Too Extreme?

[CD Lampwork]

I think the bottom line is this is a simple test anyone can preform. Most of the variables have been removed (boiling water and ice water are set temperatures). I would argue that it is a relatively decent indicator of sufficient annealing and compatibility. It is absolutely not the end all be all of testing, but it does seem to conform to Corning's tests at least. And it would appear to not damage the bead. At least if the bead started out okay in the first place. The drop test is a nice finishing test to ensure any slight abuse can be tolerated. I don't really think 4" is much of a test, but I'm not arguing that one too.

And at the end of the day, Mike's question dealt with is this test too extreme. Again, I don't think so. But sure, a really well thought out thorough testing procedure would be helpful. I don't think anyone would use it though.

[jaci]

Originally Posted by Mountain Snail

I fire mine from a cannon at castle walls!

Well close... I polish my key beads on a buffer wheel and sometimes they get sucked in and launched at about 60mph into a stone and concrete wall. Almost every one that this has happened to has survived! The ones that didn't were either a weird pertruding shape/design or something like that. Didn't ever try it with a bead not on a key though..

[CD Lampwork]

Originally Posted by Elizabeth Beads

Would you open you kiln when it reached 212 and take out your beads? I wouldn't (let alone plunge them immediately into cold water). And if I did and they cracked I would consider it thermal shock and not inherent stress in the glass.

Fair enough. I'll take on the math. Using the Corning chart I listed a couple of posts back:
a 150mmX150mmX3.2mm annealed soft glass blank is expected to survive a 65 degree thermal shock.
150X150X6.4 50 degrees
150X150X12.7 35 degrees

Translated to something I can use:
285,750 mm squared of glass 35 degree change
144,000 50 degrees
72,000 65 degrees

So basically each time the amount of glass was cut in half the degree change went up by 15 degrees C

Mike's original question dealt with a 12mm bead. Assuming it was a square bead that would be 1,728 mm squared of glass. By the time you half the above figures enough to get down to 2,250 mm squared the dramatic temperature drop to induce thermal cracking would be 140 degrees C. That works out to a temperature change of 284 F.

I'm not saying my above figures are correct for the way glass actually behaves. I'm making some pretty big assumptions. And the Corning tests involved big (relatively) flat sheets of glass vs. our nice round beads. But there is at least an indication that a small bead should be able to survive a drastic temperature swing of 284 F. And having tested larger beads with the boil-ice method I'm confident a 180 degree F swing should be survivable.

[Kalera]

I think it's absurd and unscientific, and polarized lenses are not all that hard to come up with, especially for someone who is making 1000 beads. Any pair of 3-D movie theater glasses contains two plastic polarized lenses.

Boiling-to-ice-water is a silly test that makes the industry look childishly foolish, IMO.

[Kalera]

Anybody here a fan of iced tea? Seen what happens when you put a bunch of ice in a drinking glass, and then pour freshly-brewed hot tea in on top? It might not happen every time, but if you do it a few times eventually that glass is going to break.

There are good reasons we don't put our valuable blown art glass pieces in the dishwasher or the microwave, and that's less of an extreme. Even so, I have pulled glassware out of the dishwasher that couldn't take the heat and broke during the cycle.

Sure, small round beads will survive this "test". But do we as beadmakers really want our clientele to start thinking this is some sort of a legitimate test of glass quality? I'm not going to boil and dump in ice water one of my $125 30+ layer 2-inch lentil focals, or a sculptural bead, or a vessel.

Glass fatigues over time, accumulating stresses, and may eventually break from those stresses. I don't want to start my beads off by adding a level of stress that they would never normally see over a lifetime.

[CD Lampwork]

Originally Posted by Kalera

I think it's absurd and unscientific, and polarized lenses are not all that hard to come up with, especially for someone who is making 1000 beads. Any pair of 3-D movie theater glasses contains two plastic polarized lenses.

Boiling-to-ice-water is a silly test that makes the industry look childishly foolish, IMO.

*Heavy sigh* Well I don't think discussing quality testing in an open, honest, thought out way makes our industry look either childish or foolish. Quite the opposite in fact. And as Corning lists very similar tests I'd argue in favor of the scientific validity and legitimacy of such testing.

Polarized lenses are an excellent form of testing. However:
1 beads with plunged CZs
2 104 COE with 94 COE raku decorations (either surface or encased)
3 copper foil encased
4 Silver encased
All have the strong potential for showing stress under a polariscope. So, how much stress is acceptable and how do you test the stress level in a practical way? No, I'm being serious. I'm not married to this boil-ice test. But show me the science to disprove it. Show me a manufacturer or science paper or something other than personal observation to indicate it does damage to the bead. Because so far, all my research is showing me it does no harm.

I'm also not finding any support for the idea that glass fatigues over time due to thermal variations. Unless that temperature extreme reaches the strain point of course. In fact quite the opposite. Both Corning and Arrow Springs claim that, once annealed, glass won't take on any permeant new thermal stress. Corning even lists the normal usable upper temperature for soft glass as being 230 degrees F.

I'm really not trying to be difficult here. All I'm asking is show me where I'm wrong and propose a reasonable alternate test. Just make sure that test also includes how to deal with techniques that may well induce a certain amount of stress. Because it's not always just our techniques. There are a number of 104 glass colors that I don't use because I've found them to not play well with others in my big marbles. Actually it's that lack of quality testing that drove me to using bullseye. Their glass is really nicely tested.

[Baywinger]

My question is has anyone tried this with un anealed beads?
does this test actually prove anything? if it does great but if un anealed beads can surive it as well then it proves nothing.
Just want to point out if you want to make/use a test to prove something make sure that it is a valid test
also make sure you use a large sample of each anealed and un anealed beads to make sure you get the results you are looking for

[Kalera]

The problem is not the upper temperature, it's the rapid 200-degree change. You can boil glass all day long and it won't hurt anything if you pull it out and let it cool to room temperature. It's a bit different when you deliberately shock it by plunging it into ice water.

Information on thermal fatigue:

http://www.newton.dep.anl.gov/askasc...9/eng99265.htm

Most of these require a subscription but there is a little info in the abstract:

https://springerlink3.metapress.com/...ringerlink.com

http://www.sciencedirect.com/science...6784429190038L

http://www.osti.gov/energycitations/...sti_id=6654125

http://onlinelibrary.wiley.com/doi/1...556.x/abstract

Next time I'm at school I'll try to remember to pull the full text if I have time.

[Mountain Snail]

Originally Posted by jaci

Well close... I polish my key beads on a buffer wheel and sometimes they get sucked in and launched at about 60mph into a stone and concrete wall. Almost every one that this has happened to has survived! The ones that didn't were either a weird pertruding shape/design or something like that. Didn't ever try it with a bead not on a key though..

I have flung beads with my little electric bead reamer. Next time I feel a castle invasion I will have to try the key trick for self defense.

[CD Lampwork]

Well Kalera, I'll grant you those are much more interesting articles than the experiential evidence given so far.

From what I'm reading the first link talks about repeated heating and cooling (cookware) over the course of years and at a much more elevated temperature difference. We're talking about one relatively mild (relative to a pot being put on a stove top) temp swing evenly distributed over a small amount of glass. They're talking about a much more intense stress being repeated thousands of times. And even then their speculation involves the temperature difference from the relatively hot section of glass vs. the cooler sections as the cause of the fatigue. Our little test bead is being heated and cooled rapidly, but due to the amount of glass relatively uniformly.

The other articles are a little harder to get a handle on as they're just abstracts. But there does seem to be some studies indicating thermal fatigue in glass is possible.

My questions would be:
1. what sized glass were they testing? From the Corning info the larger the piece of glass the lower the temperature difference to induce thermal shock. I would assume the same would hold true for thermal fatigue.
2. What was the temp difference used to create the fatigue?
3. Was there a temperature difference that was considered safe?
4. How many repetitions of the test were required to result in measurable stress?

If a polariscope test on an annealed bead shows no stress. Then the bead is subject to the boil-ice test. Then a follow up polariscope test indicates no stress, I would propose that the test did no measurable harm. From what I'm reading in these abstracts the authors are talking about extremely small cracks which the glass is able to handle due to its structure. It's only when a crack grows to above some particular measurement that the glass exhibits fatigue. And some of these articles seem to be more about industrial applications. A more intense environment for the glass than what we're dealing with.

If the answer is no amount of temperature quenching is acceptable and any test of this sort creates damage. Well, I suppose we'll have to agree to disagree. So far I haven't seen anything to convince me one test conducted within the Corning operational limits of soft glass creates damage. And though repeating a much more aggressive test thousands of times might create fatigue, there's also speculation that the fault may have been in fabrication or use.

[Kevan]

Why do people assume China made beads are not properly annealed? They have kilns over there.

[Kalera]

Originally Posted by CD Lampwork

Well Kalera, I'll grant you those are much more interesting articles than the experiential evidence given so far.

From what I'm reading the first link talks about repeated heating and cooling (cookware) over the course of years and at a much more elevated temperature difference. We're talking about one relatively mild (relative to a pot being put on a stove top) temp swing evenly distributed over a small amount of glass. They're talking about a much more intense stress being repeated thousands of times. And even then their speculation involves the temperature difference from the relatively hot section of glass vs. the cooler sections as the cause of the fatigue. Our little test bead is being heated and cooled rapidly, but due to the amount of glass relatively uniformly.

The other articles are a little harder to get a handle on as they're just abstracts. But there does seem to be some studies indicating thermal fatigue in glass is possible.

My questions would be:
1. what sized glass were they testing? From the Corning info the larger the piece of glass the lower the temperature difference to induce thermal shock. I would assume the same would hold true for thermal fatigue.
2. What was the temp difference used to create the fatigue?
3. Was there a temperature difference that was considered safe?
4. How many repetitions of the test were required to result in measurable stress?

If a polariscope test on an annealed bead shows no stress. Then the bead is subject to the boil-ice test. Then a follow up polariscope test indicates no stress, I would propose that the test did no measurable harm. From what I'm reading in these abstracts the authors are talking about extremely small cracks which the glass is able to handle due to its structure. It's only when a crack grows to above some particular measurement that the glass exhibits fatigue. And some of these articles seem to be more about industrial applications. A more intense environment for the glass than what we're dealing with.

If the answer is no amount of temperature quenching is acceptable and any test of this sort creates damage. Well, I suppose we'll have to agree to disagree. So far I haven't seen anything to convince me one test conducted within the Corning operational limits of soft glass creates damage. And though repeating a much more aggressive test thousands of times might create fatigue, there's also speculation that the fault may have been in fabrication or use.

Ok, but my point is that as a "test", it's silly. It's meaningless. Meaningless tests just make us look unprofessional.

[Kalera]

Originally Posted by Kevan

Why do people assume China made beads are not properly annealed? They have kilns over there.

In my experience, many of them aren't. I'm sure that some are, but unless they specifically say that they are I would assume they aren't.

I have bought Chinese beads only to see over half of them crack. I did make myself a lovely bracelet from the ones that didn't crack.

In the case of un-annealed beads, freezer to warm water or vise versa is usually enough to find out whether they were annealed; un-annealed beads will usually crack under those circumstances.

If you already know that beads are annealed, the freezer test is unnecessary. If you doubt your supplier's word, then it's worth a go.

[Lisi]

Originally Posted by Kevan

Why do people assume China made beads are not properly annealed? They have kilns over there.

A long time ago when I was a big spender on ebay, I bought a lot of Chinese lampwork. $5.99 strands of 12 beads direct from China. Beautfully made, I thought. Bubble dots, and encased layered petal florals. I could find some pictures of the types online to show you what I bought. I never made them into jewelry, and stored them away for about four years. When I dragged them back out again to use them, 11 of the 72 beads were broken. Clean in half, thermal shock break.

11 broken out of 72 = not annealed.

[Rudy]

I found this thread very interesting because shortly after I started making beads that were good enough to sell, I approached a VERY RESPECTED lampwork artist for her opinion on this very same topic. She told me that the only way I could really know if my beads were well made was to place them in my freezer overnight and then throw them directly in boiling water. If the beads survived, I could consider myself successful. I trusted her opinion and actually made that a part of my bead making process....I succeeded (about 95% of the time), and felt good about it because I trusted this person. I later realized that this was ridiculous, and I wonder if she was setting me up for failure and not being as supportive as I thought....just sayinnnnnn. Three years later, I think such extremes are silly.

[Sheila D.]

I think Mikey just likes to stir the pot!

[PerfectDeb]

i think its ficticious anyway, i do not believe some major jewellery company demanded that the beads be tested that way - thats just illogical

this is ma beads i'm talking about - i have no idea what mike is referring to

[Kalera]

Originally Posted by PerfectDeb

i think its ficticious anyway, i do not believe some major jewellery company demanded that the beads be tested that way - thats just illogical

this is ma beads i'm talking about - i have no idea what mike is referring to

Or, it's a company which saw the claims on that website about boiling/freezing beads and bought into it.

The funny thing about it is that if you think you have un-annealed beads it's a quick way to check... but if you think your supplier is lying about annealing, you would want to do such a test for yourself, and not take their word that they shock-tested their beads.

In my opinion, this is another case where educating the buyer would do a world of good. Maybe they should be directed to the ISGB for factual information on annealing and glass durability.

[andreajane]

Originally Posted by Kalera

I have bought Chinese beads only to see over half of them crack. I did make myself a lovely bracelet from the ones that didn't crack.

I've seen strands of mass-produced lampwork on tables at shows, and every strand I picked up had bead release still inside AND every strand had at least one bead that was visibly cracked.

But, when someone can buy a 12-inch strand of lampwork for $6-$10, I guess it's fine to toss the ones that are flawed, same as with strands of inexpensive gemstones and pearls. Most consumers in this country hate buying new things that need to be cleaned before they are used, though. Maybe under-educated buyers don't realize the beige powder in the bead hole shouldn't be there.


Andrea

[glaslight]

I would be suspicious that this someone wants you to waste your time. Definitely require payment in full before you fill their order!

[Lisi]

Originally Posted by glaslight

I would be suspicious that this someone wants you to waste your time. Definitely require payment in full before you fill their order!

Who the hell would want to take an order for 10,000 beads anyway?? Only a mass producing company could handle that. Unless they are giving you a year or two to make them.

[CD Lampwork]

Originally Posted by Lisi

Who the hell would want to take an order for 10,000 beads anyway?? Only a mass producing company could handle that. Unless they are giving you a year or two to make them.

I've seen this question raised before in this thread. As a professional full-time lampworking couple, I'm gonna say we'd consider it. Seriously.

Doing a rough count of how many beads we currently have on our mock up display table it looks like we bring at least 1,500 beads to each show. Deanna's currently doing about 6 shows per year. And the internet still accounts for most of our business. Shows are expensive and hit or miss regarding sales. On line sales are up, down, side to side, often even doing the hockey-pockey.

So a potential order that could keep us fat and happy for a year? You bet we'd consider it. For a big name supply house? Hum, YES! Who demands quality control testing? At 10,000 beads I'd be doing some form of testing just for my own mental well being.

Wouldn't it be boring? Well maybe. But everyone here is making an awful lot of assumptions. It'd be just as easy to assume that this order was meant to end up being a long term association. I mean sure, a company would want to ensure we could make that many beads. Most of our repeat customers are just that, repeat, because they know we've been in business for years and will be able to reproduce the same beads next year. But that mythical company probably doesn't want all 10,000 at once. They may not even want all 10,000 to be the same design. Again there are an awful lot of assumptions flying around.

So, Mike, if you're looking for a couple of established bead makers to hook up for a long term, profitable, perhaps even prestigious commission drop me a line.

Now of course there's going to be a conversation regarding design, cost, timing, even refining the original quality control question. But to just flat out say "no that's stupid go to China. Oh and China will never be able to fill your quality control issue. So I guess you're just screwed?" Sorry, that's what makes us sound silly and unprofessional.

[SuzyQ]

Originally Posted by Lisi

Who the hell would want to take an order for 10,000 beads anyway?? Only a mass producing company could handle that. Unless they are giving you a year or two to make them.

Me. I calculated the number of beads I made over the course of a year for one jewelry designer and it was in the thousands. It was a great gig. I would do it again in a heartbeat.

[CD Lampwork]

Hey back off Susan, this is our order! LOL!!!! Actually we were just looking at our table talking about how you bring way more to a show than Deanna. I suppose we could share. Love ya.

[rosemarie23]

Originally Posted by Lisi

Who the hell would want to take an order for 10,000 beads anyway?? Only a mass producing company could handle that. Unless they are giving you a year or two to make them.

Me! lol!

(no - it's not my order either...)

If you made 200 a day - that would be less than 2 months of time. I'm assuming that they aren't the $125 30+ layer 2-inch lentil focals Kalera mentioned earlier. For an order like that, I'd be burning some midnight oil, uh.... propane.

[Silberrucken]

Originally Posted by mikefrantz

What would you do if somebody wanted you to make 10,000 beads...

?? Tell them to buy 100,000 beads from China and hope to find 10,000 good ones???

Or quote $100 PER BEAD....

[Kalera]

Originally Posted by Lisi

Who the hell would want to take an order for 10,000 beads anyway?? Only a mass producing company could handle that. Unless they are giving you a year or two to make them.

I'd seriously consider it, depending on the timeline and price. When you consider how much less time you'd spend on photography, listings, packaging for shipping, etc. it's very doable in under a year, for small relatively simple beads. When I was torching full time I made over 15,000 beads per year.

[SuzyQ]

Originally Posted by CD Lampwork

Hey back off Susan, this is our order! LOL!!!! Actually we were just looking at our table talking about how you bring way more to a show than Deanna. I suppose we could share. Love ya.

I claimed it last night, lol. But you know I would share

[SuzyQ]

Originally Posted by SuzyQ

Dude, I want that order. I'll test them if that's what it takes.

[ChaseDesigns]

Ah yes, you're right. I guess I'll just have to settle for cleaning beads, dipping mandrels and running the infamous test then.
Ops, sorry, this is Deanna's account. This is Greg obviously LOL