Jewelery magnetic polisher - Handmade by CMS

Fixed electromagnets will not have this effect. However, it should also work to some extent.
Note that at the maximum RPM - 3400rpm, the magnetic field changes 13,600 times per minute, at the moment the inverter is set to 42Hz which gives 2400rpm which is almost 10,000 anyway.
I'm afraid the electromagnets could get hot. After all, each switching on and off causes a "current-voltage" surge, but I may be wrong.

This solution would significantly reduce the size of the machine.

CMS wrote:

After all, each switching on and off causes a "current-voltage" surge, but I may be wrong.

Eddy currents in the cores ... will do their job Here, a rotating magnetic field is generated mechanically, and this has great advantages (e.g. simple speed control of the drive motor). Marcin and ask the recipient how would fine steel shot work instead of needles. It seems to me that the frictional resistance on the bolt would be lower than on the pins.

The shot will not penetrate the processed material, which by definition has many small details. Needles squeeze into the smallest nooks and crannies.

CMS wrote:

Needles squeeze into the smallest nooks and crannies.

Apparently so, but pellets of 0.2 mm? It's almost like sand, and sometimes I give small details for sandblasting. If the shot worked, maybe he would build such a machine (I do not make rings ).

I think that if pellets were better than needles, jewelers would use pellets .
You see, the pellet only hits, and the needle hits the tip and at the same time rotates in some plane and as if it will make a scratch on a polished element. So we have not only stroke but also friction. The shot, on the other hand, "only" hits. The sand works well because it has sharp edges, except that it is much finer than the mentioned 0.2mm.

very nice machine, i have been looking for something like this for a long time to clean, can you tell what thickness did you use magnets? I can see that the plate is 20cm, what magnets to use with a diameter of at least 50cm or more?

Neodymium magnets 30mm diameter 5mm thick.