Custom building this Arm
is possible to build this arm by just buying CAD FILES doing cnc machining and steppers from online and another parts sourcing locally , has anyone done like this.
thanks for your response
.Once after acquired the AR4 MK3 CAD Models (SolidWorks & STEP files) and I would like to proceed with CNC machining the aluminum parts.
Before starting, I wanted to confirm a few points:
- Are the provided CAD files fully suitable for CNC machining without additional modifications?
- Are there any specific parameters, tolerances, or machining requirements that I should provide to the CNC operator to ensure the parts assemble correctly?
- Do you have any recommendations or tips to maintain the precision and integrity of the robotic arm components during machining?
I appreciate any guidance or documentation you can share to ensure a smooth manufacturing process.
Thank you for your time and assistance.
Hi Santhosh,
I have done this twice already, here are the forum posts documenting my 2 builds.
First build: AR3 later converted to AR4: https://anninrobotics.com/community/robot-builds/ar3-in-florida
Second build, this summer with my nephew and his friend:
https://anninrobotics.com/community/robot-builds/ar4-round-2-a-summer-project
The machining from the CAD model is pretty straightforward and can be done with a 3 axis and a lathe. Please note that some parts need to be 3D printed (enclosure, covers)
Feel free to reach out if you have questions.
7 replies

Chris Annin
Hello, yes many people have built the arm this way.
Santhoshkumar Kumar
thanks for your response
Hi, I’m looking to understand the complete part list of the AR4 MK3 robot arm.
Thanks in advance!