Vermiculite

It seems most members on this forum are living in the states of America where vermiculite is not readily available in sheet form.
I think this is unfortunate due to it versatility and ease of use to work with.
From my own experiments it can last for many years, however I tend to stick to smaller size systems that dont often exceed 8-900f
In my 6” J tube the vermiculite will last at least two seasons even in the loading area of the fire box.
In my vortex stove it has lasted for many years in the hottest parts of the stove where the temperatures are constantly over 1000f.
What is does not like is moisture or being used in large pieces.
The beauty of the board is how quickly you can build a prototype or experiment and how easy it is to work with.
I think it would have limitation if building the larger batch box stye stoves that get extremely hot mainly because it does not like to be used in big slabs.
Anyway here is a little experiment I did a few month ago…

Any plans to try some mixes with fireclay to see if you can get closer to replicating that strength?

Hi Phil, that would be fun.
i have found a very useful mix for use in pizza ovens just by mixing in some silica sand, one part cement, two parts silica sand and two parts vermiculite. That makes a strong mix but is not particularly insulating or lightweight
I think the commercial board has some type of binding agent as well as clay but I really dont know what it is.

Interesting experiments - thankyou!

Fox James wrote:I think the commercial board has some type of binding agent as well as clay but I really dont know what it is.

Something that chemically bonds to both the vermiculite and the clay...