New vs. old FOIS dial question…

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Would any of you fine folks know: can the new FOIS cal. 3861 dial be retrofitted to the old 1861 FOIS? Thanks.
 
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I've seen a successful mod of a FOIS2 dial in a professional from @Ron_W, not sure if that would apply to the FOIS1 case as well;

 
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Would any of you fine folks know: can the new FOIS cal. 3861 dial be retrofitted to the old 1861 FOIS? Thanks.
Yes, they share the same dial feet.
 
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I ask because this is what I found on the net:

No, dials from Omega's calibers 3861 and 1861 do not share the same dial feet, making them non-interchangeable. This is because while the 3861 is an evolution of the 1861, Omega states that more than half of the parts are not interchangeable between the two movements.
Although both movements are similar in overall architecture and beat at the same frequency, the 3861 contains significant upgrades that affect component placement. These include:
A different jewel count (26 in the 3861 versus 18 in the 1861).
The inclusion of a Co-Axial escapement and a silicon hairspring for anti-magnetism.
The addition of hacking seconds.
These internal differences affect the design and layout of the movement's components, including the location of the pin holes for the dial feet. A dial from an 1861 movement will not correctly align or fit onto a 3861 movement, and vice versa
 
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I ask because this is what I found on the net:

No, dials from Omega's calibers 3861 and 1861 do not share the same dial feet, making them non-interchangeable. This is because while the 3861 is an evolution of the 1861, Omega states that more than half of the parts are not interchangeable between the two movements.
Although both movements are similar in overall architecture and beat at the same frequency, the 3861 contains significant upgrades that affect component placement. These include:
A different jewel count (26 in the 3861 versus 18 in the 1861).
The inclusion of a Co-Axial escapement and a silicon hairspring for anti-magnetism.
The addition of hacking seconds.
These internal differences affect the design and layout of the movement's components, including the location of the pin holes for the dial feet. A dial from an 1861 movement will not correctly align or fit onto a 3861 movement, and vice versa
Someone's AI is lying to you: https://omegaforums.net/threads/is-moon-watch-chronometer-3861-and-1861-dial-right.136607/
 
Posts
1,633
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5,162
I ask because this is what I found on the net:

No, dials from Omega's calibers 3861 and 1861 do not share the same dial feet, making them non-interchangeable. This is because while the 3861 is an evolution of the 1861, Omega states that more than half of the parts are not interchangeable between the two movements.
Although both movements are similar in overall architecture and beat at the same frequency, the 3861 contains significant upgrades that affect component placement. These include:
A different jewel count (26 in the 3861 versus 18 in the 1861).
The inclusion of a Co-Axial escapement and a silicon hairspring for anti-magnetism.
The addition of hacking seconds.
These internal differences affect the design and layout of the movement's components, including the location of the pin holes for the dial feet. A dial from an 1861 movement will not correctly align or fit onto a 3861 movement, and vice versa
Well this text doesnt make much sence to me. Feels like an AI generated text.

I only tried it once to fit the gen2 FOIS dial on a gen1 FOIS. i had no problems. Back then i couldnt find any information online so took a risk teying it out myself.
I havent measured the exact dial diameter or concave shape of the dial. So i dont know if there are any limitations in this respect.

Here what my watch looked like:

next to other dials for comparison: