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Min

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  1. Like
    Min got a reaction from Callie Beller Diesel in Rough shipping   
    And Canada Post will not cover any damage to ceramics regardless of how well it's packed.
  2. Like
    Min reacted to Callie Beller Diesel in Rough shipping   
    Keep in mind that the OP is in Canada, folks. As much as we may complain about it, Canada Post is less expensive to ship with than the big courier services are, unless you’re doing a LOT of volume. Even with ICAN benefits. And my customers pay the shipping too. 
     
    And it’s worth noting that all shipping services are coping with larger volumes while having to cope with a pandemic. There’s going to be slow downs and errors, just like at Christmas. 
  3. Like
    Min reacted to TSmith in Anyone using (or used) Laguna WC611 #70 ?   
    I use both Standard #112 (as well as its sister clay #225) and Laguna #70.  They are very different clays, but not in a bad way.  #70 might be my all time favorite clay if I only had one to choose from.  It throws very "slippy", that it the only way I can think to describe it.  It doesn't need a lot of water and it does have a good bit of grog in it, yet it doesn't really feel that way when throwing.  I have been able to fix mistakes while throwing #70 that I couldn't do with #112 or any other clay that I have used over the years. The most extreme was when a low/wide bowl "sat down" and I was able to lift it back up, let it dry a little and then finished the bowl.  I would not be able to do that with #112.
    It takes glazes like a dark clay and I really love the richness of it.  For a long time I was the only student using it until I started doing a lot of glaze combination experiments and other students loved my finished pieces and started using it as well. It is also a dream to throw after a good aged reclaim.
  4. Like
    Min got a reaction from Hulk in Orton Cone Charts   
    I do remember that thread Tom, it's what made me question what the info on the cone charts says. The blurb with the charts is reading the opposite of what the Orton Booklet is, hopefully they will change the oversight. I emailed them, will update my post if they change anything.
  5. Like
    Min got a reaction from kjharris in Kiln Help   
    Really good detailed plans for converting an electric to a downdraft here. The author, Boris Robinson, has an article in the April 2020 Ceramics Monthly. 
  6. Like
    Min reacted to Hulk in Orton Cone Charts   
    Recall we received clarification from Orton on small vs large cones: 
          https://community.ceramicartsdaily.org/topic/21668-kiln-sitter-cone-for-witness-cone
    The website was corrected (the .pdf was ok)
          The small cone description has been changed on Orton's website, now reads (emphasis added) "Small Cones used on the kiln shelf deform at about 9°F after Large or Self-Supporting Cones of the same number."
    My take is still (mostly) repeatability - how the glaze and clay behaves when cone is bent thus, hence difference between large and small cones matters when a) switching to the other cone type (I like the small ones) and/or b) when sharing firing info with others.
  7. Like
    Min got a reaction from Hulk in Orton Cone Charts   
    Seems we are shifting between Celsius and Fahrenheit a fair bit so I'm adding Links to Orton Cone Charts in both to save people looking them up who might not be fluent in both. If anyone needs it there is some really good information regarding the behaviour of cones and how the rate of temperature increase during the final 1 1/2 - 2 hours of the firing effects the final cone, also on the links below.
    Orton Cone Chart in Fahrenheit
    Orton Cone Chart in Celsius
    edit: There seems to be an error in the information regarding small cones in the above information to the right of the charts. "Typically, small cones will deform 7-10 degrees C earlier than a self-supporting cone, so the temperature values for a self-supporting cone can be used to determine an equivalent small cone temperature by subtracting 7-10 degrees C (or 12-18 degrees F)." This contradicts what it says in the Orton Cone Firing Booklet: "While not recommended, Orton Small Cones can also be used on the kiln shelf in place of larger cones. Because they are smaller, higher temperatures and more heat are required for them to bend (see page 19). When used in this way, the Small Cones require mounting in cone holders or plaques." 
  8. Like
    Min got a reaction from Bill Kielb in Witness cones   
    How quickly did the temperature rise during the final 1 1/2 - 2 hours? If your elements are getting old and worn the kiln can struggle to get to your target temp therefore the longer time spent getting there can amount to more heatwork and cause overfiring. Also, did you have a soak at the end of the firing? That too will cause more heatwork.
  9. Like
    Min reacted to Pres in Watering Down Georgie's and Coyote Commercial Glazes   
    Faith,
    Watering down, depends on what you are going to do with them. If dipping, I used to water bottled Amaco glazes down to the thickness of chocolate milk. However, if you are going to brush on, you would want to get a good brushing consistency that you would do on ware that has recently been washed with a damp sponge. Washing puts a small amount of moisture into the piece so that it does not suck the water out of glaze so fast that you get a poor glaze surface. Experimenting, and testing on test pieces is really the best answer to the amount you water down, along with the number of brush coats you put on. I used to tell my students that 2 brush coats=1 dipped coat, but then again that was for the thickness that I mixed my glazes, but a good rule of thumb.
    All of this IMHO.
     
     
    best,
    Pres
  10. Like
    Min got a reaction from Hulk in sulfur stains on bisque   
    I have the yellowing on bisque every time I use a liner glaze and leave the pot dry overnight before glazing the outside. Soluble minerals carried through the clay from the liner glaze, perhaps a bit from the water in the glaze. Never seen any negative effects from it.
  11. Like
    Min got a reaction from Callie Beller Diesel in Frit 3124 vs. Frit 3134   
    @Wildwoods, original Ron Roy ^6 Majolica recipe using 3124 is here on Glazy. https://glazy.org/recipes/6816
  12. Like
    Min got a reaction from Bill Kielb in Frit 3124 vs. Frit 3134   
    @Wildwoods, original Ron Roy ^6 Majolica recipe using 3124 is here on Glazy. https://glazy.org/recipes/6816
  13. Like
    Min got a reaction from Pres in The verdict on plaster in clay firing   
    Size of the plaster pieces plus absorption of the clay is going to factor into it. In order for the lime to "pop" it needs to be a big enough nodule to create the force needed to blow out the clay covering it when it expands from moisture absorption. Bisque and low fire earthenware is going to be most likely to have issues with blow outs. If the same size bits of plaster are in a well vitrified zero absorption clay wall, with no chance for expanding due to moisture absorption, then there is less likelihood of pops. Trouble is the mere act of glazing the bisque is adding moisture to the clay so the pops can occur during the firing. As to whether there will be pops sometime in the future, regardless of if it's cone 04 or 10 or somewhere in between, I would be looking at the absorption of the clay vs the firing cone. Higher the absorption figures would equal a greater chance of lime pops if the plaster bit is large enough to expand to the point of having the strength to blow out the wall if it doesn't happen during the firing. 
    Welcome to the forum.
     
  14. Like
    Min got a reaction from Callie Beller Diesel in Porcelain decorating slip   
    An engobe is going to be harder to fit to bisque clay than a slip going on leatherhard. Slip recipes or claybodies that contains ball clay are not going to be as white as one that doesn't, given the impurities in ball clay. You can add zircopax to compensate for this or use a recipe that doesn't contain ball clay. As for an engobe to use on bisque, have you tried using a white underglaze? 
    Fish Sauce Slip works well for me on wet and leatherhard clay, it's very white as it is but can be made more so by adding up to 10 zircopax. In theory you can use it thinly on bisque too but I've had cracking with it when doing that, none when I used it on wet and leatherhard clay. It can be mixed up thickly to achieve textures if that's something you are interested in also. Bentone MA is expensive, if you need a large amount of slip (to dip pots in) then find the whitest bentonite you can and use double the amount. For brushing amounts I'ld use the Bentone MA.
    I removed the bentonite from the original recipe and replaced it with 1/2 the amount of Bentone MA (aka macaloid) to reduce the specks you get with bentonite.
    Fish Sauce - altered - cone 04 - 10
    43.8 Grolleg 
    15.6 Silica
    23.5 Minspar
    7.8 Pyrophyllite (this is crucial to the recipe)
    4.7 Bentone MA
    0 - 10 zircopax (optional)
    total 95.4 without zircopax 
  15. Like
    Min got a reaction from Roberta12 in Porcelain decorating slip   
    An engobe is going to be harder to fit to bisque clay than a slip going on leatherhard. Slip recipes or claybodies that contains ball clay are not going to be as white as one that doesn't, given the impurities in ball clay. You can add zircopax to compensate for this or use a recipe that doesn't contain ball clay. As for an engobe to use on bisque, have you tried using a white underglaze? 
    Fish Sauce Slip works well for me on wet and leatherhard clay, it's very white as it is but can be made more so by adding up to 10 zircopax. In theory you can use it thinly on bisque too but I've had cracking with it when doing that, none when I used it on wet and leatherhard clay. It can be mixed up thickly to achieve textures if that's something you are interested in also. Bentone MA is expensive, if you need a large amount of slip (to dip pots in) then find the whitest bentonite you can and use double the amount. For brushing amounts I'ld use the Bentone MA.
    I removed the bentonite from the original recipe and replaced it with 1/2 the amount of Bentone MA (aka macaloid) to reduce the specks you get with bentonite.
    Fish Sauce - altered - cone 04 - 10
    43.8 Grolleg 
    15.6 Silica
    23.5 Minspar
    7.8 Pyrophyllite (this is crucial to the recipe)
    4.7 Bentone MA
    0 - 10 zircopax (optional)
    total 95.4 without zircopax 
  16. Like
    Min reacted to Hulk in Recycling/Reusing Clay for Practice   
    Hi Chloe!
    Putting the fines back in can take some time.
    Smooshing your piece(s) when you're done practicing, drying the clay* a bit, then going right back to work with it should work for quite a while.
    Keep your throwing water; let it settle, then pour off the clear part, retaining the settlings (muck!). You might find two or three buckets helpful in managing the muck... Down the road, as the reworked clay gets tired, let it dry out completely**, then slake it with the retained muck and minimal added water to form sludge, thoroughly mix/blend (I use a grout mixer in a big drill motor) until smooth (this can take a few sessions over several days), heap up the wet reclaim on plaster bats, turn and wedge (can take a few days) until ready to work again - bag it!
    Reclaiming takes time and effort! Is it worth it? Not for everyone...
    There are several threads here on reclaiming clay, and many vids out there as well, e.g. https://www.youtube.com/watch?v=4xLiJxSGCwI
    A regular contributor here had suggested adding small amount of "fixit mix" to reclaim - eight parts ball clay, one part silica, one part feldspar, if I remember correctly - doesn't take much to improve over the original (imo); more elastic, slower drying. There's ref in this thread https://community.ceramicartsdaily.org/topic/19047-reclaimed-clay 
     
     
    *drying clay: wedging, per Benzine's suggestion, above. For damper clay, try spreading on a plaster bat or block - the plaster wicks the water out quickly. Wedge and turn periodically until the clay is ready to work - wedge thoroughly!
    **individual preference here . Some prefer to allow trimmings, failed pieces, broken pieces - all but the "muck" - to dry out, then slake it when ready to start a reclaim project. Others keep the entire mass wet.
  17. Like
    Min got a reaction from Babs in Adding depth to encapsulated stains   
    @Babs, I believe the theory on adding a titch of zircopax (less than 3%) is since the zircon doesn't enter the melt it acts as a seeding agent for the bubbles that can be an issue with encapsulated stains. 
  18. Like
    Min got a reaction from Benzine in Rinse greenware before firing??   
    To rinse off bisque ware is a very individual decision, I don't think it's a yes or no decision. How porous the pots are, how thick the walls are, brushing versus dipping versus spraying glaze, specific gravity of the glaze etc. If I rinse my pots off it would be a couple days before they are dry enough to glaze,  for me if I think they need it I just wipe them down with a damp sponge and that's enough. 
  19. Like
    Min reacted to Magnolia Mud Research in Low fire soda ash glaze for Malcom Davis Shino-like effects   
    My suggestion: 
    Take the stiffish (aka: does not run) of your cone 3 glaze and start adding baking soda to the glaze mix and see what happens.  As a starting point start by mixing baking soda in water, with some food coloring to keep track of where on the pot you have made marks, and apply the wash with a brush on bisque war.  take photo to know where to look for the marks after the firing.  That is how Malcom got started in his Shino rabbit hole.   A buff clay body will show the value texture more that a white clay body or porcelain.  
    I recommend baking soda (officially called sodium bicarbonate) because it is available at any grocery store, easy on you hands, dissolves in water, and at about will convert to sodium carbonate in the kiln at about 50 C.  
    If starting with an existing glaze recipe with baking soda added, be prepared that the glaze "might" run off the pot until you have enough data to support a conclusion that the mix does not run of the pot.  
    I start with bowls and only applying "new glaze concoctions with extras" only on the inside.  start with the mental idea that you are doing this to see what happens, that way you will never be disappointed by the results.   
    At any firing temperature above about cone 012 the baking soda (or washing soda, or soda ash) there will be some surface reaction between the clay body and the soda even if that "something" is just a clear glass.  
    LT
  20. Like
    Min got a reaction from Chilly in Dusty bisque firing   
    Going forward I would suggest putting some cones in so you can see what the kiln fired to. Just going by time alone isn't accurate enough, for glazes especially. It's good you are having someone look at the plug/wiring before doing another firing.
  21. Like
    Min got a reaction from dAO in Rinse greenware before firing??   
    To rinse off bisque ware is a very individual decision, I don't think it's a yes or no decision. How porous the pots are, how thick the walls are, brushing versus dipping versus spraying glaze, specific gravity of the glaze etc. If I rinse my pots off it would be a couple days before they are dry enough to glaze,  for me if I think they need it I just wipe them down with a damp sponge and that's enough. 
  22. Like
    Min got a reaction from Roberta12 in Rinse greenware before firing??   
    To rinse off bisque ware is a very individual decision, I don't think it's a yes or no decision. How porous the pots are, how thick the walls are, brushing versus dipping versus spraying glaze, specific gravity of the glaze etc. If I rinse my pots off it would be a couple days before they are dry enough to glaze,  for me if I think they need it I just wipe them down with a damp sponge and that's enough. 
  23. Like
    Min reacted to Benzine in How to Move Heavy Greenware   
    Almost anytime, that myself or my students have made something large, I had them build it on a kiln shelf, or something else, that can just go in the kiln with it. 
    That gave us something strong to grab on to, while we were moving them. 
    As others have stated, showing us some reference photos, would allow everyone here to better help  with the problem. 
  24. Like
    Min got a reaction from Callie Beller Diesel in Dusty bisque firing   
    Going forward I would suggest putting some cones in so you can see what the kiln fired to. Just going by time alone isn't accurate enough, for glazes especially. It's good you are having someone look at the plug/wiring before doing another firing.
  25. Like
    Min reacted to Callie Beller Diesel in Dusty bisque firing   
    That’s normal, and it’s not your kiln. Some clays will do this more than others, and I seem to recall the earthenware I worked with waaay back in the day also seemed chalkier than usual after the bisque. Just give everything a rinse and let it dry before glazing. The dust isn’t good for you, and it’ll keep your glazes from applying properly. 

    edited to add: not all clays will require this: some only need a wipe off with a damp sponge. Some don’t need it at all. Go with your own observations. 
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