Glaze Crawling Problem - Electric Mid&Hi Fired Ceramics2024-03-28T13:55:32Zhttps://cone6pots.ning.com/forum/topics/glaze-crawling-problem?commentId=2103784%3AComment%3A154748&xg_source=activity&feed=yes&xn_auth=noDonna
In the past I have trie…tag:cone6pots.ning.com,2020-01-07:2103784:Comment:1549762020-01-07T21:00:17.549ZRShttps://cone6pots.ning.com/profile/RonSa
<p>Donna</p>
<p>In the past I have tried wetting the pots like you mentioned, to humid around for it to work well here but thanks for the thought.</p>
<p>I decided to experiment with a different base, while the resulting glaze is really nice it wasn't what I was looking for ( I plan on adding it to my list of glazes I like and use)</p>
<p>After playing around and trying to figure out what went wrong with the batch I'm beginning to think that somehow it got contaminated. I'm going to mix up 500g…</p>
<p>Donna</p>
<p>In the past I have tried wetting the pots like you mentioned, to humid around for it to work well here but thanks for the thought.</p>
<p>I decided to experiment with a different base, while the resulting glaze is really nice it wasn't what I was looking for ( I plan on adding it to my list of glazes I like and use)</p>
<p>After playing around and trying to figure out what went wrong with the batch I'm beginning to think that somehow it got contaminated. I'm going to mix up 500g of fresh glaze to see if this is the case</p> Sorry, also for a recipe like…tag:cone6pots.ning.com,2019-12-28:2103784:Comment:1549612019-12-28T18:20:44.212ZDonna Kathttps://cone6pots.ning.com/profile/DonnaKat
<p>Sorry, also for a recipe like this I made up a second batch with the entire EPK calcined and then mixed the two but I would not do that unless you were having more serious problems (you said only two small pots). You could though for instance just mix up a quarter size batch with all calcined EPK; mix the two and see if that helped. <br></br> <br></br> <cite>Donna Kat said:…</cite></p>
<p>Sorry, also for a recipe like this I made up a second batch with the entire EPK calcined and then mixed the two but I would not do that unless you were having more serious problems (you said only two small pots). You could though for instance just mix up a quarter size batch with all calcined EPK; mix the two and see if that helped. <br/> <br/> <cite>Donna Kat said:</cite></p>
<blockquote cite="http://cone6pots.ning.com/forum/comment/show?id=2103784%3AComment%3A155261&xn_out=json&firstPage=1&lastPage=1&xg_token=930eff633dd28a790309b22808051773&_=1577557054701#2103784Comment155261"><div><p>Wiping with a sponge can cause crawling if the sponge has picked up any dirt/clay, If you are in a dry area (not humid but arid) you can quickly rinse the pot under running water but your glazing technique has to adapt to this. An air gun is better than a sponge or rinse off when they come out of the kiln, let dry and cover loosely with plastic to keep clean.<br/> <br/> <cite>RS said:</cite></p>
<blockquote cite="http://cone6pots.ning.com/forum/topics/glaze-crawling-problem#2103784Comment154748"><div><div class="xg_user_generated"><p>I'm seasonably sure its not skin oils or resist, and I do wipe the pots with a damp sponge before dipping the pot into glaze.</p>
<p><span style="text-decoration: underline;">Glaze Base</span></p>
<p>Ferro Frit 3134............. 29.000 <br/> Silica...................... 26.000 <br/> EP Kaolin................... 22.000 <br/> Minspar 200................. 9.000 <br/> Pioneer 2661 Talc........... 10.000 <br/> Wollastonite................ 4.000 <br/><span style="text-decoration: underline;">Plus Colorants</span></p>
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<p>Do you think maybe 5grams of Calcined EPK and 17 of EPK is enough of a change?</p>
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</blockquote> Wiping with a sponge can caus…tag:cone6pots.ning.com,2019-12-28:2103784:Comment:1552612019-12-28T18:17:31.703ZDonna Kathttps://cone6pots.ning.com/profile/DonnaKat
<p>Wiping with a sponge can cause crawling if the sponge has picked up any dirt/clay, If you are in a dry area (not humid but arid) you can quickly rinse the pot under running water but your glazing technique has to adapt to this. An air gun is better than a sponge or rinse off when they come out of the kiln, let dry and cover loosely with plastic to keep clean.<br></br> <br></br> <cite>RS said:…</cite></p>
<p>Wiping with a sponge can cause crawling if the sponge has picked up any dirt/clay, If you are in a dry area (not humid but arid) you can quickly rinse the pot under running water but your glazing technique has to adapt to this. An air gun is better than a sponge or rinse off when they come out of the kiln, let dry and cover loosely with plastic to keep clean.<br/> <br/> <cite>RS said:</cite></p>
<blockquote cite="http://cone6pots.ning.com/forum/topics/glaze-crawling-problem#2103784Comment154748"><div><div class="xg_user_generated"><p>I'm seasonably sure its not skin oils or resist, and I do wipe the pots with a damp sponge before dipping the pot into glaze.</p>
<p><span style="text-decoration: underline;">Glaze Base</span></p>
<p>Ferro Frit 3134............. 29.000 <br/> Silica...................... 26.000 <br/> EP Kaolin................... 22.000 <br/> Minspar 200................. 9.000 <br/> Pioneer 2661 Talc........... 10.000 <br/> Wollastonite................ 4.000 <br/><span style="text-decoration: underline;">Plus Colorants</span></p>
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<p>Do you think maybe 5grams of Calcined EPK and 17 of EPK is enough of a change?</p>
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</blockquote> Thanks Norm I'll give those s…tag:cone6pots.ning.com,2019-11-14:2103784:Comment:1545542019-11-14T21:22:25.516ZRShttps://cone6pots.ning.com/profile/RonSa
<p>Thanks Norm I'll give those suggestions a try.</p>
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<p>BTW, sorry it took so long to return and view this message.</p>
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<p>Thanks Norm I'll give those suggestions a try.</p>
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<p>BTW, sorry it took so long to return and view this message.</p>
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<p></p> Olive Green Celadon shares ma…tag:cone6pots.ning.com,2019-11-06:2103784:Comment:1546522019-11-06T03:39:01.745ZNorm Stuarthttps://cone6pots.ning.com/profile/NormStuart
<p><strong>Olive Green Celadon</strong> shares many features of your glaze - a runny glaze with too much magnesium.</p>
<p><strong>I think the solution is to replace half the magnesium with calcium - or apply it <span style="text-decoration: underline;">over</span> a calcium glaze with no magnesium.…<br></br></strong></p>
<p><a href="https://storage.ning.com/topology/rest/1.0/file/get/3699387163?profile=original" rel="noopener" target="_blank"><img class="align-left" src="https://storage.ning.com/topology/rest/1.0/file/get/3699387163?profile=RESIZE_710x"></img></a></p>
<p><strong>Olive Green Celadon</strong> shares many features of your glaze - a runny glaze with too much magnesium.</p>
<p><strong>I think the solution is to replace half the magnesium with calcium - or apply it <span style="text-decoration: underline;">over</span> a calcium glaze with no magnesium.<br/></strong></p>
<p><a href="https://storage.ning.com/topology/rest/1.0/file/get/3699387163?profile=original" target="_blank" rel="noopener"><img src="https://storage.ning.com/topology/rest/1.0/file/get/3699387163?profile=RESIZE_710x" class="align-left"/></a></p>
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<p><strong>1.)</strong> Many of the ingredients of the glaze (3134, Talc and Wollastonite) become liquid at a low temperature (around Cone 016) while the rest of the ingredients are still solid;</p>
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<p><strong>2.)</strong> These glazes, and two of the low temperature melters, have a high percentage of magnesium which is used to create crawl glazes due to the high surface tension as George mentioned.</p>
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<p><strong>3.)</strong> These glazes have a very high Silica to Alumina ratio (about 11 to 1) - with means they're very runny, even after everything is melted;</p>
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<p>You've noticed Iron binds readily to clay leaving behind the coloration, but virtually nothing else from the glaze.</p>
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<p>You can see how thick the glaze is where it still remains - because that's where the missing glaze went.</p>
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<p><strong>If you apply a gaze prone to crawling thickly enough, it can be as thick as the surface tension wants to be, so no crawling</strong> - but that turns out to be thicker than you think, as on the bottom of the pot, and not that attractive.</p> I'm seasonably sure its not s…tag:cone6pots.ning.com,2019-10-29:2103784:Comment:1547482019-10-29T15:46:26.333ZRShttps://cone6pots.ning.com/profile/RonSa
<p>I'm seasonably sure its not skin oils or resist, and I do wipe the pots with a damp sponge before dipping the pot into glaze.</p>
<p><span style="text-decoration: underline;">Glaze Base</span></p>
<p>Ferro Frit 3134............. 29.000 <br></br> Silica...................... 26.000 <br></br> EP Kaolin................... 22.000 <br></br> Minspar 200................. 9.000 <br></br> Pioneer 2661 Talc........... 10.000 <br></br> Wollastonite................ 4.000 <br></br><span style="text-decoration: underline;">Plus…</span></p>
<p>I'm seasonably sure its not skin oils or resist, and I do wipe the pots with a damp sponge before dipping the pot into glaze.</p>
<p><span style="text-decoration: underline;">Glaze Base</span></p>
<p>Ferro Frit 3134............. 29.000 <br/> Silica...................... 26.000 <br/> EP Kaolin................... 22.000 <br/> Minspar 200................. 9.000 <br/> Pioneer 2661 Talc........... 10.000 <br/> Wollastonite................ 4.000 <br/><span style="text-decoration: underline;">Plus Colorants</span></p>
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<p>Do you think maybe 5grams of Calcined EPK and 17 of EPK is enough of a change?</p> Your oxide formula doesn't te…tag:cone6pots.ning.com,2019-10-28:2103784:Comment:1547442019-10-28T17:35:13.910ZGeorge Lewterhttps://cone6pots.ning.com/profile/GeorgeLewter
<p>Your oxide formula doesn't tell us about your raw materials. Glazes with high clay content shrink and crack and are somewhat de-adhered while drying. Then at temperature, if the melting glaze has a high surface tension, it tries to ball together, pulling away from clay surfaces with weaker bonding than the force of this surface tension. The solution in this case is to replace raw clay with calcined clay to reduce drying shrinkage. The other classic causes of crawling are skin oils or…</p>
<p>Your oxide formula doesn't tell us about your raw materials. Glazes with high clay content shrink and crack and are somewhat de-adhered while drying. Then at temperature, if the melting glaze has a high surface tension, it tries to ball together, pulling away from clay surfaces with weaker bonding than the force of this surface tension. The solution in this case is to replace raw clay with calcined clay to reduce drying shrinkage. The other classic causes of crawling are skin oils or excessive clay dust on the bisqueware, causing poor adhesion of wet glaze to the bisque body. </p>
<p>Opposite in effect from surface tension are the fuming/wetting properties of a particular glaze. You see this in glazes that will bridge, fill and seal cracks in the clay body and heal over surface defects, or even sealing up over wax resist designs that you wanted to remain unglazed.</p>