Bigger Movements = Better Movements? (and Hello)

[Toby256]

Hello All,

After months of enjoying the forums here I thought it was finally time to join. My first post: I won't bore you all with too many details about myself - other than to say that my enthusiasm for watches has grown faster than my wallet - I own a Rolex Oyster Perpetual Submariner and an Omega Seamaster Planet Ocean - both secondhand but in perfect condition.

Anyway - to the point of my post which has been bothering me for some time:

Does anybody know if the size of a mechanical watch movement affects the precision, reserve power etc? If not, then why are multiple sizes available from the likes of ETA? Why not simply make one smaller ligne movement - and then fit it into an over-sized case?

Any ideas or thoughts appreciated.

Best regards,

Toby.

[lysanderxiii]

To a certain extent, yes. Very small (>8-3/4''') movements tend to have more positional variation than larger movements.

To a certain extent, no. Average size men's movements (10-1/2''' to 13-1/4''') can be held to the same accuracy.

[Toby256]

To a certain extent, yes. Very small (>8-3/4''') movements tend to have more positional variation than larger movements.

To a certain extent, no. Average size men's movements (10-1/2''' to 13-1/4''') can be held to the same accuracy.

Thanks lysanderxiii. Based on that, it sounds like the main drivers might be the practicality of fitting suitable hand sizes or locating any complications on the face...?

[lysanderxiii]

Mainly complications that require dial space.

[AbslomRob]

A larger movement tends to allow for a larger balance, which tends to be more accurate (all other things being equal). So in principle, to make a smaller movement as accurate as a larger movement, you have to manufacture it with tighter tolerances and put more effort into finishing it.

[lysanderxiii]

A larger movement tends to allow for a larger balance, which tends to be more accurate (all other things being equal). So in principle, to make a smaller movement as accurate as a larger movement, you have to manufacture it with tighter tolerances and put more effort into finishing it.

In practice, these days a 11.5''' or 13.25''' mechanical movement can be made as accurate as anything, even in high volume production.

The main reason big size 18 railroad grade pocket watches were made so accurate was because the were big and you could work on them easier. People that really know what they are doing can wring that kind of accuracy out of smaller watches these days.