cullet shortage

[Sky Campbell]

He might really enjoy Lichtenberg effects on wood with a high frequency welder or using a magnetron from an old microwave. Lots of info on the web. I got lost in it for hours. A little borax and water on the wood wipe until it's just damp and zap instant gratification.

[Greg Vriethoff]

Originally Posted by Eben Horton

how about piercing a semi molten 6" sphere with the 30/30 ?? put a pipe hanger outside by your horse trailer and tie a string to the trigger......



what could possibly go wrong?!?!?!

Reminds me of the "bullet in amber" letter from Glassnotes 4.

[Eben Horton]

What was that greg?

[Greg Vriethoff]

It's in the section near the end where Henry reprinted some of his funniest "Ask Dr. Glass" letters. Apparently, someone wrote to Henry asking if it would be feasible to fire a round into a gather of hot glass. They wanted to know if the glass would actually shatter from the impact, or if it would lodge itself in the gob like it was "embedded in amber", or somesuch.

I haven't unpacked my copy since moving my studio, so I don't know exactly what they said, but it went into all manner of pseudo-scientific descriptions of what might happen.

[Eben Horton]

hA! That is exactly what i was getting at.

[Mark Rosenbaum]

Originally Posted by Greg Vriethoff

It's in the section near the end where Henry reprinted some of his funniest "Ask Dr. Glass" letters. Apparently, someone wrote to Henry asking if it would be feasible to fire a round into a gather of hot glass. They wanted to know if the glass would actually shatter from the impact, or if it would lodge itself in the gob like it was "embedded in amber", or somesuch.

I haven't unpacked my copy since moving my studio, so I don't know exactly what they said, but it went into all manner of pseudo-scientific descriptions of what might happen.

I think that it was done at a certain school in N.O. before I got down here. It depended on the temp and thickness of the glass....

[Lawrence Duckworth]

Originally Posted by Sky Campbell

He might really enjoy Lichtenberg effects on wood with a high frequency welder or using a magnetron from an old microwave. Lots of info on the web. I got lost in it for hours. A little borax and water on the wood wipe until it's just damp and zap instant gratification.

I wired a red light into the line to warn myself not to touch anything while its burning..

I also did a couple of turkey calls that turned out pretty cool...lots of fun!

[Pete VanderLaan]

Originally Posted by Sky Campbell

He might really enjoy Lichtenberg effects on wood with a high frequency welder or using a magnetron from an old microwave. Lots of info on the web. I got lost in it for hours. A little borax and water on the wood wipe until it's just damp and zap instant gratification.

******
We did that last week. Nice!

[Durk Valkema]

3 years that is very short, recuperated so gas fired I presume.
The borax sure dos not help but what you are seeing is Nephelin formation.
The moment melting temperatures dropped with the low melting batch we saw this phenomena, before only seen in flue area's at the right temperature. We used to race up to 1300+ C charge and melt at 1340 to 1360 C (2380 F charge, melt at 2450-2480F) Now charging 1240 C lingering at 1270 C or 2320 F the calcium in the castibles with the AlumoOxide react with the Alkaline, all of them forming Neph that has a differend expantion so it forms nasty flakes.
They used a very bad castible on that furnace, things are a bit better with the low cement materials but this issue is persistent.
Really 3 years is crazy. We have a client melting 26 metric tonne a year in one single (had a premature one only once) Magma crucible holding 500lbs GLASMA batch, melting 4 times a week. We set the furnace in 2008, you see the Neph formation and we changed the gathering plate 3 years ago, it has another 10 years in it.

[Pete VanderLaan]

we've got a language issue Durk/ We should talk. The general take is that melting boron using refractories in this country for smaller furnaces have issues on units with no flues. Borax has been considered a go to material here since 1980. It has consequences. Americans want glass from toothpaste tubes.

[Jordan Kube]

I don't see a similar thing happening to Wetdog furnaces using the other glasses. It's hard to point to their choice of refractories in this case. That glass was brutal to non contact furnace structures.

[Pete VanderLaan]

Lets clarify a bit here.

Durk is talking about batched glasses in a gas unit I believe. Nephelin is a type of feldspar which has a basic structure of soda/potash/ alumino silicates. Durk implies that it forms but is not introduced into a melt. My interpretation of that is that in the flue, there is a phenomenon of devit flakes occurring when the temps are just right, somewhat on the colder side.

Calcium aluminate is used as the cement in castables which hasten the setting of the castable but reduce it's resistance to attack at the same time.

Jordan, I believe is not talking about gas units at all but is referring to cullet melting. The glass he refers to was the system 96 made by spectrum in conjunction with now departed Uroboros which indeed was a low temperature mel cullet that chowed down ( a technical term) on silicates, aluminates and fireclays in a variety of furnaces but was really worst in electric units with no flues. The liner photo he shows is I believe, a wet dog cast portion that dissolved using the system 96. Jordan appears to say he is not seeing the same kind of dissolution with the Cristalica but needs more time to watch it.

Both of these glasses currently are under scrutiny because of their Boron content. Boron with barium around 3% would in my mind add to the issue. I am getting feedback from some kiln makers that the Cristalica is having detrimental effects on their products in a short time. That is using alumina crucibles from either High Temp or Engineered Ceramics. The crucibles do not appear to be affected and I would have expected that they would be.
It seems to me that the jury remains out on the affect the German cullet will have on the American furnaces. Simply put, European furnaces in general use higher quality refractories.
The GLASMA claims Durk makes in the Gas units is not something I can really compare anything to. First, I don't know what GLASMA Batch it is and secondly, it certainly sounds like a very different furnace structure as well as being gas fired, not electric. It remains to be seen whether Cristalica gets the boron out of the goop. I certainly advocated for that when Tom Littleton and I first brought the stuff into the country two years back but as I have noted, they declined changing anything. I am no longer affiliated with that arrangement in any way. I do sell pots.

I hope that sums up what I can see would be fairly confusing. Is that the case, and am I accurate?

[Jordan Kube]

My pictures are above glass line pictures. I didn't necessarily see it eat into the AZS refractories. The tank itself holds up reasonably well. Wet dog makes awesome furnaces.

[Pete VanderLaan]

Thank you for the clarification. Nasty Stuff. I agree Eddie makes nice tooling. Pricey.

I modified my prior post to support the clarification.