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Mechanical to Automatic???


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Hello watch lovers! 
 

Does anyone know if you can convert a hand wound mechanical watch into an automatic? I’ve looked a bit online to find an answer to my question but can’t seem to find any useful info. I’ve seen the video on converting quartz into auto but nothing on the topic I’m interested in. Do all you need to do is attach a rotor to make it automatic? 

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Many autos are actually based on manual calibers that have heavily modified bridges to accommodate the requirements of a bolt on auto module. If you look closely at some of the AS manual winders for instance you will notice that there are a lot of odd holes in the main plates and even in some of the bridges that don't seem to serve any purpose. Some of these are to make the main plate common to both calendar and non-calendar variants, and I would be surprised if some of them weren't for auto module functions. In fact if you look at Ranfft you will see in a number of database entries the whole movement family is listed, usually starting with the base manual movement, and progressing with the addition of complications.

I might therefore be possible to start with a manual winder that is part of a whole family of movements which includes autos and swap out all of the different parts to make it an auto, but the cost would be out of all proportion to simply buying the auto movement in the first place, and then it would be unlikely to fit in the case that the original manual winder came from, requiring a new case to be sourced as well. So theoretically possible, but why would you do that?

Converting a manual caliber that has no auto DNA included as standard is also feasible. Cimier has managed to add auto winding to the venerable Unitas/ETA 6497, a classic manual winder, have a look here. In fact a lot of the early autos were just that, but it's only possible if you have the design and manufacturing capability to devise and make the relevant parts.

Edited by Marc
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Much easier to go the other way. ;-)

But yeah, what Marc said. Check out the movement manufacturer's catalogues, and you'll see, for instance, a manual version of the typically automatic 2824-2. Specifically coming to mind is the Sellita version, as I recently came across a microbrand putting out a manual wind watch with a Sellita movement number similar to the SW200. It was just the manual wind version. If you wanted to, you could almost assuredly convert that to an automatic. You may need to track down some major components, and it might not fit in the original case, but the movement would be automatic. 

As for watches that don't fit into that schema... Anything is possible with enough time and money. Practicality is another conversation.

Generally speaking, it's not done.

Edited by spectre6000
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