Windup Bunny

Author: gzumwalt, published on 2016-03-04

Click this button to get the 3D model


I am yet again truly honored and humbled, this time by the Thingiverse feature of Windup Bunny. Many thanks yet again Thingiverse for the feature! And many thanks to all of you who made, liked, commented, critiqued and/or added to your collections, Windup Bunny!

My 100th Thingiverse published design is Windup Bunny, which is yet another incarnation of the PLA Spring Motor Demonstrator ( and the PLA Spring Motor, Rolling Chassis (, in simplistic “open frame” design. All parts, including the spring, are 3D printed with the exception of the O-ring “tires”.

Just in time for Easter, I made quite a few of these things for my wife (as she cannot eat chocolate, bunnies included) and of course for the kids and grandkids! Featuring all wheel drive to prevent “wheelies” and/or “back flips”, the prototypes of this thing run about 15 feet (4.572 meters) after lubrication and break in on a smooth surface.

Video of prototype is here: (no one was available to help with the video, so I shot it on the desktop, sorry).

If you do not prefer the “open frame” design (as in Saber, I like the open frame design as it demonstrates the gear movements, etc., and in this application it is lighter in weight which improves travel distance), I’ve included optional solid body side panels “Body Left, Solid.stl”, and “Body Right, Solid.stl”. Hopefully Loubie will create 3 dimensional side panels!

Print yours in the colors of your choice, and Happy Easter!

Designed using Sketchup Make 2015. Printed in PLA on an Ultimaker 2 Extended using Cura settings as described in Print Settings.

Print Settings

Printer Brand: Ultimaker

Printer: Ultimaker 2

Rafts: No

Supports: No

Resolution: .1mm

Infill: 20%, with exceptions, see notes.




Thingiverse member 510thousandths posted a 3D printable o-ring using flexible filament here: I have not yet tried it (as I do not have flexible filament), but I plan on doing so. Thanks 510thousandths for your input!


Parts I Purchased:

1) #18 O-Rings (1 3/16″ OD, 15/16″ ID, 1/8″ D) (Amazon, Lowe’s, Home Depot, etc., Danco 96735). The box I purchased contained 10 O-rings.


Print all pieces as shown in “Assembly.skp” or “Assembly.stl”.

Test fit and trim, file, sand, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on the colors you chose, your printer and your printer settings, more or less trimming, filing and/or sanding may be required. If the tight fitting components are too loose, add a small dot of thick cyanoacrylate to the side(s) of the male component, allow to dry completely (I use accelerator to speed the process), then try the fit again. Repeat until tight.

Assemble as per “Assembly.skp” (or “Assembly.stl”).

Apply light machine oil to all moving contacting surfaces.

Questions, problems, complaints, etc., please feel free to comment and I will do my best to resolve them.

Hope you enjoy it, and Happy Easter!

License: Creative Commons – Attribution – Non-Commercial

Tags: Bunny, Easter, Easter Bunny, PLA Spring Motor, Spring Motor, Windup