Jump to content

Michael D

  • Posts

  • Joined

  • Last visited

Everything posted by Michael D

  1. Bill, what do you mean by "score the edgeline"? Do you mean seal the plaster on the edges? Please elaborate. Thank you! Michael
  2. Thanks Jeff. I do hammer it in lightly with a mallet. How much would it put me back for a little RAM press set up (or any hydraulic set up) that could make tiles up to 5 or 6 inches? --Mike
  3. Thanks Bill. I am not sure I understand what you mean. Are you saying that I will probably need to make another air-release mold and to densly pack the air tubing in the middle area? I tried a non-stick spray out of desperation and it seems to release much better. But it also left the top a little greasy. And I am not sure what this would do to the pores of the plaster over time....
  4. I went back and tried to sand away any under cuts I don't think it is that as I put a small pug in the middle where there are no real hard edges and with the air pressure it still did not pop out. I am thinking that it has something to do with the clay turning into a kind of mud and forming water adhesion, suction, that the small air bubble aren't overcoming. I tried to dry it off a bit and apply slightly drier clay (which is harder to push into the design). But it actually released better -- haltingly-- after about 8 seconds. But look at the clay film that it leaves behind on the ceramic mold. This suggests to me that something is wrong with adhesion to the ceramical for some reason. Any thoughts?
  5. I just might use the mold release that Mark recommends. But I still will want to know what I have done wrong for the air release not to work properly. I don't see any drastic undercuts. The Ceramical should be fresh enough. Just ordered it about a month ago from the ceramic shop. And the little air bubbles seem to be working. But it just partly comes out and gets hung up in the mold. These things should be dropping after 5 seconds of pressure. I have wondered if it was TOO wet and was forming a kind of slip with the clay I put in the mold, and thus clinging to the plaster surface.... see video.
  6. Mark: The Tiler has been discontinued. The manual and instructions only say to keep it moist. I've tried all kinds of variations of wet and moist. The tile just doesn't pop out as it should. The brown clay seems to want to cling to the plaster too much. I tried wet sanding the plaster to give it less texture but that doesn't seem to have helped one bit. Can the mold lube be used with an air-release? Without clogging the capillaries? thanks Md
  7. Hi, I poured my first air-release mold (to use with a Texas Tiler). The mold is very erratic in whether or not it releases the tile as it should. The tile just stays in there. I tried various things. I filed down and sanded angles to help remove any undercuts. That didn't work really. I sanded the surfaces with wet sandpaper to make it smoother. I even tried a little soap with little improvement. Any tips? Wetter or dryer clay? Non-stick spray? (will it clog the air pores?) I use about 60 to 70 psi. The mold is made from ceramical. (spelling?). It bubbles a lot from the surface so I know air is making its way. Please. please. please, any advice from experience! --- Michael
  8. I have some "ware repair" and some other products designed for repairing greenware and bisqued pieces. If, though, I have a finished stoneware mug that has broken, is there a way to fix it permanently with some product that will readhere the pieces in a second firing? Any tricks of the trade? I used a Loctite product and it didn't hold up very well. thanks Michael
  9. I never thought of oxygen needing to flood the surfaces of the tiles. If in the future I grooved the bottoms of the tiles this might make a big difference as it would allow much more oxygen and sulfates to come and go..... Right now it is just the texture from canvas, probably not enough. Thanks!
  10. Hi, I make small tiles in my ConeArt kiln, Cone 6. For economic reasons I have been stacking the tiles horizontally, sometimes several of them-- with not problems for the bisque firing. They seem to be bisqueing fine. My question is: so long as the tiles are dry, and that the kiln has sufficient power, is there any reason why I shouldn't stack the tiles much higher, say 5 or 6 inches high? Especially if I leave an inch or so space around each stack? Thanks Michael
  11. Stephen. Do you ever come to a conclusion about Hydrocal vs Cermical? And the best rubber for the model? thanks Michael
  12. Yes. you are looking at the underside of the shelf just above (no more than 1" above) the tiles with the glaze that copper and other ingredients I listed. I hadn't noticed this before and these are new Corelites. The glaze has no more than 2% cu in it. Maybe a chemical reaction with the new shelves... Thanks
  13. I’m curious why, above and around certain tiles, in closely stacked shelves, there is a clear brown halo. The glaze in question has among other things, strontium, lithium and copper carb in it. It’s clearly coming from just that glaze. Any knowledge on this and if this should be a health concern? (I run a venting fan during the firing.) thanks.
  14. Thanks Min! I read somewhere that the B2O3 (or boron) should be at least .14 for Cone 6. But you say that I may have too much alumina in the recipe for this. Is Silica easier to melt than the alumina? Is that why you suggest I get more flux (or boron) in the recipe?
  15. Hello all: as I examine the specs on glazy, trying to make sure I have enough boron for a proper melt (trying to get at least .15, it’s not clear what these numbers mean (circled in pics). It looks like I am fine with R2O. But it’s the boron numbers that confuse me. How should I see/interpret these numbers? mike
  16. I'm blown away by your generosity of sharing knowledge and time. Thanks to all! I feel like I just too a crash course in glaze chemistry, etc. I see now that the original recipe may look cook, but it is clearly an underfired gloss that may not be stable. I've am seeing now how vital it is to have an understanding of the various tools: stull, R2O ratio, glass to alumina ratio, cooling rate.... And after that it is really about testing and verifying in my particular kiln, with my particular firing schedule. I'm still trying to figure out the R2O/RO ratio as that seems really tricky and contingent on various things. And I am thinking that this measure has a lot to do with durability, say in a washing machine, and may have less meaning on tile, or art. Thanks again. I have lots of ideas to run a few more tests. Md
  17. Thanks Callie and Bille. That was an enlightening video, Bill. Thanks! I do a drop and soak, Cone 6 and the witness cone says that it fired nearly a full C6; (I have other C6 recipes in there that were gloss, and they turned out great.) Maybe it is a problem of slow cooling (many shelves with tiles). But again, the other tiles came out great. After watching this video, I think it's clear that I need more flux. or frit. Here is another question: I have no idea when looking at the Stull chart, and R2O, what the cone for the recipe should be. This helpful video says that Boron should be .18 for a Cone6 firing. But I don't see on Glazy where to read that level. And if that is the best way to assess what Cone the glaze is made for. Do you know a way to look at the date supplied on Glazy and assess the proper Cone? thanks! Michael
  18. Hi. I'm pretty much a beginner with Glazy. When I enter a recipe for a very matte white into the Glazy recipe maker, it shows on the UMF chart and the Stull chart that it should be high gloss. I know it is matte because "matte" was the recipe of the original recipe and because it has made very matte glazes from my kiln. I wanted to experiment with entering into the calculator more frit, or more glass to make the glaze less matte and more semi-matte, but this is throwing me off. Could it be that this C-6 is really just an underfired gloss? That maybe I just need to add a little more frit to make it a little more satin? Thanks for any advice!
  19. Thanks for all of your advice! It sounds like 1" Corelites would be fine; And maybe even the 5/8" . If they warp after 50 firings, for example, maybe I could flip them or just replace them. And maybe I could strategically move the posts in a little-- say two inches toward center -- and give the shelf more support that way. Right now, if I place the shelves I have (which are modified 11x22"-- there is a good inch in there for clearance and fingers. I was originally going to use setters but because I am experimenting with different and small tile shapes it didn't add up. I figure that with thin and light shelves I could fit maybe 11 levels or more into the kiln for Cone 6. But having only filled it about 1/2 way each firing, I am seeing that the energy to heat up the tiles and especially the shelves is going to be enormous. (Not to mention how long I have to wait for it to cool down....)
  20. Hello Ceramics Friends! I'm starting a small business that involves making smaller handmade tiles. I bought a really nice ConeArt 27" square kiln and had hoped to stuff it full with shelves on 1 inch posts, maxmizing the number of shelves per fire. I'm only a half year into this and it is clear to me that investing in alumina shelves (3/4"") was not wise as it seems like half my electricity is spent in heating them up (and a half day longer waiting for them to cool down). I would love to buy a kiln full of advancer shelves-- the weight, the thinness-- but I just can't afford that right now. So I am looking seriously at the Corelites. I plan to have two rectangles instead of a full square, wet-sawed down to about 11"x 22". I have two questions: Is it ok to get the 5/8 thickness? I need as many shelves as possible, and will only be holding small tiles on them (covering over 90%). Do any of you forsee any problems with going this thin? (I almost always fire to Cone 6). I've read warnings about having a ramp more than 200f increase per hour. My favorite schedule calls for double this. Can any of you share your experience and knowledge? Will it matter to fire a ramp at, say. 300f/hour? I really think these are going to work better for me. I hope I'm right. Thanks in advance for your advice! Michael
  21. I know that overfiring clay, say a terracota to C6, can cause the body to bloat, etc. But besides burning out colors, or perhaps creating a mismatch with a body intended for midfire, is there any fundamental problem with firing a lowfire glaze way beyond its intended cone? thanks Michael
  22. Also, (sorry to hijack this thread). My daughter made her first mugs (dark clay) and wanted to gift them to friends back at college. She is leaving soon and I don't want to rush it and ruin them. But I also need to have them finished by this weekend. If I fire a clear glaze on them and the glaze comes our with too many bubbles (making it opaque), is all lost? Can I fire it again and, say, soak longer, to clear the bubbles? I'm planning on brushing on the glaze very thinly this time. And slow firing it to C6 with a soak at the peak, and short soak coming down. Michael
  23. Thanks Neil! Will do. I also think that I was hasty in mixing my first test glazes, not sieving enough, and brushing them on too thickly, The glazes all looked great on a white body, but on the dark 710 (which I love) they look horrible. (Which makes me think it has something to do with escaping gases from the body) Michael
  24. Hi Bill: This matte looks great. I am a neophyte in this. Just trying to get a strong, stable workhorse or two base glazes. Cone 5 or 6. I ran my first tests and too many of them came out a little opaque, mostly from bubbles and pinholing, especially on dark clay bodies (710 in particular). I think I may have over cooked them (peak soak time too long, maybe an hour); did not let them slake long enough; but mostly that I brushed them on too thickly. I also plan to drop and soak (drop peak 100 degrees and let it soak there) as a way to reduce bubbling. My question is where are you getting that awesome software, chart stuff? Where it will tell you where your mixture lies in a spectrum from matte to gloss, and help you see the chemical content so well? thanks Michael
  25. Hello All, I love that bowl you made, Harley DP. Anyone have any experience finding a clear glaze that works on the 710 without pinholing and blistering? I ran a bunch of test tiles, C6, and none of my clear glazes came out well. Maybe I have to apply then paper thin to remove the blistering... Please, any advice.
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.