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I've taken a class on Pate de Verre and have been thinking about it for several years. Finally I found some play time and made a small piece (nothing great just proof of concept.. but pic is on photo board). I don't really like the opaqueness of it as I prefer transparent glass. I do some other kiln casting but use cullet to get the best transparency..... This got me thinking.... always trouble...

I own a few Daum pate de verre pieces (very small pieces) and they are very transparent and all one color.... so the real question is... ARE they still pate de verre?

~Nan

I met one of Daums artists/craftsmen many years ago when we were just starting out learning the technique. I asked him how they do their glass. He told me they use one piece molds casting upside down and then pour the frit in dry. He showed me a sample of the frit they use and it was comparable to Bullseye frit size 2 or maybe larger but not as large as BE frit size 3. They call the work pate de verre, but since they don't make a paste of their frit, it is really just frit casting. After all, pate de verre translated means 'paste of glass'. No paste, no pate de verre.

Ellen

Interesting. I can't believe frit size 2 gives the clarity they have in their pieces ..... I would think they would be much more opaque with #2.. I'll have to try one with that size and compare the transparency....

Don't get me wrong; I love their pieces... just wondering...

~Nan

does the firing schedule have anything to do with the clarity of these pieces,,,i was under the impression that frit that small would be more opaque, thanks,,rodney

I have met two definitions of Pate de Verre.
Some say that it is the _paste_ that counts, ie placing wet powder into the mold.

The other school claims that PdV is anything made of so
fine frit that the microscopic bubbles render it opaque.

Frit wafer is another related technique. From the ready product one may not see the difference, but again if it is made dry, I want to call it something else.

PdV is not my stuff but I prefer the firstdefinition, to honor the diligence of those who make it. Frit casting of fine material is so much faster process, that it makes no justice to those who lay it by hand. Using the term too broadly inflayes the terms and the prices erode until the hand laying masters are gone. I do not want that.

The clarity of the glass is a function of temp and particle size.
Increase in either gives a more clear result.

-lauri

The clarity of the glass is a function of temp and particle size.
Increase in either gives a more clear result.

-lauri

thanks for the info,,,,could you suggest a firing schedule, including, the anneal for the small particles that were mentioned, as the size used by daum,,,,,,,,,,,thanks, rodney

hi there ellen,,,,,thanks for that info on the daum casting technique,,,,,did the guy mention what sort of mold material they use there, and how best to remove the mold from the glass,,,,thanks,,,,oh i saw your lizard, GREAT, keep up the great work,,,,rodney

"The clarity of the glass is a function of temp and particle size.
Increase in either gives a more clear result. "


Does this mean that if I increase the final fuse temp, perhaps slow down the fusing to let air escape and use a slightly larger frit (maybe 2 instead of powder) that I can get a significantly more transparent end result?

~N


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Yup! Brock

I think I've died and gone to heaven.... thanks!

~N

As I mentioned PdV is not my speciality. I work with heavy
castings. A sample sched'l:

1. 100 C/h -> 250 Drying and plaster calcination
2. a little faster -> 600 C, to pass the chrystobalite transition and burn the glue.
3. AFAP 715 C
4. soak for about 15-20 mins. PEEK.
5. let the kiln cool off

That was for COE 99 glass!!! BE tems maybe 20 C lower.
too long soak and the glass has time to flow down the mold walls. Too little soak and tack fusing is not complete.
Soak and peek until the rim starts to get watery and smooth.

This is very heat sensitive process, the temps vary with
the kiln calibration, glass type, frit size.

-lauri

In PdV the bubbles are microscopic, with almost no buoyancy. You must cook high and long to get them out.
Mixing a bit coarse frit improves the clarity.

In hand laid PdV the frit is pressed against soft mold.
The surface will not be glossy anyway. That is part of the
charm of PdV.

Has anyone tried the Daum process, that is hot mold?
My *guess* is that if you have a very hot mold with high heat capasity, and fill it with frit, the melting begins
along the mold walls. When it is 1-2 mm deep you
pour the rest of frit away, leaving a glass surface to mature.
This can be made with coarser frit as the mold is initially filled, so the particles can't rumble down the wall.

-lauri

1. I never use powder in my PdV...the colors turn out too dense, opaque, and ugly so if that's what you used for your glass orchid I'm not surprised you didn't like the results. I use frit size 1 and 2.

2. In my conversation with the Daum artist, he said they filled their molds cold with loose dry frit. Don't know how you could fill a hot mold without thermally shocking the mold. I know some people 'charge' their molds during the firing process and I have done that long ago but the results were not good. Better to have all your volume of glass in at the beginning.

3. Don't know specifically what Daum's mold formula is but this topic has been discussed ad infinitum on this board and it basically boils down to plaster and silica. The mold should be soft enough after firing to easily break away.

4. As for the clarity of Daum's work...again frit size matters and also the type of glass. We have learned that there is casting with glass and casting with Bullseye, which we currently use. I imagine Daum uses a more lead based glass as opposed to soda lime. Lead glass casts at lower temps and faster and has more clarity.

5. Higher temps and longer casting times will not let all the tiny bubbles escape from a pate de verre casting. All you will achieve is over-firing with lots of ugly pits and holes in your piece. (The voice of experience here.) Also more crud on the surface from the mold and glass trying to become one.

6. As for what constitutes PdV...the French masters made a paste of their glass and coined the term, so there is your definition. Casting with loose frit is still just casting with glass. What difference if you use lots of little loose chunks or a few big ones. There is still no great control in the placement of colors and that is what pate de verre is about.

E

6. As for what constitutes PdV...the French masters made a paste of their glass and coined the term, so there is your definition. Casting with loose frit is still just casting with glass. What difference if you use lots of little loose chunks or a few big ones. There is still no great control in the placement of colors and that is what pate de verre is about.

E


The line is getting blurry with the melanges of techniques ocurring. I would agree with the above Ellen, with the proviso that the colour is "placed". Specific colours in specific places, like the eyes of fishes, or leaves on a different coloured background. Brock

Specific colours in specific places, like the eyes of fishes, or leaves on a different coloured background

exactly

e