | Select Products > Timing Belt |  |
| GT2 Timing Belt Loop |
1* | C Axis *Alternate | Aliexpress ZHong Trans | Select Products > Timing Belt | |
| GT2 Timing Belt Loop 752 mm | 1 | XB Axes | Aliexpress ZHong Trans | Select Products > Timing Belt | |
| GT2 Timing Belt Loop |
1* | XB Axes *Alternate | Aliexpress ZHong Trans | Select Products > Timing Belt | |
| GT2 Timing Pulley 40Tooth, Type AF 6 mm Belt, 5 mm Bore ≤ 11.3 mm | 1 | B Axis | Aliexpress ZHong Trans | Select Products > 2GT Pulley |  |
| GT2 Timing Pulley 16Tooth, Type KF, 6 mm Belt, 5 mm* Bore | 3 | XB & C Axes | Aliexpress ZHong Trans | Select Products > 2GT Pulley |  |
| GT2 Timing Pulley 16Tooth, Type AF 6 mm Belt, 5 mm Bore ≤ 11.3 mm | C Axis *Alternate to mount bed directly without springs | Aliexpress Mulge | Select Products > 2GT Pulley | ||
| GT2 Idler 16T w/ Teeth, 6 mm Belt, 3 mm Bore | 3 | XB Axes | Aliexpress ZHong Trans | Select Products > 2GT Pulley |  |
| GT2 Idler 16T w/o Teeth, 6 mm Belt, 3 mm Bore | 4 | XB Axes | Aliexpress ZHong Trans | Select Products > 2GT Pulley |  |
| Electronics | |||||
| The Core-Rθ printer requires 5 Axes and currently its kinematics are only supported by RepRapFirmware (RRF) | See Team Gloomy Supported Board List for lower cost alternates to Duet 3D control boards | ||||
| Fly E3 Pro Ultra | 1 | 5-Axis RRF Control Board | Aliexpress Mellow 3D | Select Products > Fly Electronic Board |  |
| Fly Super 5 Pro | 1* | 5-Axis RRF Control Board *Alternate | Aliexpress Mellow 3D | Select Products > Fly Electronic Board |  |
| Duet 3D Mini 5+ | 1* | 5-Axis RRF Control Board *Alternate | Duet 3D | Select Products |  |
| Micro SD Card ≤32GB, Speed ≥Class 4 | ≥1 | Required for WiFi/headless Team Gloomy recommends 8GB | Aliexpress MicroStick | Select Products > Memory Card > Microdata |  |
| 24V 10A Power Brick | 1 | Motion control & air pump | Aliexpress Shop5496179 | Select Products > Adapters > AC-DC Adapters |  |
| 5.5x2.5 mm Female Jack Panel Mount | 1 | Control board enclosure | Aliexpress Javino | Select Products > Connector...> DC Plug & Socket |  |
| 5.5x2.5 mm Jack Set | 1* | Control board enclosure *Alternate for non brick supply | Aliexpress Javino | Select Products > Connector...> DC Plug & Socket |  |
| 18-28 AWG Wire | 1 | General | Aliexpress Javino | Select Products > Tools... |  |
| Limit Switch, Generic | 1 | Bed Z Probe | Aliexpress Kingroon | Store Search Endstop Mechanical Limit Switch |  |
| Limit Switch Omron SS-5-2 | 1* | Bed Z Probe *Alterate | Electronics supplier | Store Search SS-5-2 |  |
| 4010 24 V Fan | 2 | Control Board Cooling | Aliexpress STC Cooling | Select Products > DC Fan > 40 mm |  |
| Quick Connect Set 2.8 4.8 6.3 mm | 1 | Limit switch & misc | Aliexpress Daevkaema | Select Products > Terminal & Connector |  |
| Heat Shrink Tubing Set | 1 | General | Aliexpress Daevkaema | Select Products > Heat Shrinkable |  |
| JST-PH Terminal Crimping Pliers | 1 | Control Board Connections | Aliexpress IWISS Tools | Store Search JST-PH |  |
| Printing Components | |||||
| BIQU H2 V2S Extruder | 1 | Joy & Anguish | Aliexpress Big Tree Tech | Select Products > H2S Extruder... |  |
| Airbrush Nozzle Adapter | ≥1 | Lengthen nozzle reach for non-planar! Spares recommended | Aliexpress 5A Plus | Search Store Airbrush Nozzle Adaptor |  |
| Print Bed 250 mm Dia Self Made | 1 | Print Bed | Light, stiff material | 3x3 mm Countersunk holes on 150 mm dia circle | |
| Print Bed 250 mm Dia | 1* | Aluminum Print Bed *Alternate |
|
||
| Print Bed 250 mm Dia | 1* | PCB Print Bed *Alternate | JLCPCB | pcb buildplate |  |
| Print Bed ~ |
1* | Print Bed *Alternate | |||
| Micro Vacuum Pump 24V | 1 | Part cooling | Aliexpress Hua02 | Search Store Micro Vacuum Pump |  |
| Silicone Tubing 6 mm ID x 8 mm OD | 1-5 m | Part Cooling | Aliexpress First Met | Store Search Silicone Hose |  |
| Filament Spool Holder | 1 | Aliexpress 5A Plus | Search Store Filament Spool Holder |  |
|
| PTFE Tube 2 mm ID x 8 mm OD | 1 | Aliexpress 5A Plus | Select Products > Teflon Tube |  |
|
| Hardware | |||||
| 2020 T-Slot Sliding Nut M4 | 50 | Frame | Aliexpress Magic Dragon | Store Search Sliding Nut |  |
| 2020 T-Slot Sliding Nut M3 | 50 | Linear Guides | Aliexpress Magic Dragon | Store Search Sliding Nut | |
| M4 Screw Set | 1 | Frame | Aliexpress Wzhuida | Store Search M4 Metric Screw Assortment Hex Socket Head Cap |  |
| M3 Socket Head Cap Screw Set, include 40 mm | 1 | Linear Guides & General | Aliexpress Wzhuida | Store Search M3 Screw Assortment, M3x6-50mm |  |
| M3 Flat Head Screw DIN7991, include 2x20 mm, 3x25 mm | 1 | Extruder & Bed Mounts | Aliexpress Wzhuida | Store Search Flat Head Screw |  |
| M3 Square Nut DIN562 | 50 | General | Aliexpress Liya Hardware | Store Search DIN562 Thin Nut |  |
| M3 Hex Nut DIN985 | 5 | Bed Mount & C Axis Tension | Aliexpress Wzhuida | Store Search DIN985 |  |
| 5x20x0.5-1.0 mm Compression Spring | 3 | Bed Mount | Aliexpress Zrui | Store Search Micro Small Compression Spring |  |
| MR85ZZ 5x8x2.5 mm Bearing | 4 | B axis | Aliexpress Magic Dragon | Store Search MR85ZZ |  |
| MR85ZZ 5x8x2.5 mm ABEC-9 Bearing | 4* | B axis *Alternate | Aliexpress APE Official | Store Search MR85ZZ |  |
| 6810ZZ 50x65x7 mm Bearing | 2 | C axis | Aliexpress Kandle | Search Store 6810ZZ |  |
| 6810ZZ 50x65x7 mm ABEC-9 Bearing | 2* | C axis *Alternate | Aliexpress Shop1104... | Search Store 6810ZZ |  |
| 5x50 mm Cylindrical Pin or Rod | 1 | B axis shaft | Aliexpress YMAX | Search Store Cylindrical Pins for DIY |  |
| 5x11x6 mm Shaft Collar | 1 | B axis | Aliexpress JZN | Store Search SCCAW |  |
| 12x8x9H x 3D mm Rubber Foot | 1 | Frame | Aliexpress TonKing | Store Search Small Shock |  |
| 17x13x14H x 3D mm Rubber Foot | 3 | Frame | Aliexpress TonKing | Store Search Small Shock |  |
Bibtex Citation:
@software{Bird_Core_R-Theta_Printer,
author = {Bird, Joshua},
license = {View repository for custom license.},
title = {{Core R-Theta Printer}},
url = {https://github.com/jyjblrd/Core-R-Theta-4-Axis-Printer}
}