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Avoid burning off enamels

Posted: Sun Dec 16, 2012 4:04 am
by S.TImmerman
A very good friend sent me several bottles from the naval academy where our husbands went to school prior to flight training. The bottles all have enamel on them and she has asked me to make a couple bowls out of them. I have cut the bottles into rings and would like to know if anyone has a temperature they could share that would fuse the rings to stick together and not burn off the enamel. I could do a test on my small kiln but worry that it's. Temperature might not be the same as my clam shell. Any suggestions would be greatly appreciated .
Ty!!

Re: Avoid burning off enamels

Posted: Sun Dec 16, 2012 4:01 pm
by Barry Kaiser
Enamel is a word that has many meanings. Even vitreous enamels vary all over the map.
If you do not know the specific enamel, the only way to determine the maturing temperature is to test.

Once you determine the maturing temperature in your small kiln, you are most of the way to figuring out the temperature in the large kiln. I use a rule of thumb (that is by no means guaranteed to work) of dropping the top temperature by 50 degrees for the maturing temp in a much larger kiln.

Re: Avoid burning off enamels

Posted: Sun Dec 16, 2012 4:31 pm
by rosanna gusler
they will either work or they will not. not really anything you can do about it. just fuse them as cool as you think you can get away with and beware that they probably contain heavy metyals. rosanna

Re: Avoid burning off enamels

Posted: Mon Dec 17, 2012 5:34 pm
by Judd
My experience with newer bottles- all the cool colors are organic paint, and the firing, you get ugly white blobs. Lay your rings together and cook those babies. I usually fire float/bottles around 1525.

Re: Avoid burning off enamels

Posted: Mon Dec 17, 2012 6:53 pm
by Mark Wright
I had a similar request to slump a very pretty red wine bottle. It was disaster. I think the "paint" caught fire. All I know is I saw the kiln smoking and shut it off. When it cooled everything was black. Not a fun clean up job.

Re: Avoid burning off enamels

Posted: Mon Dec 17, 2012 11:54 pm
by KaCe
@ Mark,

How did you clean up the soot?

KaCe

Re: Avoid burning off enamels

Posted: Tue Dec 18, 2012 12:31 am
by Don Burt
Barry's first comment "Enamel is a word that has many meanings. Even vitreous enamels vary all over the map." implies that not all enamels are vitreous. Many bottle decorative coatings are organic systems and are not designed to be heated over a couple hundred degrees. If yours incinerated into soot, they're not vitreous.
You might read through the stuff on the Ferro site for an idea of range of coatings.

http://www.ferro.com/Our+Products/Color ... Container/

Didn't see Judd's comment above until I had posted this. Yeah: what Judd said.

Re: Avoid burning off enamels

Posted: Tue Dec 18, 2012 2:50 pm
by rosanna gusler
KaCe wrote:@ Mark,

How did you clean up the soot?

KaCe
soot clean up is easily accomplished by firing the kiln, vented to over 1000f. self cleaning oven. r.

Re: Avoid burning off enamels

Posted: Wed Dec 19, 2012 12:02 pm
by Mark Wright
KaCe wrote:@ Mark,

How did you clean up the soot?

KaCe
I did some light sanding, vacuuming and then a full fuse cycle. The kiln looks fine. The vermiculite kiln shelf was a little tougher. It required sanding to remove the "black" and the kiln wash.
Mark