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  2. Since the clay is getting water logged after firing to cone 10 and according to Clay Planet that porcelain should have an absorption of <1% (from the description of the pugged version of that clay), I would conclude the absorption is much higher than what is posted. There wasn't enough flux added to the mix. I would measure the absorption yourself then contact Clay Planet with your result plus the batch number and hear what they have to say. I would hold off on trying to get a glaze to fit until you have the body itself sorted out.
  3. Thank you all so much for the suggestions. Hulk, I'd post pictures, but would have to spend days tidying up my work space first. Oh, the horror! I think you might be spot on about it being a vision issue. I take my bifocals off for close work and use headband magnifier glasses, which generally means I need to get REALLY close to the piece to see the wee little details clearly. I'm going to try all of your ideas and probably a combination of them and report back in case it helps someone else with a similar problem in the future. The devil sure is in the details for me.
  4. Hm, interesting thought, but I don't think that's the problem. They don't provide instructions but I deflocculate based on measured viscosity and specific gravity, not just a fixed recipe, so I have a pretty well-controlled process. Plus I bisque everything so all the casting water should be long gone. I guess maybe the particles could be too far apart or something? No idea if that's possible. Maybe I'll mix some up some tests without deflocculant until it's just wet enough to wedge and roll out to see if that makes it better. > Not sure, just a shot in the dark For sure, it's a strange problem to have with a commercial clay.
  5. I don't slipcast but do they give mixing instructions for the slip? I'm thinking if it's not properly deflocculated and too watery this might happen? Not sure, just a shot in the dark
  6. Hi all! I just started firing on my own after a while at the local community centre. I'm doing some slipcast cups as a first experiment using Clay Planet's dry Glacia porcelain. However, I've put two test glaze loads through the kiln and the results have been pretty disappointing. The clay feels unvitrified. The texture is closer to bisque than finished ware, and it seems to soak up water slightly. All of the glazes I tried crazed in the bottoms of the cups. Leaving water in one of the crazed cups overnight, I can see it creeping up inside the glaze, soaking the porcelain. This seems pretty odd to me. The first firing was a solid ^10 (I used the standard guide/target/guard cones), and the work is very thin, <2 mm, so it shouldn't take long to come up to temperature. The second firing I added a soak for 30 minutes, and ^11 drooped significantly, but the clay feels the same. A loose piece of broken bisque I set the cones on also broke very easily. The 3 glazes I used were Tony Hansen/Digitalfire's G1947U, the transparent used at the community centre, and a modified version of that sourcing CaO from Wollastonite instead of Whiting. I've never had trouble with the community centre transparent fitting the pugged Glacia I use there, and G1947U should be even lower expansion, but all crazed. For the second firing, I tried to correct the glazes, but even super low expansion borderline unmelted glazes performed very badly. All in all, I'm having very bad luck with the dry glacia. Here is where the questions start: 1) Has anyone seen this before, especially with this clay? Any high-level ideas for what I could be doing wrong? I don't really want to brute force it by just firing super hot/long, especially because I made it well into ^10. 2) Is it worth trying to fix the Glacia, probably by adding feldspar? I have tons of bisque, slip, and dry clay of the Glacia left, so this is somewhat attractive. It would be a bit of a pain though and I would probably have to throw out the bisque. 3) I'm kinda soured on this whole deal, so maybe it's worth just switching clays? The options are probably dry Clay Planet Pier or pugged Laguna Miller 550. I kinda want to avoid another Clay Planet formulation after the Glacia issues, but I also don't want to make slip out of the pugged Miller. 4) Maybe I should just formulate my own porcelain? On one hand, I'm pretty comfortable with the chemistry, mixing, and testing. On the other hand, it would be nice to finish some work and not just test things forever. Thanks everyone for reading and any advice will be greatly appreciated.
  7. Interesting my understanding of reduction contains a mild background in chemistry so I really focus on copper, iron and tin mostly and to a lesser extent cobalt, nickel ...... my view of reduction is that of reducing the oxides which entails char, not necessarily soot or carbon trapping. ............ might be reduction though. let me look at some Raku recipes and see how and what they surface reduce. I am guessing copper but just a guess. cool thing to work out, none the less!
  8. I am naturally dizzy, sorry! Use the string and weight, you will figure it out. Took a lot of effort just to get those up there
  9. Absolutely fair point but how is this any different than copper raku reduction effects, ultimately? Daly's work with nitrate/copper lusters seems fairly well described but its certainly possible Im misunderstanding the physics/chemistry at the end of the day. The porcelain mix suggestions are intriguing but way outside my comfort zone... that said I'll look for a vendor, definitely.
  10. Mousey: search clay makers and find a porcelain body with pyrophyllte. Grog is a widely misunderstood additive.
  11. I guess I would say I am not entirely convinced the predominate effect is reduction?
  12. Have you tried mixing your own porcelain to make it more shock resistant? I'm thinking of spodumene here, perhaps you could tinker with that aspect instead of the firing aspect?
  13. Certainly viable suggestions, and thank you for them of course, but I think I'd like to understand conclusively why this isnt working as is.. so many possible variables. Celadons come out great btw so perhaps reduction isnt the issue core issue? I'd love to find out that this is simply a matter of technique and finesse and perhaps I'm blowing out the glazes and making the metals volatilize before the actual melt.. this is a possibility I suppose..
  14. Could you fime the wares on the cool down-or reduce like I do every fire? Maybe cover the grog body with porcealin slip for that look
  15. So.. bit of background... fell in love with Beato's lusters early on and then discovered Greg Daly's book (and work) and decided to see what I could accomplish with a reduction bucket. This is a porcelain body covered with what is essentially a very melty shino recipe with some nitrate salts added. Fired to about ^06 then placed into the reduction chamber directly from the kiln, and Bobs your uncle. And I'm super happy with how it came out, except that the body cracked. As most of my porcelain pieces handled thusly do (and why shouldnt they; thermal shock, etc). Sometimes I use a nice raku/sculptural body that is groggy enough to survive this sort of behavior but I have two significant complaints; 1) I love porcelain more and 2) the groggy clays tend to gather carbon on all the exposed, unglazed surfaces, especially the parts that directly touch the combustable medium. Its an interesting enough look and sometimes even desirable but if you look at Greg Daly's work, its porcelain and clearly he obtains an appropriate level of reduction within his kiln to create the luster effect without actually inducing reduction through burning organics, eg paper, leaves, sawdust so on (aka what Beato used to do in her electric). I've seen footage of him placing pieces in his kiln and later removing them that back up this assumption; they go into a firing chamber unfired and come out with lustered surfaces. That, in essence, is my desired end game.
  16. This might help as a picture is worth a thousand words. So in addition to the edge that the fluid has to pour over or trailing edge being sharp and not rounded, the tilt of the spout can help. So if we use Neil’s pitcher (thanks Neil), notice the forward lean of the spout. Kind of counterintuitive but we know gravity always pulls things straight down, so a tilting picture of a pitcher is in order. The yellow line is the default spout angle and the red arrow is the pull of gravity. As the pitcher is poured gravity can help pull the liquid away from the dribble zone as long as the spout has this counterintuitive tilt. Add a sharp trailing edge and voila easier job for gravity. Now depending on the shape and size, time to experiment with a piece of string with a weight on it. Just figure the amount of tilt for typical fill level and ya got an easy visual. Also can help determine what is the best angle to block sand your bisque product based on visualized fill levels and your handy gravity indicator (weighted string) hope that sparks some thought! Now as to laminar flow, Reynolds numbers, etc.... for another day. Let’s just say Smooth flow terminates much more cleanly than turbulent flow. Smooth, gentle with reasonable velocity , basically good, rough turbulent basically bad.
  17. ryleigh, once you start using your pacifica, you might never want to use one of those noisy brent things. hope you enjoy it for many years.
  18. welcome out into the light, lurker! i used to make fish about the size of my hand. in shaping them, i used my right thumb to press the body of the fish into the palm of my left hand. did this for years until the hands started to cramp up and tell me to stop it. so i understand now that supporting the work in order to do things to it is very important at all stages. today, i cut a piece of 2 inch thick leftover foam into a hollow curve to hold the pot whose interior i wanted to spray with glaze. now i can direct the spray into the bowl without it bouncing back into my facemask. i think you might try something similar to hold your pieces. since they are small, i would try cutting thinner foam into circles that can be stacked to hold a particular piece today and a different one tomorrow. you probably work in similar sizes most of the time so a stack of cut circular voids can help get the work steady so you can place it conveniently and comfortably in a good position for carving. supporting bigger work might involve stuffing tubesocks and shaping them as needed.
  19. Check out laptop tables, they are adjustable height so you can change it up when you need to. I use one for my laptop but have used it for drawing as well.
  20. "...worry about ...the... types that retire and have no plans other than to do what they feel like." Yep onna that'n!
  21. Congratulations!!!! Who is to say what is fine art? If it brings you joy and delight when looking at it........
  22. Hi Dianen! Would you be willing to post pics of you working at your wheel and at detail? At a table 'bout halfway between bellybutton an' sternum might allow for elbows to rest, an' the workpiece elevated such that just above the wrists can also rest on what the work is on? Perhaps another scenario to consider, where you're leaning back in your workchair, against the backrest - an' arms can then use the chair's armrests - where work is elevated above your lap by an adjustable shelf of some kind, swing-away attached to the chair, or on rollers, or... I imagine the work has to be close enough to get in the sweet spot o' your bifocals (heehee, if'n y'old as meee), for sure such that your elbows are well bent past 90 (inna strong position for rotation of the hand) - hence, close in?
  23. My favorite activities during my BFA ceramics years (long ago) were the hands-on making of clay bodies and glazes. I remember naught now (minor brain damage), but I was quite good at it and being in the studio with great instructors and serious co-students/clay artists turned me on to a life-nurturing process when I was on the verge of quitting "big time". I remember one graduate student who was working in a style similar to Jun Kaneko (this was in the early '80s) and seeing her up on the ladder over this enormous form--it took up the entire gas kiln, set sideways--was such an inspiration, it literally helped me to stay put. So in terms of wishing to have had more training in a particular ceramic skill, I have to say I wish I had more longevity with being able to practice and perform the basics, and then on to the more advanced, more creative, more chemistry-rooted aspects of making clay and glazes. I'd wanna become glazenerd!!
  24. You won't get Raku/sawdust effects by adjusting the burners. They are not the same process. You can put a mostly sealed saggar with combustibles inside your gas kiln, though. Do not seal off your burners and try to fire the kiln. You'll damage the burners from the heat. Sealed burners typically have ceramic tips that act as a buffer between the heat of the kiln and the metal burner pipe.
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