A Tungsten slug ... hidden somewhere in the watch. Interesting concept. I imagine difficult to hide anything in a watch.
Agreed. Assuming we’re swapping out steel or brass parts that are easy to machine for tungsten versions of the same part. This watch weighs ~40g more than the SS version. The density of tungsten in 19.3g/cm3. And we’d be displacing steel (7.8g/cm3) or brass (8.7g/cm3) we have to swap out approximately 3.5 cm3 of steel or brass parts for tungsten parts to add 40g.
- an easy place to hide a tungsten slug might be the dial blank. Instead of brass for the blank, use tungsten. I don’t know exactly how big the day date dial is but let’s assume 30mm diameter and 1mm thick. That’s a volume of 0.7cm3… but that’ll only add 8g. That’s a start, but we’ll have to do better.
- the screw down caseback is 11.3g and is made of stainless steel. The same caseback made of tungsten would weigh 28g. That’s a gain of 16.7g… pretty good, but still a long way from 40g.
- There is a movement spacer / cradle ring between the movement and the case on this model; maybe that’s made of tungsten? This spacer ring could be ~3mm wide, ~7mm deep and around ~26mm in diameter (I’m guessing here). If we made that part out of tungsten it would weigh ~ 82g vs ~33g if it were made of steel. So that’s +50g.
I don’t have the exact dimensions of the movement cradle that holders the Asian ETA clobe movement that’s used in these GMF dayDates, but my guess is that the metal ring that secures the movement inside the case is the part that’s been swapped out for tungsten to add 40g to the watch. The movement ring is relatively easy to machine and doesn’t require precise finishing or geometry. And it means swapping one part in the assembly process to get a rep that’s a lot closer to the gen weight. But obviously not the gen weight distribution.