Hello!
Does anyone have personal experience with the raw blocks of optical glass from http://www.xyzglass.com/rawblocks.html ?
Could you please share impressions, important moments, concerns?
Thanks!
Lucho
Optical Glass from XYZ
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lucho/lachezar/
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lucho/lachezar/
- Posts: 15
- Joined: Tue Aug 03, 2004 12:46 pm
- Location: bulgaria
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Re: Optical Glass from XYZ
I notice several contradictions in the papers that come along with it and as i'm going to fire something very big the length of the whole program may vary more than 2 weeks...
1. Softening Point - according to the "Glass Properties.doc" paper it is 704C, but in the E-book and in the "Melting Parameters" excel table it is 697C!
2. Annealing Point in the "Glass Properties.doc" is 547C, then there is Transformation Point in the E-book and in the "Melting Parameters" excel table that is 535C and in the Firing Curve pdf it is 475C. This is a very big difference!
3. The Coefficient of Linear Thermal Expansion 98 in "Glass Properties.doc" and 99 in the E-book and in the "Melting Parameters" excel table, but here it does not indicate the temperature range!
4. The Strain Point is not listed in any of the papers ...
The measures of the glass blocks also vary little in the different papers, which questions the given Density of 2.56... !
The reason I post this here (apart from asking my supplier) is that I'm not so sure I'll receive an adequate answer to my questions... The glass originates from China and is distributed to Europe by a Checz company. The owner is a very friendly lady but with very limited English and obviously with very limited knowledge about glass.
Any ideas how to manage my firing cycle?
Cheers!
Lucho
1. Softening Point - according to the "Glass Properties.doc" paper it is 704C, but in the E-book and in the "Melting Parameters" excel table it is 697C!
2. Annealing Point in the "Glass Properties.doc" is 547C, then there is Transformation Point in the E-book and in the "Melting Parameters" excel table that is 535C and in the Firing Curve pdf it is 475C. This is a very big difference!
3. The Coefficient of Linear Thermal Expansion 98 in "Glass Properties.doc" and 99 in the E-book and in the "Melting Parameters" excel table, but here it does not indicate the temperature range!
4. The Strain Point is not listed in any of the papers ...
The measures of the glass blocks also vary little in the different papers, which questions the given Density of 2.56... !
The reason I post this here (apart from asking my supplier) is that I'm not so sure I'll receive an adequate answer to my questions... The glass originates from China and is distributed to Europe by a Checz company. The owner is a very friendly lady but with very limited English and obviously with very limited knowledge about glass.
Any ideas how to manage my firing cycle?
Cheers!
Lucho