HEAT or TEMPRATURE? or....

[Havi]

Hi everybody,
One of my teachers told me one day "think heat", not "temprature".
Somehow I understood it as if the VOLUME of the heat is important, not only the temp.
i.e.,
Will there be a difference in firing results , if I fire AT THE SAME TEMPRATUE in a big kiln or a smaller kiln?

Quite hot now, here in Israel.
I need to cast / fuse a piece. It is going to be a long [relatively] process, about 50 hours.

I would like to use my smaller kiln to do the job. This way only my workshop will be hot, if I use my bigger kiln - the whole house will be heated - which will not be that pleasant.
Yes, I can't shut the workshop door... It must be at least a bit open.

Will there be a differnce in the cast piece???

Many thanks,
Havi

[Bert Weiss]

Havi

I once contracted to use a giant walk in sized car kiln. The entire kiln is made of bricks. The door and floor are one piece and slide back and forth on a railway. I did some kilncarving in it using 19mm glass. A firing to 1400ºF in this kiln did way more "heatwork" to the glass than a firing to 1500 would do in my fiber kilns. In my fiber kilns I have way more control in how I want the glass to look. There is a difference between the heatwork that gets done in the 2 environments in order to bring them up to a particular temperature. I do however believe that you must hit certain temperatures to get the glass to soften to a sticking point, for instance. So, there is a big difference in the heatwork that gets done in a slow or fast firing, or in a kiln with a large mass compared to a low mass kiln.