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View Full Interactive Version Of This Page : The Lunesse Cracked Aurora/silver Thread, part 2.


lunesse
2009-02-22, 1:24pm
That one is a couple years running and old now, and I received a revelation this morning, so I am just updating for anyone who even cares anymore. ;)

I went to dear Kalera's house this morning and bummed her pyrometer, came home and stuck it in the kiln. (Caldera).

When my kiln read 970, the pyrometer read FREAKING 800. 800???

Kalera said she had heard of kilns that were off by 100 degrees, crazy crazy. This is way crazier.

I upped the kiln program to 1100. The pyrometer reads 940, the very bottom end of what Bullseye glass likes.



Ok, so maybe this huge mystery is solved. But....how did all my other beads, the ones without silver leaf, survive at such a low temp? That almost makes me not believe it could possibly be THAT off, because wouldn't everything die, shouldn't all the bullseye beads crack if they were sitting at 800 ish for the past year plus?

???????

And what do I do now? Can you reset a Caldera? I know I can just run it at pretend 1100, but I would really rather know where I am really at.

I'm going to go out there and make beads at "1100" right now and see what they do, survive, or flatten out on one side on the shelf.

LyndaJ
2009-02-22, 3:27pm
I'm so glad you got an answer finally!! But off that much, is crazy. I'm surprised you didn't have more trouble, too.

Sorry I don't know how to fix it, though.

PaulaD
2009-02-22, 3:41pm
Maybe it has PMS and is only off certain days of the month??
Paula

squid
2009-02-22, 4:24pm
You should just need to buy a new thermocouple. Mine was off by over 150, so I am not at all surprised by your results.

squid
2009-02-22, 4:25pm
Oh and btw, mine is STILL off by about 125 degrees - I just learned to adjust.

gubnavnania
2009-02-22, 4:50pm
Ok, so maybe this huge mystery is solved. But....how did all my other beads, the ones without silver leaf, survive at such a low temp? That almost makes me not believe it could possibly be THAT off, because wouldn't everything die, shouldn't all the bullseye beads crack if they were sitting at 800 ish for the past year plus?



Not always crack. It's the same way when I didn't have a kiln before. I put all my beads in heated vermiculite before send them to someone for batch annealing. All my earlier beads (wonky, testing new stuff and colors) when I started are still intact and none of them are anneal.

I'm glad you found out the reason :D

Heidi von Frozenfyre
2009-02-23, 11:04am
On the face of the temp guage there will be a small set screw under the dial face. It's very small. *That* is what you need to be turning ever so slightly to calibrate your kiln.

Next... I predict that there will be many latent breaks using any of the silvered colors. When I was producing color in the Czech Republic we were incorporating silver and golds into the pot - heavy metals are fine for the most part, but they are really not compatible with the coe of glass. After a while they will crack unless the lead content is has made the coe over 130. It might be 5 years, hopefully by then the bead artist will have a different phone number. Sorry to be such a pessimist. Been there, done that.

lunesse
2009-02-23, 1:45pm
well fortunately I do not have many things made with silvered colors, or if I did, very little of it.

Thanks for the info on calibrating, Heidi!

p.s. all beads from yesterday survived and were not overheated to slumping. woo!