Hi all! I am confident that we’ve all had moments of nostalgia, whether that be seeing an old friend or watching a show that you liked when you were young. A big thing in my past was fidget spinners. I was around 7-8 years old when it was released and I immediately bought 5 from Amazon and the local 7/11. This was the era in my life where Pokemon cards and Lego were big pastimes. A fidget spinner looked easy to make, so why don’t I just make one for my CAD project?
Main Frame
The main frame of a fidget spinner is essentially 4 rings, one in the center that holds the bearing (the object that allows the spinner to spin), and three for the weights. I modeled and sketched the frame to utilize a bearing that I have on hand of 0.865 inches.
The frame is currently only a sketch. To make it an actual object, I extruded the sketch’s rings to 0.275 inches thick. Again, the values are to fit my bearing.
The extrusion feels a bit unrefined. Although the general shape is right, it does not look like a fidget spinner. To fix that, I filleted the edge of the rings to 0.1 inch to give the outside ring a bit more curve. Additionally, I filleted the point of contact the three outside rings have with the middle to give some more flow to the design.
Caps
The two caps are the places that the person holds on to. There are two parts of a cap: the grips and the connector. The former will remain the same, however, the connector parts will be different. This is because the second cap will need to fit inside the first cap, or else the caps simply won’t work.
Connectors
The first connector will be the one touching the bearing and will be a ring so that the second cap’s connector can go inside. The outside circle will be 0.345 inches and the inner will be 0.245 inches.
The second connector will fit inside the first one. It will have a diameter of 0.24 inches.
I then extruded both of them to 0.285 inches.
Grips
The grips for both caps are going to be the same. I sketched the circle, which is 1 inch.
I then extruded both of them to 0.1 inches.
Since they both looked extremely janky, I filleted the edges by 0.1 inches.
Bearing
The bearing is what allows the fidget spinner to spin, as the inside ring is fixed while the outside is able to rotate. I first sketched it out using the values I collected from mine. Then, I extruded both rings to 0.275 inches, the same size as the main frame, and the middle area to 0.27 inches.
Weights
The weights are an essential piece to the fidget spinner. It creates the inertia/power required to keep the spinner for a long time. The weights have a very simple design — a ring. I sketched it out. Then, I extruded my sketch to 0.275 inches, the same as the main frame, and filleted the inner ring to 0.1 inches.
Assembly
I first fastened the the weights onto the frame, as they should not be able to come apart.
Next, I revolve-mated the bearing to the main frame, the first cap to the bearing, and the second cap to the first.
Some of you readers may not have a 3D printer or bearing at home. Fortunately, Onshape has an Animation function to visualize your fidget spinner. To use this function, I utilized a gear relation on the first two revolve-mates. Now, just right-click one of the first two revolve-mates, press play, and you should be able to see your fidget spinner spinning!
Bill of Materials (BOM):
Mechanical Drawing of Assembly
That’s it! Thanks for reading this blog post!
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