What A 3D-Printed Robot Arm Costs
Two 3D-printed robot arms publish prices, at the time of writing: Arctos kits start at $231, and the Annin Robotics AR4-MK5 costs $1,888 once the $1,189 combo kit and $699 motor package are added. Arctos says its kits range from essential components to full packages, so $231 is the starting price for that range. A banner on the Arctos site offers the Complete Build Kit Bundle with a 50 euro saving, so check the bundle price there before you set a budget.
The AR4-MK5 totals below add up Annin Robotics' listed prices at the time of writing, in US dollars, before shipping and tax. The Robot Combo Kit starts at $1,189, and the StepperOnline motor, driver and power supply package adds $699, for a total of $1,888. Adding the C.I. Printing set of printed covers and spacers at $299.98 brings the build to $2,187.98, and the $139 Pneumatic Gripper Parts Kit takes it to $2,326.98.
On the AR4-MK5, the $699 motor package costs more than twice the $299.98 printed covers set. Arctos sells its plastic parts and its non-printed parts as separate kits, with the motors, bearings, belts, fasteners, wiring, electronics and power supply in the Hardware Kit. Neither maker publishes filament cost or print time, and Annin Robotics publishes no price for printing the AR4 parts yourself, so budget for your own filament separately.
Arctos Six-Axis Kit
Arctos Robotics sells kits and files to build what it calls "a DIY 3D printed robotic arm", an open source Arduino robot arm with 6 axis movement. The build is sold in the three formats listed below. The site also offers a mobile-robot computer-aided design (CAD) set and an assembly manual. Printing the parts yourself needs a printer with a minimum build volume of 200 x 200 mm, according to Arctos, and the banner at the time of writing says buying Arctos Studio includes the CAD files free.
Arctos offers open-loop and closed-loop builds and lists trade-offs for each. Open-loop is less expensive, easier to control and more robust, but it needs more extensive wiring through the arm. Closed-loop removes skipped steps and gives a cleaner build with no visible external wiring, but Arctos says it costs more, is harder to troubleshoot and is more likely to fail from issues such as reversed polarity. The Arctos CLMD closed-loop driver is for National Electrical Manufacturers Association (NEMA) 17 and NEMA 23 motors and uses field-oriented control with Controller Area Network (CAN) bus.
Arctos lists delivery to the United States through Amazon in about 7 days and worldwide through AliExpress in about 15 days. Arctos Studio is artificial intelligence (AI) robotics software to simulate and control the arm, at web version 1.3 at the time of writing. The firmware is open source and Grbl-based on GitHub, and Arctos lists compatibility with Robot Operating System (ROS), ROS2, Grbl, RoboDK and Matlab/Simulink. Our open-source robots guide covers other open-source projects.
- Hardware Kit: all non-printed components, including motors, bearings, belts, fasteners, wiring, electronics and power supply.
- 3D Printed Kit: all required printed plastic parts, pre-manufactured.
- CAD Files: a Fusion 360 assembly file, STL files, pre-oriented 3MF files and a STEP assembly file for self-printing.
Annin Robotics AR4-MK5
Annin Robotics describes the AR4-MK5 as an "open-source 6-axis arm for a desk" for schools, shops and makers. A builder can machine the aluminum or print the parts, then program the arm in Python or ROS. Annin Robotics lists six degrees of freedom, 24.75 in reach, a 4.15 lb payload and 0.25 mm repeatability. It also lists a mass of 27 lb and power of 198 W.
The AR4 MK5 Robot Combo Kit, from $1,189 at the time of writing, contains the aluminum structure, hardware and primary electronics. Motors are bought separately, and Annin Robotics lists a StepperOnline motor, driver and power supply package at $699, bought at StepperOnline. The add-ons and their prices on the Annin Robotics site are listed below, all in US dollars before shipping and tax.
Annin Robotics lists a Python human-machine interface (HMI), ROS 2 community drivers, Teensy 4.1 kinematics, a digital twin, Modbus, G-code and OpenCV vision in the AR4-MK5 software. Its listed applications include pick and place, machine tending, sorting, welding, document sorting, assembly, scanning, agriculture, camera and chess. Pick the AR4-MK5 if you want an aluminum structure and a published repeatability figure, and can budget at least $1,888 with motors.
- Robot Combo Kit (aluminum structure, hardware, primary electronics): from $1,189
- StepperOnline motor, driver and power supply package: $699
- Pneumatic Gripper Parts Kit: $139
- Printed covers and spacers in black polyethylene terephthalate glycol (PETG), sold by C.I. Printing: $299.98
3D-Printed Robot Arm Specs Side by Side
The two printed arms publish specs in different units, with Arctos in millimetres and kilograms and Annin Robotics in inches and pounds. The table keeps each maker's own figures, so convert the units yourself before you compare reach or payload. Arctos publishes no repeatability figure, so the 0.25 mm AR4-MK5 figure has no Arctos number to set against it.
The price signals in the table cover different things. The $231 Arctos figure is a starting price for a kit range, the AR4-MK5 figure covers the combo kit without motors, and the $275.00 Braccio price excludes the Arduino board. For a like-for-like budget, add the AR4-MK5 motor package to reach $1,888, then check what the Arctos tier you want includes on the Arctos site.
| Arm | Axes | Reach | Payload | Listed price signal | Printing role |
|---|---|---|---|---|---|
| Arctos | 6 | 600 mm | 2 kg | Starting at $231 | Print the parts from CAD files, or buy the pre-made 3D Printed Kit |
| Annin AR4-MK5 | 6 | 24.75 in | 4.15 lb | Combo from $1,189 plus $699 motors | Machine the aluminum or print the parts; printed covers set $299.98 |
| Arduino TinkerKit Braccio | 6 servo motors (axes not stated) | 80 cm maximum operating distance | 150 g at 32 cm; 400 g at minimal configuration | $275.00, Arduino board not included | No printer needed; 21 plastic parts supplied |
Printing Versus Buying a Kit
Arctos says the main limits on the precision of a 3D-printed arm are generally not the stepper motors themselves. Precision depends more on the rigidity of the plastic parts, the materials, the payload, the speed and the control system, according to Arctos. If precision matters for your project, ask each maker which materials and payload its figures assume, because only Annin Robotics publishes a repeatability number.
The Arduino TinkerKit Braccio needs no printer, and Arduino describes it as a fully operational robotic arm controlled via Arduino. It costs $275.00 at the Arduino US store at the time of writing, and the Arduino board is not included. It has 21 plastic parts and six servo motors (two SR 311 and four SR 431), weighs 792 g fully assembled and has an 80 cm maximum operating distance. Arduino lists a maximum weight of 150 g at a 32 cm operating distance and 400 g at the minimal configuration.
Elephant Robotics describes its myCobot 280 as a "Best Robot Arm for DIY Projects" and says it includes a Raspberry Pi 4. This guide's sources hold no price or payload for the myCobot 280, so read both on the Elephant Robotics shop. Our guide to do-it-yourself (DIY) robot arm kits covers more options, and our robot arm price by brand page lists prices by maker.
Who Should Skip Printing
Skip printing the Arctos parts if you have no printer with at least a 200 x 200 mm build volume, the minimum Arctos states. The pre-manufactured 3D Printed Kit from Arctos supplies all the required plastic parts instead. For the AR4-MK5, C.I. Printing sells a printed covers and spacers set at $299.98 at the time of writing. Annin Robotics publishes no price for printing the AR4 parts yourself, so the listed figures give you no cost for that route.
Skip an arm if your payload exceeds the figure that arm lists (Arctos 2 kg, AR4-MK5 4.15 lb). Skip Arctos if you need a published accuracy figure before you buy. Buy the Braccio instead if you want a listed price of $275.00 before the Arduino board for an arm that needs no printing and can work within 150 g at 32 cm. Neither Arctos nor Annin Robotics states support terms in this guide's sources, so ask each maker about support before you order.
What the Makers Do Not Publish
Several figures a builder would want are missing from both maker pages at the time of writing, and they are listed below. At The Bot Scout, we have not built or ordered any arm on this page; every product fact comes from the maker pages listed in the sources. The precision, payload and price figures here are maker claims with no independent test behind them.
Ask Arctos for a repeatability figure at your intended payload before you choose it for any project that needs repeat positioning. Ask Annin Robotics what printing the AR4 parts yourself costs compared with the $299.98 covers set. If Arctos publishes a repeatability number, or an independent test of either arm appears, the choice between these two would rest on more than price and listed specs. Start by pricing the Arctos tier you need on the Arctos site.
- An Arctos repeatability or accuracy figure
- Total build time for Arctos
- Filament cost or print time for either arm
- A price for printing the AR4-MK5 parts yourself
- Any independent test or third-party review of either arm
Bottom Line
Pick Arctos if you own a printer with at least a 200 x 200 mm bed and want the lowest listed entry price, from $231 at the time of writing. Pick the Annin Robotics AR4-MK5 if you want a published 0.25 mm repeatability figure and can budget at least $1,888 with motors, before shipping and tax. Skip printing Arctos if you lack a printer with a 200 x 200 mm bed, and skip Arctos if you need a published accuracy figure. The $275.00 Arduino TinkerKit Braccio needs no printing and lists 150 g at 32 cm. A published Arctos repeatability figure or an independent test of either arm would change this pick.
See our DIY robot arm kits guide to compare more arms you can build yourself.
FAQs
How much does a 3D-printed robot arm cost?
Published kit prices start at $231 for Arctos at the time of writing. The Annin Robotics AR4-MK5 combo kit is from $1,189, or $1,888 with the $699 motor package, and $2,326.98 with the printed covers set and the gripper parts kit added. All figures are US dollars before shipping and tax. Neither maker publishes filament cost or print time.
Can you 3D print a robot arm at home?
Yes, both open-source arms on this page offer a print-it-yourself route. Arctos sells CAD files for self-printing, including STL files and pre-oriented 3MF files, and Annin Robotics says AR4-MK5 builders can machine the aluminum or print the parts. Arctos needs a printer with at least a 200 x 200 mm build volume. Arctos sells its motors and electronics in a separate Hardware Kit.
What size 3D printer do you need to print a robot arm?
Arctos states a minimum build volume of 200 x 200 mm for printing its arm. Annin Robotics publishes no printer size for the AR4-MK5 in this guide's sources. If your printer is smaller than 200 x 200 mm, Arctos sells a pre-manufactured 3D Printed Kit containing all the required plastic parts.
Is a 3D-printed robot arm accurate?
Only Annin Robotics publishes a figure, 0.25 mm repeatability for the AR4-MK5. Arctos publishes no repeatability or accuracy number. Arctos says precision in a 3D-printed arm depends more on the rigidity of the plastic parts, the materials, the payload, the speed and the control system than on the stepper motors. No independent test of either arm appears in these sources.
Are there open-source robot arms I can build?
Yes, Arctos and the Annin Robotics AR4-MK5 are both open-source six-axis arms you can build. Arctos describes its kit as an open source Arduino robot arm and publishes Grbl-based firmware on GitHub. Annin Robotics calls the AR4-MK5 an "open-source 6-axis arm for a desk" programmed in Python or ROS. Arctos kits start at $231 and the AR4-MK5 combo at $1,189 at the time of writing.