Just wondering if I need to get rid of my hard wood ash in favor of vermiculite? Also, is it true that not all steels benefit from resting steel to cool in vermiculite/ wood ash/ sand? Thank you for your time!
Brandon
There are so many variables to the answer to that question, it's difficult to put into words.
When you consider the word "benefit" in your question, you first must determine why you would want to slow cool it in the first place. And from what temperature. And what steel. And what your subsequent steps will be.
I slow cool nothing in my shop.
Karl B. Andersen
Journeyman Smith
Vermiculite is a better insulator, but I would just eliminate lamellar annealing. lamellar annealing is the process of slow cooling from over non-magnetic temperatures to produce lamellar carbide, or pearlite. It is time consuming, does not produce the most machinable condition, and is indeed bad for steels with an excess of .83% carbon. Subcritical annealing (spheroidizing) is quicker, produces more machinable steel, is safe for any carbon level, and no need for vermiculite or wood ash, just a heat source.
"One test is worth 1000 'expert' opinions" Riehle Testing Machines Co.
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Vermiculite is a better insulator, but I would just eliminate lamellar annealing. lamellar annealing is the process of slow cooling from over non-magnetic temperatures to produce lamellar carbide, or pearlite. It is time consuming, does not produce the most machinable condition, and is indeed bad for steels with an excess of .83% carbon. Subcritical annealing (spheroidizing) is quicker, produces more machinable steel, is safe for any carbon level, and no need for vermiculite or wood ash, just a heat source.
Does Howe do furnace cooling compare?
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Does Howe do furnace cooling compare?
Not sure I understand the question,
"One test is worth 1000 'expert' opinions" Riehle Testing Machines Co.
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Not sure I understand the question,
sorry about that I wrote and posted my last comment without proofreading it (blushing emoji here) how does vermiculite compare to just heating a blade up to above critical and letting it cool slowly in a propane forge. I read about furnace cooling in Dr. Verhoeven's book and I may be wrongly applying this term to this type of kind of annealing/softening and tend to use it that more than my vermiculite bath.
also, what happens with vermiculite or ash cooling with a steel of .83% or more?
