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cone 10 electric/sam h.

updated fri 8 apr 05


Craig Martell on thu 7 apr 05

Sam was wondering:
> Any other ideas for prolonging the life of a high-fire electric kiln?

Hello Sam:

The only other thing I can think of is sufficient insulation. I've used
kilns in the past that had only 2.5 or 3 inch thick walls and they really
struggle to get up to cone 8 and above. If there is sufficient insulation
to cut heat loss the kiln will fire in a reasonable amount of time and this
will give the elements a break.

I rebuilt an Olympic oval many years ago. It was rated to cone 8 but
didn't function worth a damn. I had to remortar and repair the lid. I
made fireclay buttons and put 2600 degree fiber on the lid hot face and
buttoned it and fastened the buttons with 13 guage Kanthal. I wrapped the
lid with quarter inch aircraft cable and tightened it with turnbuckles
instead of those wimpy hose clamps. I added Insblok 19 to the outer walls
and totally rewired the kiln. Got rid of the interbox plugs and hard wired
everything to get as much electrical potential as possible and cut
resistance to all the load lines. This made a big difference in the firing
of the kiln and my pots came out much nicer. All of this was suggested by,
guess who, Kenny Simpson who was also the dude who wound elements for
me. I think he's real glad that I fire reduction now! 8>)

later on, Craig Martell Hopewell, Oregon