3D Printed Modular Ball-and-Socket Joints




Introduction: 3D Printed Modular Ball-and-Socket Joints

About: I'm a Mechanical Engineer who has been a part of this community for over 10 years! My interests have evolved over time, and now center around 3D printing.

During my stay as an Artist in Residence at Instructables I was able to witness firsthand how awesome 3D printing can be.  I was surprised how exciting it was, because I had never used any 3D design programs or seen a 3D printer in action.  There's a certain thrill about pulling your creation out of the printer for cleaning and seeing it exactly as you had designed it on the computer.  One thing I found especially exciting about 3D printing is the ability to print movable parts and joints without any assembly required after they are printed.

Therefore, it was a goal of mine to 3D print something before I left the Pier.   I didn't end up doing this project until my last day because I was occupied with my main project, but that didn't make it any less exciting.

This Instructable will show how I 3D printed a modular series of ball and socket joints.  It has no practical use in its present form, but it is fun to play with!  The concept itself could be applied to a range of awesome projects in the future.

Link to the *.123dx model: https://www.dropbox.com/s/qwp8jvsp9kni7sr/ball%20and%20socket.123dx
Link to the *.stl model: https://www.dropbox.com/s/8i03tu7jw7yay8z/ball%20and%20socket.stl

Step 1: Video!

Step 2: Design

I created my model of the ball-and-socket system in 123D Design.  I originally played around with Tinkercad, which I'm actually more fond of, but 123D Design offers a lot more functionality (if only it would stop crashing on my computer).

The model is composed of all simple shapes.  I began with a sphere.

A toroid was generated to have roughly the same inner diameter as the sphere's outside diameter.  I left a little bit of space so that the parts could move freely.

Two smaller toroids were generated, and their diameters tweaked so that they could "cup" around the two sides of the sphere (Pic 5-7).  These were set into position with a small gap in between them and the sphere.

It was at this point in the process that I realized be allowing the largest toroid to be a complete circle, I was limiting the motion of the joint without adding any meaningful stability to it.  I made a large box to "cut" part of the largest toroid, and then combined the three toroids together as one solid(Pic 8-10).

The toroid structure was rotated sideways, and a cylinder was generated and placed on the face of the largest toroid.  The end of the cylinder was "Chamfer"-ed to make the joint a little more smooth-looking, and combined with the toroid structure (Pic 11).

At this point an identical sphere was generated and combined with the cylinder-toroid structure.  This is our completed piece, and the original sphere can be deleted.

The piece can now be copied and pasted.  Each piece should be aligned with the sphere inside the toroid structure.  When it is printed, the parts will be able to move freely but not be separated.

Step 3: Printing!

The file should be exported as an .stl.  This will be used in the Objet suite to actually print the part.  I've attached the .stl I made in this step.

Mine was printed in the "VeraWhite" material, since it was the easiest at the time to get my hands on, and this part has no functional purpose that would demand something different.

I wish I had taken some pictures of the part being cleaned, but it was nothing too strenuous or complicated, and my hands were busy.

If you're wondering about using an Objet 3D printer, or the cleaning process, the best place to look is M.C. Langer's Instructable: https://www.instructables.com/id/Beginners-Guide-to-3D-Printing-with-the-Objet-Con/

Step 4: Conclusion

I realize this is a quick Instructable, but we should still have a conclusion!

Now you have your very own 3D Printed Ball and Socket Joint(s) to play around with!  The design and concepts could be used for something useful.  Something I had in mind was a pose-able helping-hands sort of thing, but the posibilites are endless!

You should leave me a comment!  I like those! They help keep me motivated to publish articles instead of letting the pictures I took rot on my hard drive! : )



  • Water Contest

    Water Contest
  • Fix It! Contest

    Fix It! Contest
  • Tiny Home Contest

    Tiny Home Contest

10 Discussions

I uploaded them along with the pictures, so it should be an attached file. I couldn't find them myself when looking at the Instructable, so I'll look for a different method of uploading them.. Thanks for pointing that out!

Any luck uploading that .stl file? I still can't find it on the instructable. Thanks.

I added some links to the intro. Thanks for the reminder I hope those work for you.

With a little modification, this would be a great addition to the art doll accessories. You could use these as armatures to build your art doll around and have good flexibility for posing etc

1 reply

That's a very good point! These could easily form a sort of skeleton. However, it would need to be modeled with closer tolerances to allow for pose-ability..

Really neat model! I used the 123D Design iPad app to make a model yesterday. It is so simple yet so powerful! That is what I really like about the 123D CAD software.

3 replies

Thank you! 123D Design is pretty awesome. I had never touched a 3D design program before but was able to pick it up quickly!

That's great! Those who are part of the instructables community are always quick to pick things up! Are you going to continue 3D modeling and printing?

One thing I learned about 3D printing is that even though it's awesome, it can take a few prints to get things perfect. Without having access to a 3D printer now, I'd have to buy my prints through Shapeways or elsewhere, and then they might not be perfect when I get them.. So no, sadly.

I may use those services for specific parts that I can't make any other way, but money is always a constraint when I'm making projects at home.. 3D printing isn't cheap, and neither is college hahh..