Friday, 20 October 2017

The temperature's rising.....

Firing days are always a bit fraught.  So much could go wrong but I'm now beyond the point of no return so I just have to wait it out.

I set the kiln to switch itself on at 5am this morning.  It's currently showing.....

So, only around another 80 degrees Celcius to go till it hits top temperature.  Then there's a 15 minute 'soak', holding the top temperature to complete the maturation/vitrification process in the kiln.

That's the most nerve-wracking, nailbiting bit, as I have no idea what's actually happening in there.

I do know it's VERY HOT... the heat is percolating through the rest of the house.  I could feel it as I came downstairs this morning... increasing in intensity as I went through to the dining room, where my kiln resides.

I also know it's VERY HOT as the tiny gap between the body of the kiln and the lid looks like this....

So, yes... that's WHITE HEAT inside.

Like I said.  VERY HOT.  Unbelievably hot.  Almost five times hotter than the hottest setting on a domestic oven. 

Really, very, very burny.

It will now struggle to reach the top temperature and hold the soak time... I estimate maybe another hour or so, at which time it will switch itself off and very gradually, over the coming 24 hours, cool down sufficiently for me to open the lid and view the bisque fired contents for the first time.  

So, what could possibly go wrong?

Loads... that's what.
  • Despite my careful, meticulous placement of each tiny piece, on a bed of firing sand, some of them may have shifted, and during the intense heat, if any of them touch each other, they may meld together.
  • I may have miscalculated the firing schedule and everything will be slightly underfired.  In this scenario the pieces will look a bit chalky as they won't have fired to maturity.  Although annoying, this isn't disastrous I can refire them.
  • Worst case scenario, I have miscalculated the firing schedule and everything will be catastrophically overfired and irredeemable.  The pieces will be shiny and blistered... in a runaway overfiring they will actually melt into each other and onto the shelves. 
  • Even worse than an overfiring, one of the shelf supports might fail, dropping the shelf it's supporting onto the ones underneath.  This wouldn't just ruin the pieces, it would completely ruin my kiln too.
Hence the nerve-wracking, nail-biting period before I can finally open the kiln tomorrow morning.

It's going to be a l-o-n-g day.  *sigh*

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