crap

[dragonfly designs 56]

I forgot to put a piece of charcoal in my kiln so I dont loose my silver effects. Can you reanneal them with the charcoal, or am I just screwed? Two solid days of bead making with silver. STUPID EXPENSIVE MISTAKE! Any help would be greatly appreciated.

[gemsinbloom]

Are you referring to silver glass? Why would you need charcoal? I must be missing something here...

[houptdavid]

http://envisionsf.blogspot.com/2009/...mperature.html

[kbinkster]

Is your kiln oxidizing, Kelly?

[dragonfly designs 56]

My silver colors are dulling and Im loosing the irridescence on the beads that are not encased. Im not loosing it all, but enough to be disgusting, lol. I will have to look, for some reason I think Im at 950 garage temp. will have to check and let you know. I dont know what you mean by if my kiln is oxydizing, sorry

[kbinkster]

If it has air circulating in it, particularly in the last few hours of the program, it is oxidizing.

Check your kiln temperature, too. I thought that mine was fine, but when I started annealing silver glass beads, I had a little trouble with my colors washing out. I read that Squid had a kiln whose temperature was way off (I think that was you, Squid). I had an extra digital controller with a pyrometer and decided to check my kiln's temperature. It turned out that my controller was off by as much as 100° F at my garaging temperature and 60-70 degrees off at the strain point. That's a lot to be off! I adjusted my program accordingly and have had much better results ever since.

I don't know if you can run the batch again with a reduction atmosphere in your kiln (charcoal), but if you try, the worse that would happen is that nothing would happen, right?

[dragonfly designs 56]

yes, I agree. I broke the fire brick in my bead door, but I have it propped in there. Thing is, they really dont look any different than when it wasnt broken. Weird thing, some of the silver survives....btw, what kind of charcoal again? Is it the kind you use on your charcoal grill, or like fish tank charcoal? I will also let you know the results, maybe someone can use the advice as well. I will take before and after pics using Kevans photo tutorial which Ive learned tons from just reading the first couple of pages. On my list of to do items sometime today.

[Mitosis Glass]

Fish tank charcoal, apparently. I haven't tried it but that's what I remember reading.

Sorry you had this happen. It sucks when all that work and glass come out looking like poo.

[dragonfly designs 56]

thanks all. will try it and let you know how it wrks out

[playswithfire104]

Try annealing at 920 instead of 950.

[Carolyn M]

You can re-anneal, but I don't think it will have any effect.

You only need a spoonful of the charcoal in a little bowl

[TinaJ]

Could this be my problem, too? When I have made beads with double helix psyche and gaia glass and it looks blue and purple when I'm torching (out of the flame and over my AUR92s so I'm not looking through the color of the eyeware filter) but comes out greens and tans after annealing? Guess I need to do some more research....
Tina

[Seasoned Soul]

Originally Posted by TinaJ

Could this be my problem, too? When I have made beads with double helix psyche and gaia glass and it looks blue and purple when I'm torching (out of the flame and over my AUR92s so I'm not looking through the color of the eyeware filter) but comes out greens and tans after annealing? Guess I need to do some more research....
Tina

This happened to me and I haven't picked up psyche again...well not until I do a little more research.

[kbinkster]

Originally Posted by TinaJ

Could this be my problem, too? When I have made beads with double helix psyche and gaia glass and it looks blue and purple when I'm torching (out of the flame and over my AUR92s so I'm not looking through the color of the eyeware filter) but comes out greens and tans after annealing? Guess I need to do some more research....
Tina

Gaia strikes in a reduction flame. Psyche reduces.

A couple of different things could happen. If your temperature is too high, or they are garaged for too long, the struck silver crystals continue to grow larger, thus changing the color.

The other possibility is that if your kiln has too much oxygen inside, it reverses the reduction effects of any unencased reduced glass (much like how you would erase the reduction effects with an oxidized flame).

If your glass is encased and goes into the kiln with colors that you like, but comes out with something else, I would suspect that it is an issue with the temperature or the length of time it is held in the kiln (both are striking issues) and not a kiln atmosphere issue.

[Seasoned Soul]

Thanks for that info Kimberly... much appreciated

[ben david]

Originally Posted by kbinkster

Gaia strikes in a reduction flame. Psyche reduces.

Let's keep our terminology straight.

Striking has only to do with molecular changes caused by the temperature and speed of heating/cooling - components of the glass fall out of solution (like sugar that comes out of tea as it cools) or change their molecular structure. Striking is not a surface effect - as you can see in opalescent, aventurine, and milk-white glasses, where molecules precipitate throughout the glass.

Oxidation and Reduction refer to taking/adding oxygen molecules at the surface of the glass. Burning charcoal or other substances "steals" oxygen from the atmosphere, producing a "reducing" atmosphere with little free oxygen. (BTW you should be able to use anything combustible - in furnace glassblowing we toss sugary sweets and cardboard into the glory hole. Anything that burns.)

Obviously heat influences the speed/extent of chemical reactions like oxidation/reduction. But you do NOT need an oxygen-starved flame to make glass strike.

Ben David

[kbinkster]

Originally Posted by ben david

Let's keep our terminology straight.

Striking has only to do with molecular changes caused by the temperature and speed of heating/cooling - components of the glass fall out of solution (like sugar that comes out of tea as it cools) or change their molecular structure. Striking is not a surface effect - as you can see in opalescent, aventurine, and milk-white glasses, where molecules precipitate throughout the glass.

Oxidation and Reduction refer to taking/adding oxygen molecules at the surface of the glass. Burning charcoal or other substances "steals" oxygen from the atmosphere, producing a "reducing" atmosphere with little free oxygen. (BTW you should be able to use anything combustible - in furnace glassblowing we toss sugary sweets and cardboard into the glory hole. Anything that burns.)

Obviously heat influences the speed/extent of chemical reactions like oxidation/reduction. But you do NOT need an oxygen-starved flame to make glass strike.

Ben David

Thank you, Ben, for your kind and generous correction.

I am aware of the differences between oxidation/reduction and striking and that they are two different processes. I must have misunderstood the manufacturer's description of Gaia:

This rich green glass strikes easily in a slightly reducing flame, while remaining clean in a neutral or oxidizing flame. Upon striking, Gaia can produce surface coloration ranging from blues to greens and creams. Heavy reduction can yield red streaks, while very heavy reduction can develop a metallic iridescence.

I'm pretty sure that Double Helix knows the difference between striking and reducing, too. So, either "striking" is a misnomer used to convey the idea of "changing color" (which could very well be the case) or, they actually mean that the glass strikes in a reduction flame (which is in and of itself a misnomer of sorts, since the flame is not in reduction since it is trying to grab oxygen from the glass, and is therefor oxidizing, but we have gotten into the habit of naming the flame according to what it is doing to the glass and not it's own chemical description, but that's beside the point - well, except that we're discussing common glass misnomers) and further surface sheen are achievable with more exposure to a fuel-rich flame.

[squid]

Originally Posted by kbinkster

If it has air circulating in it, particularly in the last few hours of the program, it is oxidizing.

Check your kiln temperature, too. I thought that mine was fine, but when I started annealing silver glass beads, I had a little trouble with my colors washing out. I read that Squid had a kiln whose temperature was way off (I think that was you, Squid). I had an extra digital controller with a pyrometer and decided to check my kiln's temperature. It turned out that my controller was off by as much as 100° F at my garaging temperature and 60-70 degrees off at the strain point. That's a lot to be off! I adjusted my program accordingly and have had much better results ever since.

I don't know if you can run the batch again with a reduction atmosphere in your kiln (charcoal), but if you try, the worse that would happen is that nothing would happen, right?

Yep, that was me - my kiln was over 125 degrees off. Very frustrating until you figure out what the issue is.

[squid]

Kelly, just thought you might want to make your thread titles a little more descriptive of the topic. I didn't read this thread because "crap" didn't seem all that interesting to me.

[ellyloo]

Some will bloom with different colours when cooled, and waved through a little reduction flame, but if you do more, you will get a metallic sheen (also pretty). Sooo.... it's sort of both at the same time.
(that was in response to the terminology thing)

[BeadBrain:)]

Now see - the title "crap" must have been interesting enough for me to click through to...

Go figure. haa!

[lldesigns]

I keep my silver colors from changing by running the kiln cooler and annealing for a longer time.

[Pia Kaven]

Ok, and as a newbie to silver colors, I do not want to high jack the thread, but can somebody tell the difference with silver glass and silver glass?
When I first met this term, I assumed that it looks like silver, and then I realized that it could be color that has silver in it. Can somebody give me the proper terms, so I would know which one I am talking about at any given time?
Are the silver looking colors reducing, and the colors with silver in them actual silver colors? Help!
I would love to have some of the silver looking ones to my hands, but havent been able to figure out what to buy. And the colors with silver in them... well, just havent been able to afford them yet.
Thanks!

[bousky]

Good info here! Thanks

[Firebrand Beads]

Kelly, have you tried reducing your beads at different temperatures and seeing if they hold their effects differently in your kiln? This works for me with Taxco, and this is a quick way to try this experiment:
1) make 3 small spacer beads of your reducing glass. Melt them in smooth and cool to their regular (hot) color.
2) reheat all three to red hot, from right to left, one at a time -- so that the first bead is losing it's glow by the time the third one is back to red hot.
3) just as the last bead is red hot, turn off your oxy, UP your gas to a dragon's breath flame (visual gap between torch face and massive flames) and reduce the three spacers in the bushy part of the flame. They should shine right away.
4) put into the kiln at your regular anneal temperature and time and run the cycle. OK to do this at the end of your work time. Or, really test it hard and start your work cycle this way, garage them while you work and anneal them.
5) when cooled, compare how well the beads retained their effects in the kiln. Reduction happens faster and deeper when glass is hotter, and it may last in the kiln better when the reduction is more than one or two molecules thick.

When I do this experiment with TAG Taxco, they all three go into the kiln with a nice mylar finish, but the one that was already cooled to blue when it was reduced is back to that same turquoise blue after the kiln, and the one that was red hot is more muted than when it went in. However, the one that was a low orange glow when it was reduced looks just as shiny and metallic coming out as it does going in.

Anyway. It won't cost you anything you don't already have to try that experiment. FWIW...

And Pia - There are lots of threads here about the silvered glasses, and once you read them you will have an entirely new set of questions, lol! But the glass that looks shiny and silvery on the surface is generally a reducing silvered glass, meaning you reduce the oxygen in your torch flame to get the effects; and the ones that go all rainbow on you are the striking colors, those are also silvered and they are changed by cycles of heating and cooling.

[Pia Kaven]

Thank you Jenny, I think I got it now, that explained it well to me. I know there are probably tons of threads about it, but I just seemed to get the threads about the striking ones, since I didnt know the right terms. I really appreciate your help!