Judith B Posted January 28, 2015 Report Share Posted January 28, 2015 Hello, I need some help! I work for a potter who uses a very finicky stoneware: when it is bisqued, any contact with water (whether it's my hands that are not perfectely dry, or a sponge) will leave a dark stain after the firing. I am not sure I understand why but it makes the glazing quite difficult. For a lot of pieces, she only glazes the inside and so sometimes it spills outside when I pour it out, or even the rim needs to be cleaned. But if I wipe it off with a sponge, it will leave that ugly stain. So I don't know how to clean the glaze in the unwanted places without screwing up everything. I tried to scrape it with a knife and then sand lightly but I'm not sure if it will be enough to take all the glaze off. I'll have the result in a couple of days. But if you have any recommendations, I'd love to hear about it! Link to comment Share on other sites More sharing options...
Frank Hott Posted January 29, 2015 Report Share Posted January 29, 2015 I don't wax. I use a Dremel with 511 easylock coarse and medium grit finishing abrasive pads....lots of control! But then, I don't dip, I brush. Wear an OSHA approved mask. Link to comment Share on other sites More sharing options...
rayaldridge Posted January 29, 2015 Report Share Posted January 29, 2015 Weird. The first thing I would do is ask the potter why this is happening. A couple possibilities occur to me. Is the stoneware pale? If so, maybe the local water has a high iron content, and you could use distilled water to sponge off the g;aze. The other is that the glaze may have soluble ingredients in it, and they soak into the body. It's barely conceivable that getting the outside wet allows those solubles to migrate through from the inside. Link to comment Share on other sites More sharing options...
Callie Beller Diesel Posted January 29, 2015 Report Share Posted January 29, 2015 What clay body is she using? Link to comment Share on other sites More sharing options...
neilestrick Posted January 30, 2015 Report Share Posted January 30, 2015 This is odd. Photos, please. Link to comment Share on other sites More sharing options...
Judith B Posted February 1, 2015 Author Report Share Posted February 1, 2015 I'll try to take some photos next time. She uses a stoneware that's beige after firing. Here are a couple pictures of how it looks like : http://instagram.com/p/vBzEhhKuHi/?modal=true http://instagram.com/p/vweVwiquHw/?modal=true Maybe it could be the water yeah, that would be a good thing to investigate for sure! In any case, since I am not so good at dipping and always end up with glaze all over the place, (I am working on it, I swear) I wish I knew what was going on. But she also uses some Bmix stoneware and this one doesn't have the same reaction, it happens only with that specific stoneware. So I would tend to say it would be the clay. I don't know. I'll check what kind of clay she uses too Link to comment Share on other sites More sharing options...
Callie Beller Diesel Posted February 2, 2015 Report Share Posted February 2, 2015 It looks kinda like the h400 series out of Plainsman. It's a mix high in local clay that does all kinds of fun things with fluorescing. You could call Plainsman to help troubleshoot (they are the guys that run Digitalfire), but if it is in that 400 series, your boss has already given you the best solution: don't get it wet. (400 series is better for sculptural use because it tends to be quite porous, even when mature. It is possible to use it for functional purposes; they just recommend A well-fitted glaze If you go that direction.) Link to comment Share on other sites More sharing options...
Judith B Posted February 8, 2015 Author Report Share Posted February 8, 2015 So I finally got a chance to check, and this is a Laguna clay, the wc-871 Calico clay. I tried to check online but I couldn't find any infos about this issue with water. This thing is really puzzling me! Link to comment Share on other sites More sharing options...
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