Intro: Hex Nut Spinner
It seems like spinners and fidget toys are the latest fad. Although late to the game, I thought I would take a try at making my own.
I was at a trade show recently and the 3D printer company Lulzbot was giving away spinners at their booth. I was pretty disappointed with the design since I couldn't get the spinner to make more than two revolutions on a spin. To their credit, it was FREE and the main purpose for the trinket was to market the printer. Anyway, I pulled it apart and recycled the bearing and caps. My larger version was printed and uses the bearing and caps from the Lulzbot. The cool part is the six 1/2" hex nuts that were added for weight. As you can see in the video, it spins nicely.
Step 1: Parts
Step 2: Dissection
This is the original spinner. The bearing part number is 608-2RS (22mm OD, 8mm Shaft). You can purchase this bearing from Ebay, Amazon, McMaster-Carr, etc. I used the end caps for my build but this link provides a downloadable version in case you would like to print your own.
Step 3: Spinner 3D Print
The design was kinda arbitrary. After deciding to use the 22 mm bearing, I found six 1/2" hex nuts in my junk drawer so I worked around those dimensions. The overall diameter (3.88") is on the large size for spinners. If you are building this for your kid, you might want to do some finger measurements first.
All joints are press/interference fit (no glue). The part printed slightly smaller than the CAD file so I had to spend about 5 minutes using a file to make everything fit.
I've included the STL file in this step. I've also included a STP file in case you would like to make modifications to the design.
Step 4: Assembly
I'm not showing the assembly steps since it is obvious. Insert the bearing into the center hole. Being lazy, I assumed the hex nut thickness would be the same as my downloaded STP file. My hex nuts were actually a little thinner. Therefore, I needed to center them in the 3D print which wasn't a big deal. Note that using a vice or arbor press and a matching diameter socket makes pressing in the parts easier. The end caps snap on to the shaft diameter. That's it!
Step 5: More Pictures
Step 6: Size Comparison
There is a significant weight difference as well.