Modifying a inexpensive temperature probe is an awesome idea. I'll get
after that, in the meantime what is the optimum core temperature,
compared to ambient seasonal temps? I was thinking a wood chip and
sawdust compost pile of sufficient size could at least reach 100
degrees Fahrenheit.
Llke you say, the core temperature needed depends on what the purpose
of the pile is. It seems like every project is as complex as we can
imagine. My goal right now is to get the shell of my new shop up
before Winter, once I have a more comfortable place to work, I will
bring my old International Harvester Utility 460 indoors and finish
retrofitting the frontend loader to it. If all goes as imagined, which
I know is a lot of "ifs" next year I will be able to stir giant
compost piles made from forest management by-products.

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energy and passive solar designed workshop progress.