Lon Williamson wrote:
Not only that, but I've seen old grease separate in the container.
It kinda turns into oil and a more viscous grease. If something like
that is used in cameras or lenses (I'm not sure it is), it would really
gum up the works with age.
-Lon
Grease is just oil mixed with soap. Repeated, slow, heat cycles will
cause separation. Normal soap is based on sodium stearate; if you use
calcium stearate you get calcium based grease, lithium stearate gives
you lithium grease. Each gives the grease different properties.
Discussion of the detailed chemistry and additive packages could keep us
going for a while......
Jostein wrote:
The remedy is almost certainly relubrication.
Greases change properties over time and become harder. In addition,
they can accumulate particles, both from the environment and wear on
the mechanical parts. Most such particles will be more partial to
moisture than the grease itself, and thus impact the low-temperature
performance.
