Whenever I have the genius idea of swapping a metal bracelet for a leather strap on my favorite watch, I’ve got to deal with spring bars. Most of the time, I find spring bars annoying to use. With the smallest mistake, they spring out and fall on the floor and, by some magic, always seem to disappear. Or they slide off the bracelet end links when I try to align the latter with the lugs, or I can’t seem to make them fit through the tiny holes at the end of a strap. Although I always struggle using spring bars—and sometimes question their practicality and reliability—I never wondered how on earth we ended up with them. What’s the reason for their existence? Can we do away with them? These are some of the questions we’re going to address in this article
What Is a Spring Bar?
In a nutshell, a spring bar is made of a metal tube and two pins held together inside the tube by a spring. The pins are made to fit inside the lug holes of the watch and stay in place to hold a strap or bracelet securely. Most of the time, the tips of the spring bars come with indents to make it easier to grab them with a spring bar removing tool. Their design, as we will below, has not changed over the past century.
Wearing a Watch Before Spring Bars
If you want a detailed explanation on the history of spring bars, I recommend reading this excellent article on Hodinkee. Jack Forster has a unique way to make a boring subject interesting and he managed to get me hooked reading about spring bars. In a nutshell, there existed a transitional period between pocket watches and the first wristwatches. Pocket watches were attached to our clothes by way of a chain. Simple. However, when the first wristwatches appeared, how were they attached to the wrist? In the earliest examples, it seems that a watch head was an integral part of a decorative bracelet, meaning it was a piece of jewelry. The apparatus was strapped on the wrist thanks to the metal bracelet making up the jewelry. There was no way—and no concept of—of swapping a bracelet for a strap.
When Cartier created the Tank in 1917, it was indeed provided on a strap, however the strap would have been fixed on the watch case or screwed in. According to Jack Forster, wristwatches at that time would have come with one of two ways of installing a strap or bracelet: either they would be attached by way of a metal bar soldered to the case, or by a rod that was screwed in. In the latter example, changing straps was possible but not easy. So there was a need for an easier solution to swap straps and it seems there were several parents made starting in the 1920s for what we now consider as being a spring bar. Furthermore, modern military strategies of World War I required the usage of timekeeping devices and many attribute the proliferation of wristwatches to the war, therefore watch brands had to find better ways to customize watches.
And, perhaps, making spring bars more common.
The First Patents for Spring Bars
According to Forster’s detailed research, the first patent for a spring bar was filed in 1929 by one Isidor Dinstmann, a businessman whose family was in the jewelry and watch business. Dinstmann’s patent clearly shows the now classic construction of the spring bar and how easy it made changing straps. Before his patent, it seems that watchmakers would find different ways to attach a strap to a watch, as mentioned earlier, and in some cases to create watches that could be converted from being a pocket watch to a wristwatch. 1929 was just a decade before the beginning of World War I during which officers would have watches as part of their equipment. Knowing what we know about the first cotton straps and Marine National straps that soldiers used during World War II, we can assume that spring bars had become commonplace by the late 1930s.
The second patent I would like to mention is the one filed by one Robert Konikoff in 1946 (first filed, it seems, in 1944.) It shows again the typical spring bar construction and, according to Jack Forster, notes were included with the patent indicating that it was an improvement of a previous version. Given, again, that WWII soldiers would wear watches on straps, it seems that spring bars had been used for a while. Interestingly, however, it seems that the design of spring bars has not really evolved in the past few decades with a few exceptions. Most spring bars we see nowadays look rather cheap and flimsy, and the same ones are used on a $50 watch as well as a $5,000.
It's fascinating to realize that what we now take for granted didn’t exist a century ago. What seems like a simple invention required several patents and extensive research to get the right system in place. From what I understand, the need to create spring bars stemmed from the popularization of wristwatches and consequently the need to be able to easily change straps. Although some brands offer more luxurious and better made spring bars, most of the time they are items one can purchase in bulk for less than a dollar each.