You would be correct if we were dealing with high loads, temps, abnormal speeds, etc. This is the simplest application of an oil known to man. Thats why 1900 watches lubricated with nothing more than a 150 cst oil could be consistent to 3 parts in 86000
In the early 1900s, watch oils were primarily natural, non-synthetic lubricants derived from animal and vegetable sources. Here's a breakdown of their composition and viscosity characteristics:
Composition of Watch Oils in 1900
- Sperm Whale Oil: Widely used due to its exceptional stability and low tendency to gum up. It was prized for its ability to maintain lubricity over time and across temperature changes.
- Other Animal Oils: Refined oils from other animals, such as porpoise jaw oil, were also used in precision instruments.
- Vegetable Oils: Occasionally used, but less stable and more prone to oxidation and gumming.
- Mineral Oils: Began to appear as petroleum refining advanced, but were less common in fine watchmaking until later.
Additives
- Minimal to None: Additives were not commonly used in 1900. The concept of enhancing oil performance with chemical additives (like anti-oxidants or viscosity modifiers) was still in its infancy.
- Natural Refinement: Some oils were purified or filtered to reduce impurities, but this was more about improving clarity and stability than adding performance-enhancing compounds.
Viscosity Characteristics
- Low Viscosity: Watch oils needed to be extremely light to reduce friction in delicate mechanisms. Sperm whale oil, for example, had a naturally low viscosity suitable for escapements and pivots.
- Temperature Sensitivity: These oils could thicken or gum up over time or in cold conditions, which is why regular servicing was essential.
