Flame annealing to prevent cracks? help a newb!

[pam]

Originally Posted by sosoft

Here is some information about glass annealing from the Corning Museum of Glass reference library:

Annealing Glass

"If a hot glass object is cooled "too quickly," it may be strained at room temperature, and therefore may break easily. For small, or thin-walled shapes (particularly those made of glasses having low expansions) the effect may not be serious. For more massive pieces, the strain can be very serious. The amount of strain (observed in a polariscope) depends upon how quickly the object passes through a critical temperature range. The range depends on the composition of the glass but is usually about 450°C. If the glass is cooled slowly through that range, so that the temperature near the surface is never very different from that of the interior, then the strain in the resulting object is much reduced. . Such glass is said to be Annealed."

The point that sticks out is the second sentence about small or thin walled pieces.

I share this because it says nothing about the amount of time that SLOWLY represents. This is just common knowledge and most hot glass workers test COE and compatibility for each specific project. Just buying a kiln and following a program on the internet doe not mean you are annealing glass. You might have only reduced that chance that it won't crack from thermal shock.
By the way 450 degrees C is 842 degrees F. I have never seen a post on this board that recommends soaking any type of soft glass at that temperature to anneal it.
HITK,
Kurt

And if you had continued reading you would have seen the following on the same page:

"Annealing:

The process of slowly cooling a completed object in an auxiliary part of the glass furnace, or in a separate furnace. This is an integral part of glassmaking because if a hot glass object is allowed to cool too quickly, it will be highly strained by the time it reaches room temperature; indeed, it may break as it cools. Highly strained glasses break easily if subjected to mechanical or thermal shock.>"

[jamie lynne]

well if we didn't scare him off before..... we certainly did now.. lol.

facts of any kind should be cited, true or untrue give credit where it's due (thanks to my english teacher for that little tid bit, see i cited my teacher, i teach by example, lol)

atleast people will know where you got your info, and know that it wasn't just pulled out of your, ahhhhhemmmm, butt. (cleaned that one up for ya! lol)

[AKDesigns]

Originally Posted by sosoft

Ok,
Boiling and bubbling glass is just too hot. Water boils at 212 F. Glass boils at different temperatures depending on the type of glass and it's chemical make up. Boiling any glass is not very good, unless you want to produce a specific effect, like intense black spreading on anice white.
You can try to slant my comment any way you wish. I was only trying to give info about cooling a flame. If I was in error and the OP wanted to know how to reduce a metal based glass, then I apologize. There seemed to be a lot of info in the thread about just working cooler.
JMHO,
HITK,
Kurt

Frida tends to not like oxygen. Just upping the propane a tad stops the glass from bubbling. If you had ever worked with Frida or if you had any then you could see that for yourself....hence the advise Ron and I gave. I'm not quite sure temperature has much to do with it when it comes to this particular glass.

[AKDesigns]

And with that....I'm done. It's just getting silly, silly I tell you!

[jamie lynne]

ohh come back! it is already off it's tracks, might just as well have some fun with it now!

[AKDesigns]

[pam]

If you've never played on the Corning site, here is a link. There is lots of really great info there.
http://www.cmog.org/Default.aspx

[sosoft]

Originally Posted by jamie lynne

well if we didn't scare him off before..... we certainly did now.. lol.

facts of any kind should be cited, true or untrue give credit where it's due (thanks to my english teacher for that little tid bit, see i cited my teacher, i teach by example, lol)

atleast people will know where you got your info, and know that it wasn't just pulled out of your, ahhhhhemmmm, butt. (cleaned that one up for ya! lol)

I think the post had the source as the first line, forgive me as my memory is a tad slow.
Again, the reference said nothing about annealing to a schedule, any ramp, soak, or heat range.
The article describes how glass was cooled in the beginning, by just leaving it on top the clay brick furnace. This is something they do in Israel to this day and they make household glass ware for cooking and drinking. To ramp that information up into Dangerous Cracking Glass Beads is silly.
You all may think you got it going on when it comes to glass bead making, but the fact is that none of us can paint the entire picture of glass history.
Taking the entire bead making thing so seriously is just not helpful to the newcomer IMHO.
There are no absolutes when it comes to any art form. To take the fun out of glass, by reducing the knowledge to such a narrow view is not helping change the minds of people who turn lamp work away from art fairs because they say "it is a craft hobby, this has no place with fine art"
It's our choice, I choose to support glass art.
HITK,
Kurt

[jamie lynne]

this is the post that i was curious about. what's your source? inquiring minds want to know. LOL

Originally Posted by sosoft

In the whole world of lamp working, art glass bead makers that sell their work to the public are no more than 1% of the total.

[sosoft]

Originally Posted by AKDesigns

Frida tends to not like oxygen. Just upping the propane a tad stops the glass from bubbling. If you had ever worked with Frida or if you had any then you could see that for yourself....hence the advise Ron and I gave. I'm not quite sure temperature has much to do with it when it comes to this particular glass.

Ak,
Yes, and just upping the propane a bit from a neutral flame cools it down a bit.
Some of the little I know:
neutral is the hottest flame on a mixed gas torch, adding propane OR oxygen and changing the mix cools the flame.
Adding propane is a reduction flame, adding oxygen is an oxidizing flame, but we already knew that didn't we?
See, I really didn't have an answer either,and I am quite sure of that
HITK,
Kurt

[AKDesigns]

And Frida will still boil if you up the oxygen so you've helped to prove my point. It's not a temperature issue with Frida but a flame chemistry issue.

[likes to make glass stuff]

the only reason I posted about pyrex was so that newer folks wouldn't buy it and hope to melt it as boro...ask me how I know

(bought it, then found out that some of it is soda lime. Thrift shop purchases, but I don't even want to deal with trying to figure out whether it's old enough to be boro or not. )

[jamie lynne]

also as a side note, that post wasn't directed at you personally, it is something i think every one should do... for example, if i got my info from wiki people might know why i was misinformed

[sosoft]

Originally Posted by jamie lynne

this is the post that i was curious about. what's your source? inquiring minds want to know. LOL

Let us see,
There are perhaps 3,000 active glass bead makers in the US.
How many folks attend The Gathering for example?
Ok, lets say that there are 10,000 others who just make beads from soft glass. I give you 15,000 in the US and perhaps 5000 in the rest of the world. 20,000 total.
There are 250,000 folks working in soft glass in China alone.
Add the world wide total of the furnace gals/guys, and students maybe 50,000 more?
Ok, lets get real, the commercial glass industry employs about 400,000 workers in the world. Water glasses, plates, those PYREX dishes, Stuben, window pane, lab glass ware ( oh I forgot the torch working lab boys in industry, 10,000 at least) Can we include the raging rockers of the boro world? 10,000 worldwide.
We gotta give Tommy Chong credit for the time he spent in jail for making glass bongs on a commercial scale,(another 5,000 workers). What about the folks who make our glass? Gaffer, Zimmerman, Lausha, Moretti Etc, gotta be at least 5,000 folks. I think I could find a few more, but you get the picture.
COE, Annealing, compatibility, color mixing, metal laden glass. It has all been done before, slapping glass into a press has been done to make beads for at least 200 years. Selling little presses for $75 to make beads at home, maybe 10 years.
My point again is that none of us know enough to tell anyone some absolute fact about hot glass working. I don't care if you make beads, marbles, or glass eyes (Germans are the best)
There will always be some issues that can not be answered with simple facts. As a science and an art form, glass is one of the most fascinating substances on our planet. I, for one, am now going over to the shop and play around. It always gets my mind off of the little blips, like my time on LE today.
Good luck, have fun
HITK,
Kurt

[jamie lynne]

so it is an educated guess.... not a fact?

[sosoft]

Originally Posted by AKDesigns

And Frida will still boil if you up the oxygen so you've helped to prove my point. It's not a temperature issue with Frida but a flame chemistry issue.

Ak,
I can put Frida or Sam or Clarence(or any of the other cute little hype names for silver glass) into the back of any flame chemistry and it won't even melt, so what is your point exactly?
I have already stated SEVERAL times that I do not use the overly expensive silver glass. I bought FOUR rods last year!
If you are a master at silver glass, I congratulate you. I am not.
My experience is with working soft and hard glass in the torch.
I also fuse it, grind it. polish it, bake it, mix it, make it, and in my experience am fascinated by the art objects I can make with it.
If all of you want to criticize me for that, then I am guilty as charged.
You can't steal my joy as it comes from within myself. I can't control anyone's experience with glass or anything else in life.
Just my experience, hope you find joy with yours!
HITK,
Kurt

[sosoft]

Originally Posted by jamie lynne

so it is an educated guess.... not a fact?

The title of the post speaks for itself, you are welcome to post your idea of our place (beadmakers) in the world of hot glass.
HITK,
Kurt

[AKDesigns]

Originally Posted by sosoft

Ak,

I have already stated SEVERAL times that I do not use the overly expensive silver glass. I bought FOUR rods last year!

Then why oh why did you give a noob advice (bad advice) about a silver glass when you are admitting you have no experience with it? Priceless!

[sosoft]

Originally Posted by sosoft

The title of the post speaks for itself, you are welcome to post your idea of our place (beadmakers) in the world of hot glass.
HITK,
Kurt

Ps.
Not to put too fine a point on this drama today, but the original thread about encasing siver glass where I opened this can of frit has an interesting ending.
It seems that Abe only got a hand full of requests to replace the "BAD" DC glass he makes for a living. I think I remember him stating that out of 1000 batches he only had 3 that were not the correct COE.
I saw 6 or 7 people try to convince the entire LE board that only the DC could have been bad, not one of them even pondered that techinque, or kiln heat, or thermal shock MIGHT have been the problem.
Those folks are all happy now that they got brand new glass from what I see as thin (or should I say hot) air.
They ignored facts stated by the manfacturer and others, (I wasn't the only one defending the DC clear)
I hope they are happy with the new glass.
HITK,
Kurt

[BeadMaven]

Originally Posted by sosoft

Ak,
I can put Frida or Sam or Clarence(or any of the other cute little hype names for silver glass) into the back of any flame chemistry and it won't even melt, so what is your point exactly?
I have already stated SEVERAL times that I do not use the overly expensive silver glass. I bought FOUR rods last year!
If you are a master at silver glass, I congratulate you. I am not.
My experience is with working soft and hard glass in the torch.

So why would you even post to answer questions regarding a glass you haven't even used? The question about flame chemistry would be directly involved with the glass being used - in that case Frida.

Silver glass is soft yes, but its not the same as a regular, non silver glass.

Eh, didn't Abe come in and after testing, and say there was in fact a problem with a specific batch of DC? I thought he did.

I disagree with your opinion on annealing as well but I'll let Pam and others handle that. lol

[sosoft]

Originally Posted by AKDesigns

Then why oh why did you give a noob advice (bad advice) about a silver glass when you are admitting you have no experience with it? Priceless!

Ak,
I see that you know it all, so I will humble myself before you.
Thanks for the critique,
I will try to do better in the future,
HITK,
Kurt

[AKDesigns]

Originally Posted by sosoft

Ak,
I see that you know it all, so I will humble myself before you.
Thanks for the critique,
I will try to do better in the future,
HITK,
Kurt

word.

[jamie lynne]

[sosoft]

Originally Posted by BeadMaven

So why would you even post to answer questions regarding a glass you haven't even used? The question about flame chemistry would be directly involved with the glass being used - in that case Frida.

Silver glass is soft yes, but its not the same as a regular, non silver glass.

Basic torch working will not be revolutionized by melting silver 104 COE glass, sorry.
HITK,
Kurt
Ps. If anyone actually reads what I post, then they would know that I have some experience with melting metal and glass rods in a mixed gas torch. I was mixing glass with silver in the torch before LE was a chat board. I just don't buy into the expensive silver glass sold now days.

[pam]

Approximately 5 years ago there were around 35,000 ART glass workers in the US. I don't have a clue what it is today, more or less. This does not take into account factory workers.

[AKDesigns]

Originally Posted by sosoft

Basic torch working will not be revolutionized by melting silver 104 COE glass, sorry.
HITK,
Kurt
Ps. If anyone actually reads what I post, then they would know that I have some experience with melting metal and glass rods in a mixed gas torch. I was mixing glass with silver in the torch before LE was a chat board. I just don't buy into the expensive silver glass sold now days.

Actually silver glass is a completely different animal. And if you don't "buy into" the expensive silver glass then don't buy it, don't trash it and don't give people advice on how to use it.

[BeadMaven]

Originally Posted by sosoft

Basic torch working will not be revolutionized by melting silver 104 COE glass, sorry.
HITK,
Kurt
Ps. If anyone actually reads what I post, then they would know that I have some experience with melting metal and glass rods in a mixed gas torch. I was mixing glass with silver in the torch before LE was a chat board. I just don't buy into the expensive silver glass sold now days.

Using silver glass is completely different than mixing silver with glass.
Its clear you haven't any experience in working with the expensive silver glasses.

[BeadMaven]

Originally Posted by AKDesigns

Actually silver glass is a completely different animal. And if you don't "buy into" the expensive silver glass then don't buy it, don't trash it and don't give people advice on how to use it.

GMTA!

[jamie lynne]

well, as Lorraine said in response to me earlier, some threads derail and it is funny and some are serious.... since this one went from derailed to a train wreck, can we turn it into a funny one? please ohhh please! i'll start!

amy if you will do the happy dance with me, i will also be humbled before your greatness too

[pam]

Originally Posted by sosoft

Ps.
Not to put too fine a point on this drama today, but the original thread about encasing siver glass where I opened this can of frit has an interesting ending.
It seems that Abe only got a hand full of requests to replace the "BAD" DC glass he makes for a living. I think I remember him stating that out of 1000 batches he only had 3 that were not the correct COE.
I saw 6 or 7 people try to convince the entire LE board that only the DC could have been bad, not one of them even pondered that techinque, or kiln heat, or thermal shock MIGHT have been the problem.
Those folks are all happy now that they got brand new glass from what I see as thin (or should I say hot) air.
They ignored facts stated by the manfacturer and others, (I wasn't the only one defending the DC clear)
I hope they are happy with the new glass.
HITK,
Kurt

Kurt, what are you trying to do here, rewrite history according to Kurt? Many different people using different annealing schedules and different combinations of glass and different techniques, who had previously had success when using DC, all of a sudden were experiencing cracks when using a specific batch of DC glass. Using the same color combinations and annealing schedules and techniques there was no breakage when using another clear. And Abe tested and as a result of his testing replaced the glass for anyone who chose to have it replaced. You are writing fiction.