Babs Posted February 2, 2014 Report Share Posted February 2, 2014 Frit 3110 50 Silica 200 30 Zinc oxide 20 Nickel oxide 2 Red iron oxide 1. Using it on a white body. ANy confirmation or explanation for unreliability of this glaze? Here are t he results of the nickel glaze posted in another post I fired to C 5 I dipped the vase foot first to the star of the neck. I then dipped the vase from rim down to under the shouilder. I filled the interior and rolled around rim and emptied interior. Wherer the glaze is double thickness it is shiny and tan. Where it os 1 coat, it is very matt and , yes , blue. I now think that nickel is in fact pretty refractory. Can anyone explain the shiny tan colour obtained form double glazing. I think the glaze needs a higher temp to soften the nickel when 1 coat is applied. Any thoughts? Link to comment Share on other sites More sharing options...
bciskepottery Posted February 2, 2014 Report Share Posted February 2, 2014 I ran your recipe through Glazemaster and got the following results: Recipe Name: babs Cone: 5 Color: Firing: Surface: Amount Ingredient 50 Frit--Ferro 3110 30 Silica 20 Zinc Oxide 100 Total Additives 2 Nickel Oxide 1 Iron Oxide--Red Unity Oxide .282 Na2O .028 K2O .128 CaO .562 ZnO 1.000 Total .042 Al2O3 .043 B2O3 0 Fe2O3 2.467 SiO2 58.3 Ratio 81.2 Exp Comments: ----------------------------------- Calculations by GlazeMasterâ„¢ www.masteringglazes.com ------------------------------------ If I read the data correctly, the silica to alumina ratio is high and (likely) problematic, in terms of durability. The coefficient of expansion (81.2) tends toward the high side, also, and might result in fit problems with some clay bodies not of a similar COE range. You could perform a quick durability check by doing a lemon/orange test to see if you get discoloration. Using a finer mesh Silica (325 instead of 200) might get a smoother melt at Cone 5. And, I'm open to others viewpoints on interpretation of data. Link to comment Share on other sites More sharing options...
Norm Stuart Posted February 2, 2014 Report Share Posted February 2, 2014 Babs - I made up a batch of your Teal Blue Breaking Honey. I added 4% Bentonite to this "glaze" as there's no clay-like ingredients to suspend this glaze, or harden it as it dries to keep it from brushing off the bisque. How do you apply this yourself? Is it possible there used to be an additional ingredient, like 10% Kaolin? ? In any event this get's fired to cone 6 tomorrow, so I'll have photo of a test tile to post on Monday. I'm looking forward to the results as I've never seen another glaze chemistry quite like this. Based on past experience, 50% 3110 Frit which melts at Cone 08 should provide more than enough flux to get this all melted at ^6, unless much of the frit fell off the bisque. As you saw in my nickel carbonate test tiles, nickel most often produces an Amber Yellow color. If it is slow-cooled greenish crystals of various types form. Digitalfire says that a combination of Nickel and Zinc Oxide produce Steel Blue and with larger amounts of Zinc Oxide with Nickel produce Lavender Blue, but it doesn't explain why. I not currently aware of any mineral made of zinc, nickel and silica which is blue - so I'm at a loss to explain why this high combination of zinc and nickel reflects blue. Obviously because of the shape of the crystals, but what they are I haven't a clue. Please remember that today is still Saturday in California, so you can look forward to a photo on your Tuesday. Frit 3110 50 Silica 200 30 Zinc oxide 20 Nickel oxide 2 Red iron oxide 1. Using it on a white body. ANy confirmation or explanation for unreliability of this glaze? Here are t he results of the nickel glaze posted in another post I fired to C 5 I dipped the vase foot first to the star of the neck. I then dipped the vase from rim down to under the shouilder. I filled the interior and rolled around rim and emptied interior. Wherer the glaze is double thickness it is shiny and tan. Where it os 1 coat, it is very matt and , yes , blue. I now think that nickel is in fact pretty refractory. Can anyone explain the shiny tan colour obtained form double glazing. I think the glaze needs a higher temp to soften the nickel when 1 coat is applied. Any thoughts? Link to comment Share on other sites More sharing options...
Babs Posted February 2, 2014 Author Report Share Posted February 2, 2014 Thanks to you both, quite interesting as it is in my old notebook as a glaze suitable for domestic ware. Where it is steel blue it is matallic and quite unattractive as domestic ware, can hear the knives scraping now! I apply it by stirring well between dips and handling carefully, as you state it is soft and powdery when applied and bentontite would help with this and suspending the nickel oxide. ANd where thick it reverts to tan!! Poss nickel at bottom of bucket for second dip. AAlso noted that slow cooling may produce lavendar crystals. Interesting glaze but i'll leave it off the dinnerplates. Link to comment Share on other sites More sharing options...
Norm Stuart Posted February 2, 2014 Report Share Posted February 2, 2014 Based on what Digitalfire says, extremely high levels of zinc create such a matte crystallization on the surface of the glaze that cutlery easily marks it, just as you say. From my experience, simply mixing 3110 frit with 2% green nickel oxide or 3.6% nickel carbonate will result in the amber honey melt. The 1% added red iron oxide will possibly change the glaze color slightly - but I've found that red iron oxide, at cone 6 and below, first preferentially binds with the clay body, leaving only the surplus from this reaction to remain in the glaze melt. For this reason an iron glaze on an iron rich clay will look different to the same glaze on a white clay. You can see this layer of iron oxide on a white clay under the glaze melt by snapping in half a white test tile with an iron containing glaze on it. The blue area of the glaze is obviously zinc-nickel-something. Thanks to you both, quite interesting as it is in my old notebook as a glaze suitable for domestic ware. Where it is steel blue it is metallic and quite unattractive as domestic ware, can hear the knives scraping now! I apply it by stirring well between dips and handling carefully, as you state it is soft and powdery when applied and bentontite would help with this and suspending the nickel oxide. And where thick it reverts to tan!! Poss nickel at bottom of bucket for second dip. Also noted that slow cooling may produce lavender crystals. Interesting glaze but I'll leave it off the dinner plates. Link to comment Share on other sites More sharing options...
Babs Posted February 2, 2014 Author Report Share Posted February 2, 2014 It is so matte and so shiny to the point of crazing when studied close up in the amber section which is double dipped. Sure there is a use for this but not what I'm after at t he mo. Link to comment Share on other sites More sharing options...
Babs Posted February 3, 2014 Author Report Share Posted February 3, 2014 I ran your recipe through Glazemaster and got the following results: Recipe Name: babs Cone: 5 Color: Firing: Surface: Amount Ingredient 50 Frit--Ferro 3110 30 Silica 20 Zinc Oxide 100 Total Additives 2 Nickel Oxide 1 Iron Oxide--Red Unity Oxide .282 Na2O .028 K2O .128 CaO .562 ZnO 1.000 Total .042 Al2O3 .043 B2O3 0 Fe2O3 2.467 SiO2 58.3 Ratio 81.2 Exp Comments: ----------------------------------- Calculations by GlazeMasterâ„¢ www.masteringglazes.com ------------------------------------ If I read the data correctly, the silica to alumina ratio is high and (likely) problematic, in terms of durability. The coefficient of expansion (81.2) tends toward the high side, also, and might result in fit problems with some clay bodies not of a similar COE range. You could perform a quick durability check by doing a lemon/orange test to see if you get discoloration. Using a finer mesh Silica (325 instead of 200) might get a smoother melt at Cone 5. And, I'm open to others viewpoints on interpretation of data. That Al:Si ratio is high, ANd yes the CoE too, htere is crazing occurring where the double dip is at the shoulder of hte pot, amber glassy section, HMM Need to fiddle and TEST. Link to comment Share on other sites More sharing options...
Norm Stuart Posted February 4, 2014 Report Share Posted February 4, 2014 Babs - What you're dealing with is a Macro-Crystalline glaze which produces Zinc Crystals colored blue with Nickel. In the very runny 3110 frit background, which is why macro-crystalline glazes are placed on catchers, the Nickel colors the frit brown, just as it does in my other Nickel glazes. I tried it on both white and brown clay test tiles, with a six hour slow-cool between 982 C and 852 C. For larger blue areas, I'd suggest you placed a lot more of the zinc on those areas. I have no idea what role the 1% Red Iron Oxide plays, perhaps nothing or perhaps a nucleation role in the crystals. Below, the same percentage of Nickel Carbonate in Ferro 5301 Frit fired to Cone 04. 50 Frit 3110 30 Silica 200 20 Zinc oxide 3.2 Nickel Carbonate 1 Red iron oxide 4 Bentonite Using it on a white body. ANy confirmation or explanation for unreliability of this glaze? Here are t he results of the nickel glaze posted in another post I fired to C 5 I dipped the vase foot first to the star of the neck. I then dipped the vase from rim down to under the shouilder. I filled the interior and rolled around rim and emptied interior. Wherer the glaze is double thickness it is shiny and tan. Where it os 1 coat, it is very matt and , yes , blue. I now think that nickel is in fact pretty refractory. Can anyone explain the shiny tan colour obtained form double glazing. I think the glaze needs a higher temp to soften the nickel when 1 coat is applied. Any thoughts? Link to comment Share on other sites More sharing options...
Babs Posted February 4, 2014 Author Report Share Posted February 4, 2014 Babs - What you're dealing with is a Macro-Crystalline glaze which produces Zinc Crystals colored blue with Nickel. In the very runny 3110 frit background, which is why macro-crystalline glazes are placed on catchers, the Nickel colors the frit brown, just as it does in my other Nickel glazes. I tried it on both white and brown clay test tiles, with a six hour slow-cool between 982 C and 852 C. For larger blue areas, I'd suggest you placed a lot more of the zinc on those areas. I have no idea what role the 1% Red Iron Oxide plays, perhaps nothing or perhaps a nucleation role in the crystals. Interesting results I experienced NO run. Check the bottom of my pot. My larger blue areas were a single dip. ie into the shoulder of pot from foot, and out, no delay as I bisque fire to C06 so pot is quite porous. The tan area of the shoulder and rim were double dipped from rim. Any blue on the pot above were single dips! The blue on top of rim came where i poured the extra glaze from interior over dipped glaze thus washing it off as the dipped glaze was still damp. No crystals of significant size fast cooling all the way. ALCHEMY. Going to test with adding EPK and jiggling formula when next I have a time in shed, getting the CoE down for a start to prevent crazing and altering the Al:Si ratio to see what that does to the appearance Link to comment Share on other sites More sharing options...
Norm Stuart Posted February 4, 2014 Report Share Posted February 4, 2014 Adding 4% Bentonite to your macro-crystalline glaze allowed me to put on a thicker layer of glaze. At Cone 6 Ferro Frit 3110 is pretty watery. I dipped the cylinder in the glaze 3 times. So you can expect a lot of running over a six hour slow-cool. Fortunately we use Kiln Wash which is 50% Alumina Hydrate and 50% EPK, so excess glaze merely lifts off attached to the ware. This is another very similar recipe for a macro-crystalline glaze. The person using this makes this glaze twice, once with 3134 and the other with 3110. He applies the 3134 first, then applies the layer with 3110. 103.0% Macro Crystalline Base -- Cone 6 52.0% Ferro Frit - 3110 or 3134 50% 24.0% Zinc Oxide 20% 24.0% Silica 325 Mesh 30% 2.0% Lithium Carbonate 0% 1.0% Titanium Dioxide 1% Red Iron Oxide - Maybe these are a nucleation agents or it night be unnecessary. 0.5% to 4.0% Coloring Oxide, Cobalt, Copper, Nickel. Just compare how close this recipe is to your Teal Blue breaking Honey - except they use 24% Zinc Oxide instead of 20%. The background color of your glaze is nearly identical to this excess of Nickel Carbonate mixed with Ferro 5301 Frit. Babs - What you're dealing with is a Macro-Crystalline glaze which produces Zinc Crystals colored blue with Nickel. In the very runny 3110 frit background, which is why macro-crystalline glazes are placed on catchers, the Nickel colors the frit brown, just as it does in my other Nickel glazes. I tried it on both white and brown clay test tiles, with a six hour slow-cool between 982 C and 852 C. For larger blue areas, I'd suggest you placed a lot more of the zinc on those areas. I have no idea what role the 1% Red Iron Oxide plays, perhaps nothing or perhaps a nucleation role in the crystals. Interesting results I experienced NO run. Check the bottom of my pot. My larger blue areas were a single dip. ie into the shoulder of pot from foot, and out, no delay as I bisque fire to C06 so pot is quite porous. The tan area of the shoulder and rim were double dipped from rim. Any blue on the pot above were single dips! The blue on top of rim came where i poured the extra glaze from interior over dipped glaze thus washing it off as the dipped glaze was still damp. No crystals of significant size fast cooling all the way. ALCHEMY. Going to test with adding EPK and jiggling formula when next I have a time in shed, getting the CoE down for a start to prevent crazing and altering the Al:Si ratio to see what that does to the appearance Link to comment Share on other sites More sharing options...
Babs Posted February 4, 2014 Author Report Share Posted February 4, 2014 The iron softens the colour of the blue obtained, becomes a greyer blue. Thanks, but really looking for a domestic glaze with these colour variations, not going for the spekky stuff! As you obtained, the iron would give a good colour of glaze to contrast the blue crystals, old colour wheel stuff. Link to comment Share on other sites More sharing options...
Norm Stuart Posted February 4, 2014 Report Share Posted February 4, 2014 I'd be willing to bet that if you snapped one of these tiles in half, you'd see the line of red iron which has bound to the white clay. Using just 1% red iron oxide doesn't leave much for the glaze melt after the white clay is done binding. I'm fairly certain that this glaze fired would look identical without the red iron oxide. The major difference is the wet glaze will no longer look pink. I don't see a difference in color using only Nickel Carbonate with frit, except that the white clay looks whiter. The iron softens the colour of the blue obtained, becomes a greyer blue. Thanks, but really looking for a domestic glaze with these colour variations, not going for the spekky stuff! As you obtained, the iron would give a good colour of glaze to contrast the blue crystals, old colour wheel stuff. Link to comment Share on other sites More sharing options...
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