Friday, 12 April 2013

All fired up........

I greet bisque firing days with a mixture of relief, trepidation, anticipation and excitement.  There is so much that can go wrong, potentially wrecking weeks of work so I never, ever take anything for granted.

Today's full bisque firing is only the fourth since I installed a new set of kiln elements, so I'm still fine tuning the firing schedule, adjusting the top temperature and the soak time to hopefully achieve a perfect fire.

One of the joys of having a computer controlled kiln is that I can programme a time delay so that the firing can begin in the middle of the night.  This is especially helpful with a bisque firing which can take up to 10 hours, as I like to be around for the final, critical stages.

Today's firing took just 6.5 hours, due mainly to the relatively new elements.  As they age, firing times will gradually lengthen until eventually it becomes difficult to reach the top temperature of 1215 degrees Celcius.

Which is very, VERY hot!
The normal domestic electric oven reaches a top temperature of around 250 degrees Celcius, and if you've ever burnt yourself on an oven shelf you'll have some idea of just how hot that is......

This is a view of the kiln lid, showing a glowing line of white heat from the interior.

It is always a massive relief when the soak time is achieved, (that is the duration of time for which the kiln is held at the top temperature to allow the porcelain to properly mature)
the kiln switches itself off, and the display shows.......

However, I will have to wait at least 12 hours before the kiln will be cool enough to open, so tomorrow morning I will discover what has happened inside.

Hopefully, when I lift the lid I will find perfectly fired porcelain bisque...... *fingers firmly crossed*


1 comment:

Debbie said...

Hoping alls gone well and there's been no mishaps.