Runny Glaze Pot Saucer Idea

3-D Modeling of saucer design 

       Many very pretty glazes, unfortunately, are plagued by a horrible amount of running. Crystalline glazes, Ox Bloods, Chuns, Rutile Blues, and other various types often can run off the pots that they are on. Personally, my Shorn Base and Permafrost Base (if fluxed by a high amount of colorant) run a lot. This gives me good reason to use saucers, like crystalline glaze potters use, under my pots. The average design, however, for these saucers is just a flat shallow bowl which would then easily fuse the piece to the saucer quite often.
        So, I designed a saucer that I believe could catch all of the glaze dripping, be reusable, and easily made from a press mold. That means that i could easily and quickly make new saucers if one does happen to not be reusable after a firing. By setting the pot on a tripod of points, rather than on the surface of the saucer, the liquid glaze can freely drip down. Higher gaps between points would be smart for larger pots.
       There are a few risks that could be possible with this design though: if the kiln is violent (such as wood, soda, or salt) the pot might fall off the saucers or if the pot has an excessively thin base and is very soft at high temperatures it could create dimples on the bottom of the piece.
        These should be made from a hard, porous clay and cover in kiln wash on the top surface including the points and rim. With the kiln wash, removing glaze drips would be easier making these saucers last for more firings. Any glaze left on the saucer would just melt again in the next firing - eventually leading to a glaze overflow.

The Search For Copper Red

       Copper Red glazes are often hard to find, recreate, or produce. Copper can alter the color of a glaze in multiple ways. Depending on the amount of copper and the makeup of the base glaze, copper glazes can range from teal, to red, to yellow, to peach bloom, to gun metal.

The many faces of Copper Carbonate

       Copper Carb can create red (in reduction) in glazes that have low clay content - less than 10% - high alkaline flux content, contain Tin Oxide in amounts of 1% - 5%, and Copper Carb in amount of 1% - 5%. Heavy reduction aids in their production, however over firing them can burn out the copper leaving them white or tan.

Copper Red Attempt 1

Copper Red Attempt 1:
Flint - 25
Dolomite - 8
Custer Feld - 55
EPK - 7
Borax - 5
-----------------
Tin Oxide - 2%
Copper Carb - 0.5%
Red Iron Oxide - 0.5%


       As all of these tiles were fired under the same schedule and other copper reds were produced under the same schedule, firing was not a probable issue.
        I added Red Iron Oxide to try to help in production of red, but the copper was in too low of a percentage. The 7% EPK also most likely had a negative effect on whether red could have been produced. This base, although unsuitable for copper red, became a nice glossy base called Glossy Frog Skin.

Copper Red Attempt 2

Copper Red Attempt 2:
Flint - 25
Dolomite - 8
Custer Feld - 55
EPK - 7
Borax - 5
-----------------
Titanium Dioxide - 3%
Copper Carb - 2%
Red Iron Oxide - 0.5%

       In this attempt I correctly changed the Tin Oxide to Titanium Dioxde, to see if Titanium would have a positive effect rather than Tin (it did not), however both the Titanium Dioxide and Red Iron Oxide were in too high of percentages. Besides additives, this base did not seem capable of producing a Copper Red, not easily anyway. Rather than producing red, this base was producing yellows, tans, and browns.

Copper Red

Copper Red Attempt 3:

Neph Sye - 45

Flint - 30

Whiting - 8

Spodumene - 17

------------------

Copper Carb - 2%

Rutile - 1%

         For this attempt I changed the base to one that (1) does not include EPK, (2) uses Lithium and Sodium as fluxes instead of Potassium and Boron, and (3) uses whiting to add opacity instead of Dolomite. I also substituted both Red Iron Oxide and Titanium Dioxide or Tin Oxide for Rutile - a material that contains both TiO2 and Fe3O2.

        This recipe succeeded to create a Copper Red glaze that does not run very much and breaks translucent yellow/tan instead of opaque white. It is also an example that good looking glazes are not exclusively made of complex recipes. Sometimes the simplest answer is the best.

Copper Pink - Permafrost 

Copper Pink:

Neph Sye - 45

Flint - 30

Whiting - 8

Dolomite - 10

Talc - 7

-----------------

Copper Carb - 1%

        Copper Red glazes can be varied to create a pink, just be using an opacifier to lighten the glaze. This can be seen in the Permafrost Base with 1% Copper Carb. The permafrost also shows that it is possibly to take a copper red and have it bloom green with more Copper Carb. The only large difference between my Copper Red and this glaze recipe is that Spodumene was substituted to Dolomite and Talc and there is no Titanium Dioxide or Tin Oxide added.

Chemical Differences: Rutile and Ilmenite

        Titanium Dioxide helps to form crystaline structures in glaze melts. The most common materials added to glazes to introduce TiO2 are Titanium Dioxide itself, Rutile, and Ilmenite. Both Rutile and Ilmenite contain a significant amount of TiO2. However, Ilmenite contains more "contaminants" compared to Rutile. On a simplistic level, Ilmenite contains approximately 50% FeO whereas Rutile only contains about 10% Fe3O2. Both also contain other contaminants that are in minute levels.

http://digitalfire.com/4sight/material/rutile_1204.html

http://digitalfire.com/4sight/material/ilmenite_863.html

Rutile: 
Can be found in granular or powdered form. The varied size varies the mottling in the glaze. The most commonly produced colors by Rutile are tan and blue (seed of the glaze name "Rutile Blue"). The Titanium Dioxide in it can inhibit crystal formation (see Permafrost Base, Rutile Line Blend) and the iron in the material can help in fluxing the glaze at high levels. Rutile can also be used to soften the color producted by more potent colorants such as Chrome and Cobalt and variegate the both the texture and color in a glaze (see Satin Base Green).


Ilmenite:
Also can be found in granular or powdered form, however is more common in granular. Can be used in clay bodies or glazes to produce a speckled effect. Like Rutile, can seed Titania crystals in a glaze. The higher amounts of iron in the material can help to flux. Grains of Ilmenite in a glaze can bleed out at higher temperatures, forming dark blemishes. In combination with Rutile, Ilmenite can help to produce the characteristic Rutile streaking and mottling.

Copper, Iron, and Rutile Line Blends

        These line blends show the effects of Copper Carb, Iron Oxide, and Rutile on the Permafrost base as well as the effects of Copper Carb on the Shorn Base. The increments of each line blend consisted of 1% - 5% regardless of colorant or base glaze. 

                   Permafrost Base                                         Shorn Base

                       Neph Sye - 45                                       Wollastonite - 25

                           Flint - 30                                            Spodumene - 25

                         Whiting - 8                                        Cornwall Stone - 25

                       Dolomite - 10                                            Talc - 25

                           Talc - 7

Permafrost Base, Copper Carb Line Blend

      Copper Carb does not flux the Permafrost Base to a noticeable amount, however increased amounts of Copper Carb begin to form very small crystals that sparkle on the satin glaze surface.

Permafrost Base, Red Iron Oxide Line Blend

      The Permafrost Base becomes more and more runny and glossy as higher amounts of fluxing agents are added, such as Red Iron Oxide. The two tiles furthest to the right were so fluid that they ran off the tile.

Permafrost Base, Rutile Line Blend

         Rutile, like Red Iron Oxide, fluxes the Permafrost Base in higher amounts. At 3% the Rutile begins to noticeably crystalize on the surface of the glaze. By 5% it fluxes the glaze enough to add a Hare's Fur like effect.

Shorn Base, Copper Carb Line Blend

     The Shorn Base alone is very runnny, so the effect of any fluxing that the Copper Carb might have caused is not noticeable. Increased amounts do, however, change both the color of the crystals and the glaze matrix. Higher amounts of Copper Carb deepen the teal background and make the crystals gunmetal.

Current Work Waiting to be Fired

Unfired "Scorpion Bowl", Aprox 18"x10"

          During my winter break, I spent time working in the studio at Red Star Studio. These unfired, unglazed pieces are just a few things I've been working on. I'll post the finished pieces, along with others and the tests when they fire.
         The spikes and some forms were inspired by the platelets, surfaces, and occasionally spikiness of insect exoskeletons. I also tried adding relief sculpture to the exterior surface of the piece above.

  

 Unfired "Spiked Mug"

Unfired "Spiked Cup"

       These pieces, along with all of my others, are made from White Stoneware. These pieces show a new technique I have been trying: using slip to create spikes. This technique is done by putting fairly firm slip into a squeeze bottle with an 1/8"-3/4" tip. I squeeze a dollop out, press it to the (plastic-leatherhard) piece, and pull away. I did not de-grog the slip. Be sure to completely mix the slip, though, or clumps could impede on the effect. As the spikes dry, the get skinnier so I add a second or third layer to each. A little warning though, the spikes are fairly sharp fired.

Cone 10 Glaze Test Tiles

        These tiles are from a previous cone 10 reduction gas firing at Red Star Studios in Kansas City, MO. Unfortunately, I cannot explain the firing schedule for the firings there because I don't know them, but they are just normal firings; no soaking, no slow cooling, just basically fired to temp then turned off. All of the tiles are made of White Stoneware and were placed in the middle of the kiln, together.

MC Spodumene

Custer Feldspar - 30
EPK - 28
Whiting - 5
Dolomite - 25
Spodumene - 10
Tin Oxide - 2

 Permafrost  +10% Rutile

Neph Sye - 45
Flint - 30
Whiting - 8
Dolomite - 10
Talc - 7
--------------------
Rutile - 10%

Permafrost +2% Cobalt Carb

Neph Sye - 45
Flint - 30
Whiting - 8
Dolomite - 10
Talc - 7
--------------------
Cobalt Carb - 2%

      

        The Permafrost base is a opaque satin white without colorants. It runs slightly, and more so with added oxides. Exceeding 3.5% Red Iron Oxide is not a good idea because it fluxes the glaze enough to run of the clay like a crystaline glaze. Separated yellow iron crystals form at 4% on a dark brown background. Copper Carbonate does not flux the glaze to a largely noticeable amount and turns the base pink at 1% with increasing flowering of green as you reach 5% until completely green. However, the copper doesn't melt the glaze past a satin in the 1% - 5% tests I did. 

MC Fake Nuka Base

Flint - 30

Custer Feldspar - 37

Bone Ash - 2

Whiting - 23

OM4 - 6

Talc - 2

Base 2A

Cornwall Stone - 46
Whiting - 34
Flint - 20

Base 1

Soda Feldspar - 65
Flint - 20
Whiting - 5
EPK - 5
Dolomite - 5

These white bases are all on the glossier side. The Fake Nuka shows signs of blue iron crystals forming from iron leaching from the clay body - small amounts of Red Iron Oxide (possibly .5%) would make a nice iron blue glaze. Base 2A crackles after firing (as apposed to during ) and thickness increases the strength of the crackle. The black ink on Base 2A is black Sharpie wiped directly after marking on with a wet paper towel.

MC Tomato Red

Flint - 15
Custer Feldspar - 30
EPK - 25
Whiting - 15
Bone Ash - 5
--------------------
Red Iron Oxide - 7
Tin Oxide - 1

MC Copper Red

Neph Sye - 45
Flint - 30
Whiting - 8
Spodumene - 17
--------------------
Copper Carb - 2
Rutile - 1

MC Red Tenmoku
Custer Feldspar - 77
Whiting - 6
Flint - 1
EPK - 4
Gerstly Borate - 13
 --------------------
Red Iron Oxide - 9

        My copper red glaze does not run very noticeably, unlike most oxblood variations. The Tenmoku does run, however, as you can see by the black pool. The running of what would normally be the dark body of a tenmoku glaze allows for the red to show. 

Shorn Base +2% Copper Carb

Wollastonite - 25
Spodumene - 25
Cornwall Stone - 25
Talc - 25
--------------------
Copper Carb - 4%

    

     Shorn Base + 2% Cobalt Carb
      and 1% Copper Carb

     Wollastonite - 25
      Spodumene - 25
      Cornwall Stone - 25
      Talc - 25
      --------------------
     Cobalt Carb - 2%
     Copper Carb - 1%

Seafoam

Custer Feldspar - 40
Whiting - 30
Flint - 15
EPK - 10
Spodumene - 5 
--------------------
Yellow Ochre - 2

        The Shorn base is very runny, just like other crystaline glazes, so be careful with both application and kiln shelf protection. Without colorants it is white on white. Copper Carb gradually changes the glaze from pale teal with lighter teal crystals (at 1%) to a more vivid teal with gunmetal crystals (at 5%). Cobalt produces a dark blue with purple crystals, Iron produces brown and yellow, Chrome produces green and green. Mixing of colorants should produce interesting color combinations between the crystals and the glaze matrix. Increased amount of colorants increases running.

Satin Base +2% Copper Carb
and 3% Rutile

Custer Feldspar - 45
EPK - 25
Whiting - 15
Neph Sye - 15
--------------------
Copper Carb - 2%
Rutile - 3%

         

            Satin Base
         +2% Chrome oxide
         and 3% Rutile

          Custer Feldspar - 45
         EPK - 25
       Whiting - 15
       Neph Sye - 15
       --------------------
       Chrome Oxide - 2%
       Rutile - 3%

Speckle Base
 +1% Cobalt Carb
and 1% Nickle Dioxide

Wollastonite - 6
Custer Feldspar - 28
EPK - 28
Flint - 15
Dolomite - 19
Gerstly Borate - 4
--------------------
Tin Oxide - 1%
Cobalt Carb - 1%
Nickle Dioxide - 1%

        The Satin Base is a simple base the produces simple colors. Additions of Rutile or Titanium Dioxide increase the complexity of the coloring. This base also responds vividly to thickness changes, and doesn't run whatsoever. Less dull colors are easily obtainable by removing the rutile. The Speckled Base runs slightly and darkens where pooled. Change the colorants, but always keep the Tin Oxide as that is what produces the speckling.

Glossy Frog Skin 1

Flint - 25
Dolomite - 8
Custer Feld - 55
EPK - 7
Borax - 5
--------------------
Copper Carb - 4%
Cobalt Carb - 0.5%
Red Iron Oxide - 2%
Titanium Dioxide - 2

           

           Glossy Frog Skin 2

           Flint - 25
          Dolomite - 8
          Custer Feld - 55
          EPK - 7
             Borax - 5    
       --------------------
        Copper Carb - 2%
         Red Iron Oxide - 0.5%
       Titanium Dioxide - 3%

The Glossy Frog Skin Base is a nice glossy base on its own, but it responds well to excessive amounts of colorants - both by quantity of colorants and quantity of percentage of each colorant. Increased colorants enlarged the dotting of colors but also makes it run more. Without excessive colorants, the glaze doesn't noticeably run.