IWC 7750 chronograph

[Jon]

Hi Guys,

I was just setting the chronograph hand on this IWC 7750 and noticed how far out the minute counter sub-dial is from centre.

The chronograph hand is set pretty much exactly at 12 O'clock, but if you look at the track of the sub dial it is off to the left. Clearly the chronograph sweep second hand is central as it is also central to the rivet of the sub-dial hand.

Incidentally, I had to close up the pipe of the sweep second hand by 0.01 mm to have a tighter fit on the arbor and re-rivet the rivet on the top of the hand, so the hand wouldn't slip whilst returning to zero. I find a lot of these sweep second hands need work to get them to fit really tight and not drift, as this one was. The last pic shows the rivet that I re-rivetted. You can see how it is slightly flattened on the top to create a tight fit between the rivet and pipe, so the hand doesn't flap about on the pipe when returning to zero.