Re: Storing Your Leica Camera & Lens: Best Practices
Push1stop wrote:
Out of curiosity were the lenses that had weak springs older lenses pre 1980/1990's ?
I'm not a metallurgist but I believe what wears springs out is not from them being stored compressed or fully extended, what wears springs out is the actual act of it being cycled (compressed and released).
My understanding/knowledge comes from my extensive gun smithing courses, tests, and work with springs in that realm... so even tho the apparatus is changed, both firearms and lenses utilize springs. AS LONG AS THEY WERE CORRECTLY HARDENED/MANUFACTURED they should be able to be stored in either position.
We've done tests to see how long a firearms magazine (which is under spring tension) can be stored fully compressing the spring. After 20 years the difference between a new spring and a compressed/stored spring was extremely minimal if at all where as a magazine that was loaded/unloaded over it's lifetime the difference between new and old became much more apparent.
I am not a metallurgist either and I am some random guy on a forum giving out advice for free so that must be taken into consideration. Metal fatigue is another factor, but that's another topic. If you did your own experiments, then you are ahead of me as I never did any such experiments. However, that advice about springs has been consistent from spring manufacturers for whatever purpose they are used whether that is a torque wrench or a lens aperture.
To avoid spring weakening due to creep, minimize stress on your springs whenever possible. Do not leave your springs under constant compression unless this is required for them to do their job. Do not subject them to high temperatures if it can be avoided. If your springs are in conditions that are likely to lead to creep, be sure to check them regularly and replace them when necessary.
That is one source, but I have seen this general advice everywhere a spring is used. You may be right that it might make little difference if the spring was correctly manufactured and sized for the application.
Jan 13, 2024 at 05:42 PM
Previous versions of cbass's message #16442831 « Storing Your Leica Camera & Lens: Best Practices »
