|
|
Post by Arnie Benton on Jul 17, 2015 13:32:09 GMT -6
I've been trying different firing schedules and here are some crystals, still warm -    I don't know where all those 'growth rings' in the last picture come from - the program only has 2 holds - at 2000 and at 1900. I can also report that the 6 bowls in this firing had a 99% reduction in the amount of crazing. But they are still warm. If this wondrous result is still there tomorrow morning, I'll tell what I did. Arnie |
|
|
|
Post by tileman2 on Jul 17, 2015 16:18:34 GMT -6
Arnie: 1st, great looking crystals young man. Am more than curious about a few things I am seeing. The 3rd pic has a stucco type field effect in lieu of the normal solid field: intentional? I am seeing traces of a third growth ring in the third pic as well. Extra thick kiln walls with additional fiber board perhaps? Or the last pic was on the bottom of the kiln load? My main crystal kiln is extra insulated, resulting in much slower cooling; which also produces unintentional growth rings.( I do not pull bunges either) Year or so ago I started using tall kiln legs and placing a large shelf to cover the load under it. About three inches below the lid to intentionally trap heat under it and equalize hot/cold spots. Have you ever played with Imsil A-25 SiO2? Krueger Supply and Axner carries it. Think you will be pleasantly surprised at the clarity it produces, both in the field and in the crystal brightness. So now you have to fess up: you are a chronic experimenter like me. I am running a test this weekend: all four identical glaze mixes in the same kiln: only difference: four varieties of commonly used ZNO> my curiosity got the best of me. Perhaps it is time for you to do some branding: everyone knows Fenton glass, time for Benton plates. Good work lad.
Tom
|
|
Kuba
Full Member
SztukKilka in Old Formu
Posts: 111
|
Post by Kuba on Jul 18, 2015 6:52:37 GMT -6
Hi Arnie,
How big your kiln is?
|
|
|
|
Post by Arnie Benton on Jul 18, 2015 10:29:10 GMT -6
Tom -
I've used diatomaceous earth and amorphous silica. I'm not sure what the Si I'm using now is called -It's 325 mesh. You're right - the firing schedule included a very slow ramp from 2000 down to 1900. One of my kilns cools slower than the other - and I do what Koz suggests - programming a cooling ramp that evens them out.
Yeah, I do lots of experiments and have found that taking pictures works much better than trying to write descriptions of the results.
As to Benton brand - I've resisted selling my plates. I did open an Etsy site just to see what happens - I'd rather give them away to people who like them. I have much more freedom to 'play'.
Hi Kuba - both my kilns are the same size - 7 cubic feet - about 22 round by 27 inches high. They have different cooling rates and Koz's suggestion is the way to go - then you can eliminate cooling rate as a variable.
Arnie
|
|
|
|
Post by Arnie Benton on Jul 18, 2015 11:28:20 GMT -6
Here are the same crystals after striking -    The glaze in the first and second picture has Ru Cu and .1Co The 3rd picture has Ru IL Cu Fe and 2Ni. The .1Co seems to color the crystals more than 2Ni after striking. Arnie |
|
|
|
Post by jfox on Jul 18, 2015 11:57:33 GMT -6
there was a thread i started a couple of years ago called" controller instability" when i started to get lots of tiny rings (30 to 50)it was very nice, caused by the controller wandering up and down about 15 degrees unfortunately my controller died entirely shortly after that. i tried to recreate it by having an entire 2nd program that was just was just 20 degrees up and down which worked but never was as nice as the accidental one
|
|
|
|
Post by tileman2 on Jul 18, 2015 12:09:21 GMT -6
Jim:
What were the (symptoms) for lack of a better word of your controller starting to fritz? Curious to know, might explain something going on in one of mine. Replaced the thermocouple, that is off the list. Checked temp against the pyrometer, calibrated the thermocouple offset; getting these spikes in read outs and odd (for this kiln) growth.
Tom
|
|
|
|
Post by jfox on Jul 18, 2015 12:55:19 GMT -6
after that it started doing unexpected and unexplained shut downs so i replaced the board so i really never knew what was going on with it. the new board worked fine so never really figured it out
|
|
|
|
Post by sherri on Jul 21, 2015 16:45:29 GMT -6
Hi Dr. Arnie,
I'm so glad that you have fixed the crazing issue. My bet is that part of it was the silica and perhaps the amount of frit. I try to stabilize my glazes so they don't run so much through reducing the frit, zinc, and upping the silica and I rarely have any crazing whatsoever. Am I right? Or did you do some other doctoring....
|
|
