Infosheet-Fidget-Spinner

If a new ball bearing is needed for the fidget spinner, because the old one is defective or the fidget spinner should spin faster, then first of all it has to be identified which bearing is the right one. Usually the ball bearing on the cover (seal) is provided with a type designation. This is useful for determining which bearing is needed. If the bearing is open the type designations are missing and it has to be measured.

For your fidget spinner you can use bearings made of steel (100Cr6) with a nylon cage (TN)

If your fidget spinner is supposed to run faster, longer and more smoothly, hybrid ball bearings are the perfect choice. In this case the outer ring consists of stainless steel (AiSI 440), the cage is made of plastic (TN) and the bearing balls are made of the material ceramics (Si3N4). Another advantage of this material composition is that the ball bearings can be easily cleaned with water without corroding afterwards.

To achieve the lowest possible frictional resistance, all fidget spinner bearings run dry, so they are not greased.

The bearings are available in three different sealing variants:

open - ball bearing without seal
2RS - rubber seals on both sides
ZZ - steel seals on both sides

The seal serves protection from soiling of the runway. If there is some dirt on the runway, the bearing balls cannot run smoothly and fast. The seals can be removed if necessary.

Open bearings can quickly become dirty, but allow slightly higher speeds than bearings with rubber seals on both sides (2RS). Rubber seals create a low resistance through the contact surface between the bearing rings, which limits the freewheel of the bearing somewhat - for this they are very well sealed and therefore not susceptible to contamination. Steel seals (ZZ) on both sides seal the bearing completely down to a small gap, there are no losses with respect to the freewheel, as with open bearings.