Do you have kids? If so, you probably got forced to buy one of the most stupid inventions of the last decade or so: A fidget spinner… Never heard of it? Lucky you… It’s time to change that! The most basic version of a spinner consists of four bearings held together in a triangular shape. You hold the center bearing and give the base a spin and watch it while spinning and spinning and …. Ah, and the best thing is that it comes in all kinds of shapes (and price classes), you can always buy more and new models to fill your junkroom. You might be asking what this is good for?! Well… Once you find out let me know — I have no idea…
My kids were determined to have one of those as well. So I showed them how to build one on their own. This way they will at least learn something in the process of making it.
It’s actually quite easy: Use a 3D printer to print this, buy one “good” and fast(!) ceramic ball bearing like this one and three ultra low quality ones like these as weights. You really want to have a fast ceramic bearing without lube in the center, otherwise the other kids are way cooler because their spinner spins longer — you really do not want to risk that…
So print it, clean it, and assemble it. The before mentioned ceramic bearing is good for spin times of way more than 60 seconds!
Ok enough with kids’ stuff. Back to the topic. I recently stumbled upon this video. A spinner made of giant ball bearings stuffed into each other — I have to admit that I immediately felt the urge to have such a useless toy as well! I changed the smaller ones to different bearings and used two bearings for the smaller ones.
In case you like tutorial videos and want to see it in action, here you go:
After watching this you probably want to build one as well. Lucky you, I prepared a shopping list for you!
The hardest part on building those is to buy the necessary bearings. You will need the following:
- 2x 606 ZZ (6 x 17 x 6 mm) [ebay.de 2€] [ebay.com $1] [ceramic on banggood $2]
- 2x 6903 ZZ (17 x 30 x 7mm) [ebay.de 2€] [ebay.com $2]
- 6006 ZZ (30 x 55 x 13mm) [ebay.de 2€] [ebay.com $3]
- 6011 ZZ (55 x 90 x 18mm) [ebay.de 8€] [ebay.com $7]
- optional: 6018 ZZ (90 x 140 x 24) [ebay.de 17€] [ebay.com $30]
A complete set comes at ~18€ or $16 plus shipping! Quite cheap when compared to other fidget spinners you can buy. If available buy the bearings without any cover or with the metal cover (ZZ or 2Z), those are easier to open up. If you can wait for the ceramic bearings to arrive from china — go for it, it makes the spinner run much longer! The biggest 6018 bearing is ridiculous large, there is really no need to buy that one. There is probably no one on earth that can hold and spin it without grinding his palm…
Once you got all the parts together it is time to open up the bearings and clean them. As we put no significant load on them we are going to remove all the grease. This way they are able to spin way faster and longer. Start by removing both metal shields by lifting it using a needle, knife, or a screwdriver:
Now put some solvent into a glass or metal jar and let the bearings soak. I used a gasoline based cleaning solvent similar to lighter fuel. Anything will do, just make sure to have a good ventilation and take the usual precautions in order not to set the house on fire…
Use a brush to remove the grease while the bearings soak. Once the grease is washed out you can use some compressed air to blow out the remaining slobber. You might want to do a second rinse in fresh cleaning solvent. Make sure to dispose the old solvent safely.
Now it’s time for assembly. The bearings should snugly fit into each other. I started with the biggest one and worked my way down to the smallest one:
If necessary add some very small amounts of superglue to keep the bearings in place. When done, add some very small drops of thin oil to the bearings in order to prevent rust.
In case you decided to go all in you probably ended up with this: A ridiculous large and 1588g heavy spinner no one can spin in their hands…
That’s all. Happy spinning!