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Regarding the Bergeon 5482 pivot rounding tool, does anyone have one and can you recommend it for the purpose of rounding and polishing pivots?

I’ve never bought a Jacot tool and thought this might work well for simple polishing, without having to mount the balance in my lathe (or a Jacot). 

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On 11/29/2020 at 5:43 PM, rodabod said:

Regarding the Bergeon 5482 pivot rounding tool, does anyone have one and can you recommend it for the purpose of rounding and polishing pivots?

I’ve got a hold of a Bergeon 5482 and it appears that the jewel is actually a burnisher as it has a rough surface. So, I would suggest not adding any abrasives when using it for three reasons - it’s should work just with light oil alone, abrasives could smooth the rough finish of the jewel, and since the polishing surface is harder than the pivot, any abrasive could be embedded into the pivot. 

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I forgot to add the photos of the jewel itself. I reckon it’s possibly just a very small (and expensive!) sapphire burnisher. That said, I tried it and it appears to work. My only question surrounding it is the suitability of the radius it creates for different widths of pivot, but we shall see.

Two photos attached - one is straight into the centre of the jewel, and the other is looking off-centre at an angle to capture the surface.  
 

 

60E31789-9C33-4717-A776-19932642B1C2.jpeg

CC95C7DB-06CA-4AD2-B276-D71FC4A4BCFB.jpeg

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