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Glaze Chem Question

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#1 yedrow


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Posted 12 September 2013 - 11:11 PM

When using my glaze calc. software I've noticed that I can raise my Al/Si without it affecting my RO numbers in the unity formula. Granting that I will ultimately go out of my limits, outside of those limits is there a rule of thumb about the relationship of fluxes to non-fluxes?



#2 neilestrick


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Posted 13 September 2013 - 08:52 AM


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#3 JBaymore



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Posted 13 September 2013 - 09:22 AM

I am assuming that you are using Flux Unity calculations (there are also other appoaches).  That concept is a core of Herman Seger's original approach....... that the sum of the fluxes always adds up to one.  The software will ALWAYS keep the fluxes set to one... no matter how you adjust the Al/Si ratio.


Some glaze software allows you to change the calculation approach to other options (like Insight).


There ARE "typical limits" for the amouints of Alumina and Silica that a given cone level glaze has in it.  You should be able to find references for them.  For example, Insight has a number of these "Target" formula tables in it for various cone ranges and types of glazes.





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#4 PeterH


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Posted 13 September 2013 - 05:04 PM



If you keep the type of flux constant and vary the alumina and silica in this fashion:



The glaze changes something like this:



I can provide a couple of references if you want them.


Regards, Peter


#5 Biglou13


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Posted 13 September 2013 - 07:07 PM

curse you guys....

(actually thanks)


ive spent over an hour already trying to understand this



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#6 yedrow


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Posted 13 September 2013 - 08:16 PM

Thanks guys, that was extremely helpful. That chart was great Peter! I was kinda getting it, then Biglou posted that link with perfect timing. By going back to the Seger formula on paper I saw the relationship between the alumina and silica to the fluxes as numbers.


Thanks again.



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