[Claybot]

Hi. Although I've been making things out of clay for years, I'm new to using a kiln myself. I'm trying to use an old but seldom-used kiln to fire my pots and I'm having problems. I underglazed my greenware pot and fired it to 04. The pot became bisqueware, but the 04 underglaze can be wiped off with a moist cloth. The 04 witness cone I put in didn't bend all the way down, only a little - if the cone base is 6:00 on a clock, the tip is pointing at 2:00.

Here is a photo of my Olympic Kiln with kiln sitter.


I was told I need to calibrate my kiln sitter with this device, a calibration tool about the size of a quarter.




I have no idea how to use that tool to calibrate the kiln sitter. The tool is not mentioned anywhere in my manual. Can somebody help me out?

Thanks for any help you can provide.

[Dharsi]

Claybot, on 19 May 2012 - 08:11 AM, said:

I have no idea how to use that tool to calibrate the kiln sitter. The tool is not mentioned anywhere in my manual. Can somebody help me out?

Thanks for any help you can provide.

Youtube baby! There are a gajillion videos on how to do just about everything pottery. Here is one and there are many more. I hope you can find one that will help you solve your problems.

http://www.youtube.c...h?v=5Pul7fEeOOE

[Claybot]

Thanks for the reply. I have a watched a few YouTube videos now, so I have a fair idea what I need to do.

I'll update this thread later, hopefully with good news.

[Arnold Howard]

Claybot, on 19 May 2012 - 07:11 AM, said:

I underglazed my greenware pot and fired it to 04. The pot became bisqueware, but the 04 underglaze can be wiped off with a moist cloth. The 04 witness cone I put in didn't bend all the way down, only a little - if the cone base is 6:00 on a clock, the tip is pointing at 2:00.

The 04 cone, at 2 o'clock, is probably only a few degrees in temperature away from full maturity.

In case you used a self-supporting cone (with the built-in base), the cone has reached maturity when the tip is even with the top of the base. It is over-fired by a few degrees when the tip touches the kiln shelf.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com

[Claybot]

Whoa, thanks for anticipating my questions before I asked them, Arnold! I was going to make a post about witness cones.

By the way, THE CALIBRATED KILN FIRED PERFECTLY!

Well, maybe it fired a little too hot, as the tip dropped lower than the top of the base, but that's better than not hot enough! And it did not bend all the way to the bottom.

Incidentally, this was the best YouTube video I found on the subject of calibrating the kiln sitter with a gage: http://www.youtu.be/...feature=mh_lolz

Happiness is a properly bent witness cone.