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Understanding glazes, frits and raw materials. Advice on a good book needed


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Does anybody have a good real technical book about glazes to suggest? Possibly available online…

I would like to start making my own glazes. As an hobbist I always used only commercial available glazes, but now I found a couple of good source of a quite big range of raw materials for potters where I can get low quantities at a resonable price.

The fact, however, is that I don’t see a big difference between using commercial ready-to-use glazes and slavishly follow a recipe suggested by others…  not to mention that often commercial glazes give better results and are more reliable than recipes found around in the internet...

I would like not to be bounded to a specific raw material, for example. I found many different recipes with many different raw materials, so I would need to buy many different materials. Why this recipe use one frit, or one feldspar and not another one? Can I use the ones I already have in my shelf instead? One example is Gerstley borate. I could get Gerstley borate also here, but it’s quite expensive and notoriously it has some issues. How can I replace it? I already have a Boron-Calcium-Sodium frit, but what are the right amounts to replace Gerstley borate? Then, why for raku glazes one receipe adds 12% Kaolin + 7% silica to the frit, and  another one adds ony 5% of kaolin with no silica? Another use 25% of silica+5% kaolin…  Does the difference is given by the different frits used or does they have a different outcome?  How can I guess the amount of silica, alumina etc needed to make a glaze sutable for a certain cone  or for a raku firing?

I have many unanswered questions and, since I have no chance to take a good course, I’m looking for a book that gives me some answers, not only receipes and examples…

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3 hours ago, andros said:

The fact, however, is that I don’t see a big difference between using commercial ready-to-use glazes and slavishly follow a recipe suggested by others…  not to mention that often commercial glazes give better results and are more reliable than recipes found around in the internet...

For some, commercial glazes are just fine, for some they are problematic, don’t work on their claybody, very expensive, pretty much impossible to correct  because the recipe is unknown, etc...... Glaze chemistry is pretty straight forward but can be tedious and there is a lot to learn and ....... not all things are known so discovery and creation become a thing as well for a lifetime.

Its not for everyone but if you enjoy learning about how clay behaves and want to create a glaze look just not available commercially (there are many) then mixing your own glazes is a thing and glaze calculation helps with designing and substituting one chem for another. It’s definitely not for everyone though. A glaze calculator can help you with substitutions  but the what and why part usually takes lots of knowledge outside the calculator.

Digital fire on the web is a nice learning resource, Glazy.org is free and will calculate various aspects about glazes. Matt Katz runs a decent college level course (Former Alfred University fellow)  on Clay and Glazes that is just that, online  and college level.  These are a few that range from free, to mostly free, to some expense.

I would never return to using commercial glazes  exclusively for many reasons but I enjoy the educational aspect of ceramics so glaze chemistry to me is fun, useful and very economical while allowing me to fit a glaze to my claybody near perfect. I have experienced the frustration of that commercial glaze that crazes and pinholes on my claybody all too often early on and not being able to correct it because the recipe is unknown.

Definitely not  a waste of time for those that enjoy it, definitely a huge difference between commercial, and those question you pose all have answers so it does satisfy those that want to know the answers. Why Silica, why feldspar, why boron etc..... Raku glazes are lowfire for the most and some can respond to surface reduction ........... more glaze chemistry .......... and some combustion science thrown in! I find the knowledge component tends to be  addictive for many as many are inquisitive and just have to know the answer.

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Science for Potters - Linda Bloomfield

Ceramic Glazes Cullen - W. Parmelee

A Handbook to Pottery Glazes - David Green

Cushing’s Handbook - Val Cushing

As for calculation software, Digitalfire's Insight is ok but doesn't plot results on the Stull Chart. It requires a subscription.

Hyperglaze is ok too and will plot glazes on the Stull Chart. It runs best on a Mac though. Richard Burkett is offering it free during this %^#*@ pandemic.

Glazy.org has become an online cornerstone along with the Digitalfire refernce library. The software at Glazy is well put together and easy to negotiate. The Stull chart adjusts as ingredients are added or changed which is a nifty feature.

All three offer much more more than my short description. Glazy in particular makes it easiest to find materials with similar compositions.

Edited by C.Banks
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1 hour ago, Callie Beller Diesel said:

A Potter’s Dictionary by Hamer and Hamer is available through that big online South American river place. I got it for $80 something Canadian, and it’s well worth the price.

 

This can be found on the used market for 20 bucks sometimes, that's where I got mine.  For some reason out of print books on amazon are nutty expensive!

Here's a good deal and only 8 dollars shipping to Canada and 1 dollar shipping to US: https://www.biblio.com/book/potters-dictionary-materials-techniques-frank-hamer/d/458882701?aid=frg&currency_id=1&gclid=Cj0KCQiAyJOBBhDCARIsAJG2h5dDam_b81Hvavl3ZKOUwtedDti6jkGApScuwiXMntI7jgt_AiSFCPYaAuOGEALw_wcB

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Thank you all for your suggestions!

For me actually even the “technical” and theoric aspect of glazes would be very intersting. I’m a material engineer and I attended some course of adavanced ceramics during univerity, and they were definitely interesting. Unfortunatelly (and obviously) these courses had a complitely different point point of view, and materials as well were different in some extent, because for example fluxes and glass formers are complitelly banned in engineering ceramcis. So about “artistic” cermaics I’m almost complitelly illiterate. I know that experimentation is the only way to get real results, but a theoretical base would be at least a starting point just not to do things completely at random.

I'm going to take a look and get at least one of these books, even if I'll let you figure out the shipping costs to Italy ...!!

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Just a question about  Potter’s Dictionary by Hamer and Hamer. Used copies purchased in US are more cheap than a new copy bought on Amazon, even with the shipping cost to Italy. But the new copy  (6th edition,  2015)  doesn't cost that much more to me. Does it worth paying more for a newer copy or could the 1993 edition be just as good?

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20 hours ago, andros said:

Just a question about  Potter’s Dictionary by Hamer and Hamer. Used copies purchased in US are more cheap than a new copy bought on Amazon, even with the shipping cost to Italy. But the new copy  (6th edition,  2015)  doesn't cost that much more to me. Does it worth paying more for a newer copy or could the 1993 edition be just as good?

You might see if there are copies available in UK, might be even cheaper.  Hamer and Hamer are a british couple if I remember right.

I have the 1986 version and it is fascinating.  Another one that is a fascinating read along the same lines is "advanced ceramic manual: technical data for the studio potter" by john w. Conrad

Edited by liambesaw
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On 2/12/2021 at 8:19 AM, andros said:

Thank you all for your suggestions!

For me actually even the “technical” and theoric aspect of glazes would be very intersting. I’m a material engineer and I attended some course of adavanced ceramics during univerity, and they were definitely interesting. Unfortunatelly (and obviously) these courses had a complitely different point point of view, and materials as well were different in some extent, because for example fluxes and glass formers are complitelly banned in engineering ceramcis. So about “artistic” cermaics I’m almost complitelly illiterate. I know that experimentation is the only way to get real results, but a theoretical base would be at least a starting point just not to do things completely at random.

I'm going to take a look and get at least one of these books, even if I'll let you figure out the shipping costs to Italy ...!!

As you have a background in materials ...

Have you read Zachariasen's 1932 paper, sort of Pauling's bond theory meets glasses? https://pubs.acs.org/doi/abs/10.1021/ja01349a006

Richard Brow https://web.mst.edu/~brow/ used to host an interesting  series of "student notes", I can only see a couple at the moment
https://web.mst.edu/~brow/pdf_structure1.pdf
https://web.mst.edu/~brow/pdf_structure2.pdf

Segar's unity formula tries to capture some of this https://digitalfire.com/article/glaze+chemistry+basics+-+formula%2C+analysis%2C+mole%25%2C+unity%2C+loi
... but has severe limitations with some elements that don't fit neatly into their assigned columns.

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On 2/13/2021 at 5:07 AM, Bill Kielb said:

Interesting, why were they banned and when was this?

Glass makers are banned because engineering ceramics must be complitelly cristalline. Glass phase is amorpous and embrittles them. Electrical characteristincs of some ceramics need a crystalline stucture as well. At the same time glass phase is relatively low melting  and some engineering ceramics must face very high temperatures during service. For this reason sintering is almost always "dry" and made at very high temperatures. I know that there's some exception,  but this is the guideline...

On 2/13/2021 at 4:48 PM, PeterH said:

As you have a background in materials ...

Have you read Zachariasen's 1932 paper, sort of Pauling's bond theory meets glasses? https://pubs.acs.org/doi/abs/10.1021/ja01349a006

Richard Brow https://web.mst.edu/~brow/ used to host an interesting  series of "student notes", I can only see a couple at the moment
https://web.mst.edu/~brow/pdf_structure1.pdf
https://web.mst.edu/~brow/pdf_structure2.pdf

Segar's unity formula tries to capture some of this https://digitalfire.com/article/glaze+chemistry+basics+-+formula%2C+analysis%2C+mole%%2C+unity%2C+loi
... but has severe limitations with some elements that don't fit neatly into their assigned columns.

Thank you Peter, I'll take a look for sure! 

In the meanwhile I've ordered the Potter’s Dictionary by Hamer and Hamer, I can't wait to receive it!

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4 hours ago, andros said:

Glass makers are banned because engineering ceramics must be complitelly cristalline

Interesting, I am familiar with ECAS research of the 80’s and 90’s for  production of some electrical hardware and specialized ceramics coatings etc.....  Here in the states, traditional  glass and ceramics have been widely used along with glaze for many electrical ceramic materials however polymer or EPDM hybrids are being formulated and tested currently. I  think you will find much of  pottery ceramics originates in the 1800’s if not even earlier and is a simple melting process with heat and flux to reduce the heat needed. Old work is often still very pertinent and form the basis of what we do today.

A couple I can think of and suggest:

Ceramic Science for the potter - W.G. Lawrence (Willis - Grant) 1916-

Ceramic Glazes - Cullen W. Parmelee (Industrial Publications Inc.) 1951-

Lots of interesting reading for sure.

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