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Old 04-03-2005, 10:25 PM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
The Old Gaffer
Join Date: Apr 2002
Location: Chocorua New Hampshire
Posts: 21,958
Pete VanderLaan is on a distinguished road
the term "set-up" is not a good one to use really. The dfferences here are ones of viscosity and annealing point which go hand in glove. I was simply trying to demonstrate how one can have most of their ducks in a row in most instances but there will still be exceptions that will give you trouble..

John knows that while I really respect the trident seal that I think it is so sensitive that the sample breaks very easily unless it is damn close in the first place. A lot of what I am looking for is methodology that lets a studio glassmaker analyze their process in a variety of approachable ways. The polarimeters that John uses run a couple grand and while I don't deny the accuracy of the system, I don't think many private studios are going to be willing to make that investment It is where I think the ring test is a very good indicator for not a lot of cash. I think the trident makes sense for major manuafacturers like John but I don't think it's necessary for people who want to make their own colors in house. It is really still the case that if a piece survives the diamond saw while making the ring, the piece is effectively compatible. The ring gives the very fine tuning indicators in the same sense that John's trident seal does the same, or at least that's my opinion.

As to the fusers, I think that bullseye effectively guarantees compatibility within a closed system and that makes perfect sense. Spectrum apparantly does the same thing but by calling their product system 96, the implication is there that any glass hawked as a 96 L.E.C. is going to fit right in. It won't. The fact remains though that the bulk of glasses being produced today have to acknowledge what John calls the Titannic in the room which is SP87 which I think still has a clear majority of market share in commercial batches in this country. Even if it doesn't, the other manufacturers are still shooting at 96 and their annealing points and viscosities are really not far away from Spruce Pine. If they were, we would really be hearing about compatibility issues all of the time and we aren't. The cullets are another story.

And yes the weight survives grinding and sawing just fine.
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