I woulda give ya a freezer
I have a safety concern with your build. A good friend who is an experienced builder and home inspector once told me that fans and rheostats are a hazard. I looked it up, and there is a specific type of controller that is used on variable speed fans. Otherwise it is a fire risk.
Take a look at this yahoo answers thread.
https://answers.yahoo.com/question/index?qid=20100723131008AAlILj9
It might be worth leaving the settings untouched, and graphing the temp/humidity every 30 minutes over an 8 hour period. My impression is that the higher the Watt setting of the Crockpot (Low, Med, High), the greater the swings in humidity. The high setting may actually boil some water, by the time the kiln temp reaches the set point. Your insulation is so good that a lower Watt setting may do well, and may stabilize the humidity (perhaps even with no lid in place).
Plan B is a cup a rock salt.
Bob
[Knucks thinks my tool selection is archaic. Does that qualify as on-line bullying?]
I just got promoted to chief kiln inspector (CKI). I will be down in 2 weeks to inspect it. There has been a policy change this year though. Payment is now expected in cigars, wine and women..
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