working temp for bullseye coe 90

[Joe Hooper]

/ have found myself working with some bullseye coe 90. It seems awful thick to me. it is being kept at around 2070 +-.
Maybe the pot is not big enough to keep it hot 20-30lb. The question is....what is a good working temp for this stuff? when a gather is done it looks like warm soft ice cream. stringers ect....



thnx,




Now in Beautiful New Mexico

[Jon Myers]

Just turn it up until you get what you like.

[Joe Hooper]

its not my pot. I was just using someone else's. What I am saying is its not my place to change temp. I just think its really cold.

[Edward Dluzen]

This might help

Working Temperature (http://www.bullseyeglass.com/viscosity/tech.html)

From Bullseye website.

e
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[Brice Turnbull]

Your info isn't really detailed enough for a comprehensize (read:short & helpful) answer, but from what I think you're saying & asking I'll just mention there are a few possible things happening.

1) working temp of a furnace is basically to taste. There is no right or wrong, only what the operator prefers. Maybe they have a personal reason to keep the glass in their furnace the way it is.

2) "glass" in molten form is a steadily changing material. It is not the same from one day to the next, although to the human observer the change isn't usually notable until 4 or even 6 days have passed.

If the glass you were gathering has been molten for 7 or more days, then you're probably just working with old, short glass.

P.S. since Bullseye's website says their glass is a short glass, it could be stringy and short (tough) right from the get-go. I haven't the experience with that particular glass body to say.

3) Possibly the studio you're working from used two different lot #'s or types or varieties of cullet in the furnace without completely cleaning out the old before adding the new. Or, they just melted on top of a bit of the same type of old glass as new glass, but the old has been molten a while longer, and when they mixed during deeper gathers, the older glass lent chords, etc. to the rest of the crucible.

4) If a glass is melted at a higher temp or a longer time at high temp (during initial melt, or when re-melting cullet), it will be short (tough) from the first day after melting.

However;
since you don't have control over the furnace or studio in question, what is it you want us to tell you to do?

Good luck in whichever way you go,
Brice

[Brice Turnbull]

Oh yeah, and the 2070 work temp is unfortunately not the only clue needed to know what's going on in that furnace.

At what height up and down, and depth in & out is the thermocouple in the furnace?

Your elevation will change the condition of the glass at the 'same temperature' as a much different elevation (I work at 7000 feet in Colorado now, but in Kansas at 2500 feet, I did most things including annealing at almost 40 degrees colder to achieve the same result).

It will really just take trials in that furnace with that glass to get it the way you like it to be.

[Kenny Pieper]

I'm curious how do you think that the altitude could change the viscosity or annealing point of glass?

[Pete VanderLaan]

Altitude doesn't change anything here. I would point out that a 90 L.E.C. glass is going to be short in working time by it's very nature. I certainly don't think that bullseye is the glass of choice for a blowing material. I know they have introduced what they call a blowing glass but my opinion remains that there are better sources.

[Joe Hooper]

Thanks all for trying to answer half a question. I understand What you are all saying.



Thanks again

Is there no "actual" hot shop in Albuquerque?

[Brice Turnbull]

Hi Kenny,
well, it was just my guess that the change in temperatures required was caused by the change in altitude.

I brought the furnace and annealers with me, and the result is that I need to set my temps 40 degrees higher to get the same result in both the furnace and annealers, with the same controllers, furnace, annealers, thermocouples, and thermocouple insert holes as compared to my temps & glass in Kansas.

Could be something else happening, but I don't know what.
Cheers, Brice

[Rosanna Gusler]

gas? less O2 to burn with? rosanna

[Brice Turnbull]

Hi Rosanna,
I all electric actually.
Furnace & annealers.

Only other difference I can think of is humidity, but on rainy days it's not different than dry days.

Who knows?

tnx, Brice

[Cynthia England]

Joe..
Way Way a looooooooooong looooooooong time ago..
(sorta like 'once upon a time')
I worked with BE in a furnace... Nasty stuff!! absoultly NO
working life.. stiff and 'snotty' at the same time.. it will really not
help to turn it up .. as soon as yu gather and head for the bench
it will be stiff as bottle glass (which is what is mimice!! )
yu can move the bench closer to the furnace and GH and you can get a few more seconds..
This is where yu learn to work fast!!!!!!!!!!
bet ya they really did not reformulate it too much..
but if you Flux it 'a bit' it may help.. it is just basic soda lime glass
really basic.. I have the original formula someplace in my notes..
maybe Lannie can answer yu better if she is lurking?

Marver Tart

[Pete VanderLaan]

Originally posted by Cynthia England
Joe..
it is just basic soda lime glass
really basic..
Marver Tart
********************************
With a lot of lime comparatively which makes it runny and short lived all at once. If you add soda, it just dulls it up while giving only a marginal increase in working range.

[Franklin Sankar]

Ok I am in the middle of an elections here but cant resist this one.
Joe Hooper, what did you try to make with it and how hard was it to work. SOunds like near to bottle glass? Can you make a horse with it.
Franklin

[Scott Novota]

Franky you crack me up.

You are to bottle glass like Ben is to Bisket.

Keep on truck'n my friend. Hope you are well.


Scott.
.

[Dave Bross]

A bit of borax would help things along with minimal expansion change but that's probably not do-able if it's not your melter.
If you could do it, shoot for something in the 1 to 1.5 percent boron range for starters and increase from there for more working time, remembering that borax is about half soda, half boron. It would make the glass look better and work longer.

I know, this is "bad dog!" behavior, but I'm a great fan of sometimes being better to beg forgiveness than ask permission. So much for encouraging responsible adulthood.

I don't think any of us can ever think of bottle glass again without having Franklin in the same thought?

I can't even imagine what an election in Trinidad might be like. Probably make us Floridians look good. I would hide too.

[Brian Blanthorn]

Originally posted by Brian Blanthorn
There R some weird colours with BE that either change or get incompatabble on heating above 1600

Marty got a mail from BE specificaly about a over heated yellow which became incompatable

Go over warm glass I told him 2 post it there

Having said that most BE colours appear ok hot + soaked

Some BE coulours will give a 3 rd colour at the interface

In the letter they said that BE was compatibility tested well bellow 1600 which 2 my mind is not that hot

Some of the colours may not like flaming n long heating

Some BE coulours will give a 3 rd colour at the interface

I think threre was a list over warm glass

Warmglass is in repair at moment should b back soon

Brian

[Pete VanderLaan]

Anytime you heat a cadmium or selenium based glass up hotter than 1600F, it's going to walk and talk.