Independents

Could you talk about how many of them there were, when they were made, and give us some historical tidbits about it. In a recent documentary, Dufour said he used a watch as an inspiration, can you comment on that watch? Also, please excuse my ignorance, b... 

Hi, Jay, Ph. Dufour completed 9 Dualities, in various metals and dial combinations. It is a complex escapement, considered by many to be even more complex than a tourbillon. Using planetary gears between the two escapements, the idea was to average out be... 

Here is a version now on display in a School watch exhibit in Geneva. The other I am aware of was sold through Antiquorum. I can scan in the picture if people are interested TCP...  

Nt

Both of these were in the Time Museum "F.P.V.J. Double Regulateur" Pocket Watch sold for $125,000 USD in 2004 Marine Chronometer by Hezekiah Conant Very Rare stuff and very interesting steps in the pursuit of accuracy. This is why I love the Dufour Dualit...  

line we have this amazing piece in 1931. Dufours in What year? and The other one was what year? I am correct then that there are only three examples in history of this engineering phenomena?

I recently discovered that Riefler (of uber-precision clock fame) also designed, and perhaps patented, a watch escapement that delivers impulse by the same principle as his clocks. The escapement displaces the outer point of attachement of the balance spr... 

I have heard of watches impulsed through the hairspring instead of the balance and was of the understanding the concept was not successful as it applied more disturbances to the balance spring worsening the rate. I do not recall more specifics or any info... 

There is a patent by Riefler for this escapement. I once had a copy and will see if I can find it and post it. I have given it a good look, but think it would only work for a clock. While we always say that increasing the free motion of the balance increa... 

Thanks Don. Does anyone have any experience of the FHF 72? It was apparently the only production freesprung movement for many years. The index pins are replaced by rollers which actually change the effective length of the balance spring. Did it work, did ... 

Hi Nick, I worked on a watch with this regulating system some time ago and it was not fun. I believe it was a Mido that I worked on and I recall the regulating system being called Incastar. It was odd enough to me that I took a couple of pictures: From Wa...  

I can imagine that with a decent beat control mechanism and meantime screws it could have potential. nick