This is what comes to my mind about ramping up to the annealing temperature when I think of doing a batch anneal run.
How much time would I take to get a rod of glass hot in the flame if that rod was as thick as the beads I am bringing up to annealing temp?
For me the answer is not a whole of time. Not instantly because that leads to frit on a stick and popping hot glass that we all are familiar with but pretty darn quick in the overall scheme of things.
I don't batch anneal but I would use the fastest speed my kiln provides to get 'up' to temperature. It will never be near as fast as a hot torch flame between the warming of the interior of the kiln and then the eventual soaking of heat into the inside of the bead.
I think the next question is how long to soak the beads at the annealing temperature to ensure that the heat gets into the core evenly.
I don't know that answer specifically but I would soak them for at least an hour once the kiln gets to the annealing temp.
If the volume of glass of all the beads was anything larger than a pack of cigarettes then I would double that time just to make sure that every single bead got to the annealing temp at its core.
Then I would follow Marks chart to bring them back down to room temp.
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