Introduction
Hello, this is Classical.
When reading posts about watch overhauls, I often come across two conflicting opinions:
- “Lubricants never Dry Out.”
- “Lubricants do Dry Out.”
These statements seem to stem from a misunderstanding of the term “Dry Out.” To clarify this, let’s dive into the details.
What Are Lubricants?
Lubricants are oils applied between mechanical components to reduce friction. According to NamuWiki:
“Lubricants, in a broad sense, are oils applied to reduce friction between mechanical parts. Their origins vary, ranging from whale oil in the past to petroleum-based oils that dominate today. Since the 20th century, petroleum-based lubricants have become the standard.”
(Source: NamuWiki)
The primary role of lubricants is to create a thin film between components, minimizing wear and heat caused by friction.
Types of Lubricants
Lubricants are categorized into three main types:
- Fatty Oils
- Derived from animal or plant sources, such as whale or olive oil.
- Rarely used in modern times due to limited stability and availability.
- Mineral Oils
- Refined from crude oil but contain trace impurities like sulfur.
- Widely used because they are affordable and effective.
- However, they degrade faster at high temperatures and may require frequent replacement.
- Synthetic Oils
- Chemically engineered to address the limitations of mineral oils.
- Provide superior stability and longer usage intervals.
- Costlier but more effective in protecting machinery.
Modern lubricants often include additives to enhance oxidation resistance, reduce friction, and improve performance.
Why Lubricants “Harden”
Lubricants undergo thermal and oxidative degradation over time. This process results in:
- A drop in viscosity.
- The formation of byproducts like oxidation residues and metallic particles.
These changes eventually cause the lubricant to harden, a phenomenon commonly mistaken for “drying out.” In reality, it’s a chemical transformation, not evaporation.
Key Point: Instead of saying “the lubricant has dried out,” the correct terms are “its viscosity has decreased” or “it has hardened.” These expressions better reflect the chemical processes involved.
Lifespan of Watch Lubricants
The shelf life of lubricants used in watch movements is typically between 3 to 6 years. For example, Moebius Synt-A-Lube 9010, a popular watch oil, has a shelf life of 6 years when stored properly. Once opened, exposure to air accelerates oxidation.
This is why manufacturers recommend periodic overhauls every 3 to 5 years. Overhaul intervals align with the expected lifespan of the lubricant in use.
Modern Advancements
Recent innovations in lubricant technology have delayed the hardening process. However, even the most advanced lubricants are not immune to degradation. Ignoring maintenance can lead to uneven wear and potentially expensive repairs.
Summary
To summarize, all lubricants will eventually harden due to natural chemical processes. Using precise terminology like “viscosity breakdown” or “hardening” provides a clearer understanding than simply saying “it has dried out.”
Regular maintenance is essential to preserve the functionality and longevity of your watch.
In short: there’s no such thing as a lubricant that doesn’t harden. If someone discovers one, they might just win a Nobel Prize!
