William Bronson wrote:
-The standard batch box length can be stretched by -how much again?
25% longer is the official stance on that question.
William Bronson wrote:
What if core was sitting on the bottom of the bell?
I suppose the blocks, being only 4" or so thick, would not be a safe air gap?
What about a standard size hollow brick?
Are these blocks too porous and not heat resistant enough to use in any part of a bell?
If the core was sitting on the bottom of the bell, it would conduct heat down into the floor. Would big hollow blocks be enough to keep the wood floor from being damaged? IMO, likely because of the sizeable air gap. But would those big hollow blocks be damaged by the direct heat conduction from the core above? Also maybe.
Depends on if the core was insulated on the bottom at all, which you could do with ceramic fiber board or vermiculite board (since ceramic blanket would compress under weight.) Safe building practices like elevating the core help eliminate the maybes since nobody wants to find out the hard way!
William Bronson wrote:
Are these blocks too porous and not heat resistant enough to use in any part of a bell?
From all my reading up it would seem that you COULD use cement blocks in the lower parts of a bell. But they are not the best material since they do not store heat like clay brick. And even then may not stand up to the thermal cycling over time. Solid cement blocks being much better than hollow but still not great. You could NOT use them above the core exhaust unless you are using the appropriate "double skin" method where the inner layer of the bell above the core is refractory material like fire brick.
I know you know these things but I'm playing along with idea of discussing it out loud for others to read :)