I have stored moulds in toolboxes with silica bags and sometimes vpi stuff. I notice that moulds stored on my desk will get flash rust in the bottom of the cavity, like moisture sinks and condenses during daily temperature swings.
I didn't like to oil them die to required cleaning before use but now I am considering it. I found on the Noe site to scrub with dawn and then preheat on a stove. This has worked well.
Use of slip 2000 degreaser before heating worked too well and resulted in flash rust in 10 minutes. Thoughts? Thanks