1570 Movt.

[rusi]

hi,
The 1570 movts. came with non-hacking & hacking movts.
Whats the difference between these machinerys.
The change in these movts. came in 1972 i think, but whats the actual difference, & can non hacking be changed into a hacking one?
Seniors guidance please.

[Lol-x]

The non-hacking movement cannot be changed to a hacking movement. There is an additional component in the hacking model and I believe there is also an additional machined section on I think the movement main plate to facilitate the seconds being stopped when the crown is pulled out.
However, I'm not technically qualified, so correct me if I'm wrong.

[Ironstark]

Sorry, not use to the term "hacking" but from Lol-x`s post I guess you mean the stop seconds function.
The actual physical difference between them is as follows.
The stop seconds version (hacking) has a portion of the baseplate milled out to allow the inclusion of a lever/spring which works with a pin on the setting lever. When the stem is pulled out this lever moves foreward and blocks the balance wheel. The non hacking version does not have the milled portion or lever. It is not possible to convert the non hacking into the hacking version. (unless you had all the right tools and equipment and all of the necessary parts and expertise, I suppose it is technically possible but I have never heard of it being done and it would be far more trouble than it was worth)
It would be easier to change the baseplate for the newer version and get the stop lever.

[Lol-x]

Thanks Ironstark for the technical information.
I have a non-hacking GMT, that I wish was hacking, but I know this is not practically possible to change, so I guess I have to accept what I've got as there is no easy way to change non-hacking to hacking and I'm sure Rolex will not perform that as part of a service upgrade.