Properly sizing a watch mainspring to fit its barrel is an essential step in watchmaking. It ensures the movement’s efficiency, improves its accuracy, and prolongs its lifespan. However, knowing the right size mainspring for your watch can be daunting without proper guidance. That’s why we have put together a comprehensive guide on the essential steps to correctly size a watch mainspring to fit its barrel. In this article, we will explore the factors to consider when selecting a mainspring, tips to help you determine the correct size, and methods to ensure a perfect fit. Whether you are a professional watchmaker or an enthusiast, this guide will provide you with valuable insights to help you maintain your watch’s performance and extend its lifespan.

Essential Steps to Properly Size a Watch Mainspring to Fit its Barrel

Introduction

A mainspring is a crucial component of a watch movement that provides the power necessary to keep the watch running. Incorrectly sizing the mainspring can cause problems with amplitude and regulating the watch. In this article, we will discuss how to size an incorrect watch mainspring effectively. We will provide you with the essential steps required to fit the right mainspring into your watch barrel. So, let’s dive in!

Step 1. Calculation of Mainspring Strength

The video explains how to size an incorrect watch mainspring. The first step is to calculate the mainspring strength required for your watch. The formula to determine the strength, length, and width of the mainspring is based on the inside dimension of the barrel. You need to measure the inside diameter of the barrel to know the length and strength of the mainspring required.

Step 2. Sizing the Mainspring

Once you have calculated the required strength, you can determine the size of the mainspring to fit the barrel. It is essential to note that mainspring sizing in vintage watches does not have to follow exact factory sizing. There are different opinions and many different sizes of mainsprings available. Therefore, it is necessary to choose a mainspring that fits well within the range of appropriate sizes.

Step 3. Compensate for Wear in the Movement

Increasing the strength of the mainspring can compensate for wear in the movement, and it can increase available power. If a watch movement is worn, it can be challenging to maintain the correct regulation. In such a case, increasing the strength of the mainspring can be of help. However, the increase in strength should be minimal as an excess increase may cause long-term damage to the movement.

Step 4. Staying within Certain Parameters

The goal is to stay within certain parameters when fitting a mainspring into a watch movement. The measurements of your watch movement should be used to determine the strength, length, and width of the appropriate mainspring. It is also essential to note that you should use a high-quality mainspring. A low-quality mainspring may wear out even before you know it, leaving your watch movement powerless.  

 

 

WATCHMAKING TOOLS SEEN IN THIS VIDEO ARE AVAILABLE ON AMAZON!

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Bergeon Screwdriver Set

 

Dumont Tweezer #3

 

Bergeon Springbar Tool

 

Bergeon Case Opening Ball

 

Bergeon Presto Hand Removal Tool

 

Bergeon Movement Holder

 

Horotec Hand Setting Tools

 

Rodico

 

Bergeon Blower

 

Bergeon Case Opening Knife

 

Bergeon Quick Service Kit

 

Ultrasonic Cleaning Machine

 

Amscope Microscope

 

Multifunction Timegrapher

 

Sanding Sticks

 

 

CAMERAS AND AUDIO:

 

Main Camera, Sony A7III

 

Secondary Camera, Sony RX100

 

Tertiary Camera, Sony A6400

 

Main Macro Lens, Sigma 70mm f/2.8

 

Secondary Macro, Laowa 100mm f/2.8

 

Camlink 4k Video Converter

 

Shure MV7 Microphone

 

Audio Recorder, ZOOM H6

 

Small Sirui Tripod

 

Sirui Tripod Head for Overhead Camera

 

COMPUTER STUFF:

 

Apple Macbook Pro

 

Synology NAS

 

Seagate HDDs for NAS

 

Samsung Portable Drive

 

Conclusion

Correctly sizing a watch mainspring is crucial for your watch’s performance and lifespan. Following the essential steps discussed above will ensure that your watch runs smoothly and efficiently. Therefore, when fitting a mainspring into a watch, you should know what parameters to keep in mind and how to calculate the strength necessary to keep the watch running accurately. Always ensure to use a high-quality mainspring for maximum efficiency and longevity.

FAQs

1. What is a mainspring? A mainspring is a flat strip of spring steel that provides the power to keep a watch running and is coiled inside the barrel.
2. Why is it important to properly size a watch mainspring? Incorrectly sizing a watch mainspring can affect the amplitude of the watch and lead to issues with regulating the time accurately.
3. What happens if the mainspring is too strong? If the mainspring is too strong, it can cause long-term damage to the watch movement. It may also reduce the accuracy of the watch’s timekeeping.
4. Can mainspring sizing in vintage watches differ from exact factory sizing? Yes, mainspring sizing in vintage watches may differ from exact factory sizing. Therefore, it is essential to choose a mainspring that fits into the range of appropriate sizes.
5. Should I use a high-quality mainspring when fitting a watch? Yes, always ensure that you use a high-quality mainspring when fitting one into a watch. A low-quality one may wear out easily, leaving your watch with no power and may cause long-term damage to the movement.