The crown is an essential part of a watch. It provides an important aesthetic element of a timepiece, but the crown is also the link between the heart of a watch and its wearer.

A crown is one of the critical points where water can enter a case. While the crystal and caseback are also danger zones, they are not meant to be opened by every person who owns a watch on a regular basis. 

 

Source: @finemods on IG

 

Given the danger, any watch made for underwater use needs to have a secure crown. On the other hand, watches that are made for the office will use a different system for the crown. Two common mechanisms that watchmakers use are screw-down and push-pull crowns.

You may be wondering which would suit you better and what makes the two systems different.

First of all, understand that both a screw-down and push-pull crown do not guarantee water resistance when set to the open position, meaning it is in the position where the time can be set.

Therefore, water can enter if you forget to screw-down or push in the crown.

Keep reading to understand what sets these two crown closing systems apart and which one is right for your Seiko mod.

 

What Are Screw-Down Crowns

Although the concept of the screw-down crown was not invented by Rolex, it was first used by Rolex in 1926 in the Oyster case. The founder of Rolex, Hans Wilsdorf, actually bought the idea from the two watchmakers Georges Peret and Paul Perregaux.

 

Source: A Blog to Watch

 

To this day, a screw-down crown is universally preferred in water-resistant watches. 

The principle of the screw-down crown is simple. There is a part of the case called the crown tube, which may or may not be removable, that has a screw thread. The inside of the crown is also threaded. The thread releases when you unscrew the crown and it opens the crown for use.

When it is in an unscrewed position, the screw thread will press against the tube and close any gaps from within using an O-ring seal.

 

 

Otherwise, in the screwed state, one of the rings will be pressed against the tube. In simple words, this type of crown screws tightly into the case to prevent water and dust from entering the watch.

With this system, the crown and tube assembly creates an airtight space, sealing any gaps around the watch that can let water and moisture enter the watch. This serves an essential function for diving watches as this allows divers to enjoy time underwater without worrying about their watches. 

 

 

Seiko also uses screw-down crowns for most of its timepieces such as its popular SKX watches, which are extremely cheap alternatives to the Rolex with a similar crown closing system.

Also, a screw-down is best for keeping dust from entering the timepiece. As you know, once dust enters the watch, it can settle on the components and make the lubricants between components dry up. 

 

What Are Push-Pull Crowns

The pull-push crown is standard in most casual watches. 

Unlike the screw-down crown, a push-pull crown doesn't need manual unscrewing to operate the movement. As its name suggests, you can pull the crown out and adjust the day, date, and time then you push it back in to seal it in its place.

 

 

With a mechanical watch with this push-pull crown, you can wind the watch in its place without pulling the crown out. Also, watchmakers use an O-ring seal with lubricants on a push-pull crown to reduce friction or wear and tear from frequently using the crown.

Pull-push crowns can seal a watch securely up to 200 meters and more, therefore, they are not less waterproof than a screw-down crown. Seiko introduced the 5 Sports line to replace the SKX and one big change was the switch from screw-down crowns to push-pull style.

 

Comparison

With a screw-down crown, you’ll need to unscrew it first to use a manual winding function, and time or date adjustments. 

A disadvantage of using a screw-down crown is that you can easily damage it by overdoing the screwing torque. You can break the screw thread within the watch, making the crown and the timepiece not viable for use until major repairs are done.

 

 

Meanwhile, a pull-push crown can last longer than a screw-down crown since the latter is subjected to wear and tear. As said, it can be used for manual winding even in a pushed-in position and can be used to adjust time and date with just one pull.

However, if you forget to push the crown back in, it can allow water or dust to enter and damage the movement.

 

Which One Is Right for You?

Choosing the crown will actually depend on which case you are using. Most modding cases which are modeled after the SKX007 will most likely have a threaded case tube suitable for a screw-down crown. 5KX cases, however, typically feature a push-pull crown.

Seiko mods allow you to watch mod parts, and create whatever kind of design you want. At namokiMODS, we have loads of options for you, so you can use OEM Seiko spare parts, or aftermarket Watch spare parts to make the mod of your dreams.

Learn more about all the parts we offer, including aftermarket screw-down crowns that work with the classic Seiko SKX007. 

Happy modding!