Isochronism And Automatic Watch Movements

[WillFly]

I'm using the term "isochronism" here as the affect on watch regularity of the changing power released by an unwinding mainspring from "full" to "empty". It's a complex subject, of course, with all sorts of factors such as hairspring coil, mainspring material and shape, overall movement design, etc. having to be taken into consideration.

 

However, reading up about it, one comment caught my eye - the fact that an automatic watch is de facto always on "full". Does this mean that automatics are, by their very nature, better at dealing with the mainspring contribution to isochronism?

[autowind]

As you say,  an automatic should deliver a constant torque and therefore obtain a better rate,  then I thought that this would only apply if the watch was never taken off,  if taken off at night would it perform any better than a manual wind?

[WillFly]

As you say,  an automatic should deliver a constant torque and therefore obtain a better rate,  then I thought that this would only apply if the watch was never taken off,  if taken off at night would it perform any better than a manual wind?

Hadn't thought of that!

[Geo]

Does this mean that automatics are, by their very nature, better at dealing with the mainspring contribution to isochronism?

I think that it would be the case Will. If the power input is kept within a tight by constant winding, it surely must help the movement keep better time. :-)

[Geo]

if taken off at night would it perform any better than a manual wind?

On a percentage basis probably, provided it was worn everyday.

I use a watch winder to keep things on an even keel when I''m not wearing my autos.