Newbie....WHY & HELP!

Cathy Crain · Post by **Cathy Crain** » Sat Jan 10, 2004 11:53 pm

The attached photo is my very first fusing.
(this is also the very first time I have attempted to send a photo....I hope I didn't send the entire web site.....OOOOOPS)

I did a test of about a dozen squares around 2" x 2"...all BE glass. Bottom was black irrid., top was clear with green horse & dic. frit on top. I used the fusing schedule for "your first little tile

" 600/hr to 1100, 250/hr to 1300, 800/hr to 1500 (hold 10 min.), cool to 1050, then 200/hr to 750

My kiln is a Skutt GM 1227 and I was only firing on one shelf approx. 6" from the bottom. The Environvent was on the entire time.

QUESTION:
1. What caused the ghost line around the entire horse?

There were 3 tiles that had this same little horse figure.
a. the one shown,
b. a trans. purple on top of 2 layers of clear,
c. a trans. dark brown on black irrd.
The one shown on the photo is the only one with the ghost line.

2. Originally, the little horses were very crisp in shape. The one shown & the purple on clear really flattened out and lost their shape. The trans. brown on black irrd. changed somewhat but not nearly to the extent the others did. Is this a "hard glass" vs. "soft glass" problem? Or is it the Gods screwing with me?

http://www.craindesign.com/crain/crainw ... seTest.jpg

Thanks (this site is fantastic),
Cathy

Brock · Post by **Brock** » Sat Jan 10, 2004 11:58 pm

That ghost line is the vertical face of the edge of the glass, after melting down. For some reason, closely related to devit, I think, the edge of the glass acts differently than the face, or top, of the glass. Brock

Ron Coleman · Post by **Ron Coleman** » Sun Jan 11, 2004 12:13 am

I'm not siure what BE glass the green is, but it looks like the edges turned frosty from sawing and didn't gloss up during fusing.

Did you cut the green piece on a ring saw? They tend to give a very rough finish and may cause devit on some glass. Edge cleaning may also be an issue. The sawn edge must really be scrubbed and even then they might devit.

Try another sample oif the green glass with just a cut edge (not sawn) and see what happens.

Ron

Cathy Crain · Post by **Cathy Crain** » Sun Jan 11, 2004 12:32 am

Since this ghost line did not show up on the other two horse images, is this a problem related to this specific glass, or is it a temp. problem?
Could it be removed?

I was experimenting to see how the glass held its shape and detail. My first results seem to indicate that it was a free for all. Am I correct in assuming that there is a wide range in 'hardness' and stability in different glass (sorry is this sounds stupid, but new inquiring minds want to know)?

Thanks

Brock · Post by **Brock** » Sun Jan 11, 2004 12:39 am

You could, after cleaning those cut edges extremely well, overglaze the horse. The resulting piece, while not devitting, will still have that appearance of a border. There IS a wide range of hardness, (viscosity) amongst glasses, enen from the same manufacturer. Brock

Tony Smith · Post by **Tony Smith** » Sun Jan 11, 2004 12:39 am

It's a combination of glass and temperature. Your temperature was high enough for a flat fuse with each of the glasses that you used.

Take your temperature down to 1450 and experiment with your hold time... you'll get much more definition in your horsies.

Tony

Cathy Crain · Post by **Cathy Crain** » Sun Jan 11, 2004 12:41 am

Thanks Ron,
Yes it was cut with a ring saw....I will try an experiment with the same glass as you suggest and see what happens. I may not have gotten it as clean as the other two images which were both cut with the saw.

Thanks Brock,
I never thought about the edge...duh, so much to learn and so little time!

Ann Demko · Post by **Ann Demko** » Sun Jan 11, 2004 11:30 am

Cathy, My first project also had the cloudy ring around the design elements. My elements were fused to a colored back and capped with clear. It was a great piece, for my first, but the scummy edges around the design elements drove me crazy. I had not cut them with a ring saw, because I didn't have one at the time. I had ground the edges with my grinder that had a well worn diamond grinding head. Anyway to make a long story short, I went on and finished the project, accepting the fact that it would be a bowl only a mother could love. After firing again to correct a large bubble, I still had the scum. Slumped into bowl form and wha-la no more scummy edges. Don't know why but I assumed the repeated firings finally broke down the edges and allowed them to flow giving the smooth clear edges. Not very scientific but another story of how the kiln gods really have control. Ann