Auto-assembled, not yet reviewed

Thor

DIY 3D-printable 6-DoF robotic arm driven by stepper motors.

Reproducibility80/100Strong source coverage, unverifiedCADBOMWIREFWBUILDLICREPHow it is computed
Thor open-source 6-DoF robot arm, 3D render from thor.urdf.xacro
full robot 3D · thor.urdf.xacro

About Thor

Thor is an open-source, 3D-printed 6-DoF robotic arm by AngelLM. The README describes a 625 mm tall yaw-roll-roll-yaw-roll-yaw manipulator with up to 750 g payload, FreeCAD source, printable STL files, STEP exports, official assembly/electronics/firmware docs, and links to ThorControlPCB, Asgard and Thor-ROS. The 3D view comes from the Thor-ROS arm description (Xacro and DAE meshes) linked from the README.

Licenses

Hardware
CC-BY-SA-4.0
Software
CC-BY-SA-4.0
Docs
Not published

Degrees of freedom

6 DoF arm 6

Breakdown source

Serial armsource

How to build Thor

5 steps

Steps marked Motari summary condense the linked source; follow the source for exact instructions. Upstream step marks a step taken from the linked guide.

  1. Review official docs

    Start from the Thor documentation index, BOM, 3D printing guide, assembly guide, electronics guide and firmware guide.

    Upstream stepthor.angel-lm.com/documentation

  2. Print the parts

    Print the STL set from the repository using the documented filament classes and official 3D printing guidance.

    Motari summarythor.angel-lm.com/documentation

  3. Assemble joints and transmissions

    Build the six articulations with the printed gears, GT2 belts, pulleys, shafts, bearings, balls and fastener assortment listed in the official BOM.

    Motari summarythor.angel-lm.com/documentation

  4. Choose and wire electronics

    Use the open-source Thor ControlPCB/Arduino Mega path or a documented commercial controller alternative such as Fly Super8 Pro, following the wiring guide.

    Upstream stepthor.angel-lm.com/documentation/electronics

  5. Install firmware and control software

    Configure GRBL or RRF as documented, then use Asgard or the ROS2 integration for motion/control workflows.

    Motari summarythor.angel-lm.com/documentation
Print time200 h
Assembly time10 h

Wiring, power and firmware are safety-relevant and shown for reference only. Check them against the source before building.

Thor bill of materials

16 rows

Cost to build

€350EURsource total
  • hardware components, excluding the 3D printer€350source total

In the source currency, as read on 2026-09-30. Not converted, and not checked against current vendor prices: none of these is a Motari-verified checkout total.

Thor parts, as the source lists them (read 2026-09-30). Prices are the source's, not checked against vendors.

Thor bill of materials
PartQtySpecSourceConfidence
Filamentprinted structural parts
13-4 kg PLA/PETG plus 0.5 kg ABS listed on official BOM page
suppliers from the project's BOMprice not listedOfficial BOM page lists filament material quantities; README line 61 directs builders to print the STL files
high
Stepper motorsjoint actuators
71x 40 mm 40 N.cm, 3x 34 mm 121.2 N.cm with 5:1 reduction, 3x 34 mm 26 N.cm
StepperOnline / AliExpress, as the project's BOM listsprice not listedOfficial BOM page Stepper Motors table; README lines 75 and 62 identify stepper motors and BOM
high
MG995 servomotortool/end-effector servo
1MG995
AliExpress, as the project's BOM listsprice not listedOfficial BOM page Servomotors table lists 1x MG995
high
GT2 beltsbelt transmissions
32x closed GT2 208 mm/104 teeth/6 mm, 1x open GT2 1000 mm/6 mm
AliExpress, as the project's BOM listsprice not listedOfficial BOM page GT2 Belts table; README line 77 identifies GT2 pulleys and belts
high
GT2 pulleystransmission pulleys
53x 20-tooth 5 mm bore, 2x 40-tooth 5 mm bore
AliExpress, as the project's BOM listsprice not listedOfficial BOM page GT2 Pulleys table
high
Bearings and 6 mm ballsjoint bearings
11x 16014zz, 11x 625ZZ, 2x MF84ZZ, 30-40 plastic or metal balls 6 mm
AliExpress, as the project's BOM listsprice not listedOfficial BOM page Bearings table
high
Shaftsjoint shafts
62x 14x4 mm, 1x 14.5x5 mm, 1x 32x5 mm, 1x 102x5 mm, 1x 128x5 mm
AliExpress, as the project's BOM listsprice not listedOfficial BOM page Shafts table
high
Screws assortmentmechanical fasteners
1M2 and M3 screws including 60x M3x8, 35x M3x12, 37x M3x16, 16x M3x25 and other sizes
suppliers from the project's BOMprice not listedOfficial BOM page Screws table
high
Thor ControlPCB or compatible controller boardstepper control electronics
1open-source Thor ControlPCB Arduino Mega shield or Fly Super8 Pro alternative
make yourself / PCBWay / commercial boardprice not listedREADME lines 53 and 76 plus official electronics page describe ThorControlPCB and commercial board options
high
Arduino Mega / controller electronicscontrol board host for Thor ControlPCB option
1Arduino Mega shield architecture with up to 8 stepper outputs
generic / from the project's BOMprice not listedOfficial electronics page describes Thor ControlPCB as an Arduino shield and the earlier Arduino Mega/RAMPS approach
med
A4988 stepper motor driverStepper drivers for the Thor ControlPCB
8A4988 stepper driver
AliExpress, as the project's BOM listsprice not listedOfficial Thor BOM page (thor.angel-lm.com)
high
Micro endstopListed in the official BOM electronics table
1micro endstop switch
AliExpress, as the project's BOM listsprice not listedOfficial Thor BOM page (thor.angel-lm.com)
high
Optical endstopListed in the official BOM electronics table
4optical endstop
AliExpress, as the project's BOM listsprice not listedOfficial Thor BOM page (thor.angel-lm.com)
high
12V 50 mm fanListed in the official BOM electronics table
412V 50x50x10 mm, 2 wires
AliExpress, as the project's BOM listsprice not listedOfficial Thor BOM page (thor.angel-lm.com)
high
12V 40 mm fanListed in the official BOM electronics table
712V 40x40x10 mm, 2 wires
AliExpress, as the project's BOM listsprice not listedOfficial Thor BOM page (thor.angel-lm.com)
high
DC jack, on/off and reset buttonsListed in the official BOM electronics table
1DC jack plus 16 mm on/off and reset buttons
AliExpress, as the project's BOM listsprice not listedOfficial Thor BOM page (thor.angel-lm.com)
high

Rows from the source's own parts list 19

README.md@286b081markdown

Source rowQtyPrice and vendorLine
hardware cost below 350 EUR
vendor not listedbelow 350 EUR source claim
L38
FreeCAD source directory
vendor not listedno price listed
L45
printable STL directory
vendor not listedno price listed
L47
STEP directory
vendor not listedno price listed
L48
Thor-ROS related repository
Thor-ROSgithub.comno price listed
L52
ThorControlPCB related repository
ThorControlPCBgithub.comno price listed
L53
Asgard control software repository
Asgardgithub.comno price listed
L54
official documentation index
thor.angel-lm.com/documentationthor.angel-lm.comno price listed
L60

11 more rows in README.md

Thor source files

8 files

Files stay in the upstream repository under their own licenses; these links open them there. The 3D model on this page is Motari's conversion of the file named under Simulation.

Thor in simulation

Robot description files a simulator or CAD tool can load, linked at the commit they were found.

The 3D specimen on this page is converted from ws_thor/src/thor_urdf/urdf/thor.urdf.xacro at e11a56b.

Builds of Thor

0 reviewed

No reviewed builds of Thor yet.

A build log records the evidence (photos, a video, your repository), what the build cost, how long it took and what you changed. Each one is checked by Motari (until a maintainer claims this page) before it shows here, and reviewed builds count toward the reproducibility score.

Sources and provenance

Sources

Last push to AngelLM/Thor: 2025-05-09 (checked 2026-10-01)

Related links

How this page was made

Assembled from public sources on 2026-06-04, not yet reviewed by the maintainer. Each figure links to where it is stated; a value the sources do not state reads "not published". Last source review: official docs reviewed; vendor total not reconciled.

Original files stay intact and separately licensed; Motari adds only the summary on this page. Maintainer? Request a correction or removal.

Badge for the README

Maintain Thor? Show its reproducibility score in the project's README. The badge links back to this page and updates with the score.

Badge: reproducibility 80/100

Markdown
[![Motari reproducibility score for Thor](https://motari.io/api/v1/badge/thor-arm)](https://motari.io/r/thor-arm)
HTML
<a href="https://motari.io/r/thor-arm"><img src="https://motari.io/api/v1/badge/thor-arm" alt="Motari reproducibility score for Thor" height="20"></a>

Not fully met yet: bom evidence (partial). The score is read from the project's own sources, so publishing what is missing is what raises it. A score of 90 or more needs a reviewed build. How the score is computed