az első teszt biztatónak tűnink (relatíve jól mozgatható az egérmutató)
újra szét kell szednem , az egyik potit fordítva kötöttem be, illetve meg kell néznem,
hogy a golyó pozíciójával lehet e valamennyit játszani ...

szóval javítási kísérlet

I"m interested in one of that  patkánys ...
I can ask in a near workshop as they  mould nitrilo toric  joints for autos.

I've mid-understood  SzörG in his web that his ball was solid gum with an oil treatment to make it more adherent...

I think the measures can be in inches, as rounded 12.7mm is 1/2", 6.35 is 1/4" and 32mm is 1+1/5".

It can be?

In the workshop they say the minimum order is of 100 units...

About the wheels they say each would cost 1.5 euro... but then you'll have to pay 150...

They don't do balls but can do hollow hemispheres (then you can fill with an iron ball and glue them). The price must be calculated.

The material can be silicone or other soft stuff.

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I don´t know... it's expensive. Better you try with that SzörG's balls. Filling them with sand or iron filings will do the trick.

But the wheels is the easiest part, they doesn't need to be soft, and there are gum joints utilized in old water taps that have that or similar measures. I will try to find some..

Here is one I`ve found in my tools-box. It has exactly 15mm outer diameter, 6 inner and 6 thick. Sadly only have one....

Sorry, it has been taken with the phone....

This is a water-seal, or auto parts?

In car repair shop can made a metal parts vulcanized rubber coating ...
still thinking about what it be a "base" of this ball? A ball bearings, or second-hang PC mouse ball?
My deodorant ball experiment is not good enough