Jump to content

Callie Beller Diesel

Moderators
  • Posts

    4,415
  • Joined

  • Last visited

About Callie Beller Diesel

  • Birthday 11/14/1976

Contact Methods

  • Website URL
    http://www.dieselclay.com

Profile Information

  • Location
    Alberta, Canada
  • Interests
    Soda fire, all things reduction, and a little bit of glass.

Recent Profile Visitors

21,119 profile views

Callie Beller Diesel's Achievements

Advanced Member

Advanced Member (3/3)

4.7k

Reputation

  1. Hi and welcome! Just to clarify, do you want it to look different in the bucket, or in the end result? If you want it to look different in the bucket, food colouring works a treat, and burns out. If you want the end result to look different, a small quantity of a light blue stain would pop glaze colours better than a brown or grey one would.
  2. So I’m going to preface this by saying I’ve never fired Obvara, and I’ve only ever fired raku by eyeball, never with cones or thermocouple. (Please do this with proper eye protection). So I couldn’t tell you what temperature exactly I was using, but the glaze recipes used were mostly gerstley borate at the time, and that melts between 1550 and 1600 F. So my question is, can you fire the raku pieces to a lower temp to match the Obvara recommendations, or are you using glazes that really don’t mature until that hotter temp? If you do need the hotter temp for raku, it’s possible to roughly judge the temp of a piece by the colour of the glow coming off it. The chart linked below has a nice colour gradient illustration, and you can do a bit of a comparison from there. There’s a paywall, but you can use one of your 3 free articles/month to view it. https://ceramicartsnetwork.org/ceramic-recipes/recipe/Kiln-Firing-Chart-142658
  3. I first got hooked on clay because we did raku at my high school. The only time we had anything explode was the one time we tried firing a piece that wasn’t bisqued first.
  4. I’ve seen this form a bunch, and yeah, it’s tricky to get right. One solution for the warping I saw another potter online do was to do all the minimal trimming and cleanup as you describe, but they then added a slip trailed circle of clay as a foot rim. It was just enough to keep the full surface of the plate’s bottom from being in direct contact with the kiln shelf so you don’t get the warping, but still keeps the same aesthetic qualities of this style. Results may vary with different clay bodies, but it’s something that’s worth a shot.
  5. Hi and welcome! I wish it was under better circumstances. The pictures are worth a thousand words, and thank you so much for including those! The fact that the piece is broken so cleanly, and in 2 near-perfect vertical lines all the way through means that this wasn’t specifically your clay, or anything you did during building the piece. It’s a nice dense clay that probably stuck to the kiln shelf due to the mass and size of the piece, and cracked during cooling. For the next pieces, I’d fire them on some sand/alumina so that the piece has the equivalent of little refractory ball bearings to shift around on. You could also use a waster slab that will shrink at the same rate as the piece, but take the brunt of the force and absorb the crack instead. If the clay survived the bisque just fine, another possibility is to not fire the piece to full clay maturity. Porosity in the end piece is less of a concern for you than it would be for someone throwing functional ware.
  6. Are you sure that’s iron oxide? There’s lots of other possible solubles that turn brown.
  7. While I add dry ingredients directly to my old batch at my personal studio all the time with no ill effects, if you’re in a teaching studio, you might want to mix the new batch separate and test it to verify everything went as expected before adding it to the old batch. And depending on how well the studio members/students are mixing the batches, you might want to let it run out as far as possible before adding new. If incomplete mixing is a habit, it can mess with the glaze.
  8. This one from my students. If you manage to wear the skin off your pinky, vet wrap is a good way to protect it.
  9. If you can’t get proper pottery plaster for a reclaim slab, you can lay an old sheet over wire racking and lay thick slurry out on that to dry.
  10. I used paper clay for a couple of years. It lives up to all that hype! It’s much more forgiving about when you attach pieces, so if you’ve got time constraints, it’s a great material. The 2 main things you want to watch are the stink from cellulose breakdown, and to be mindful that then end piece will be somewhat more friable than the same piece made out of regular clay would be. How much more friable will depend on how much pulp you add. The rot can be managed in a few ways, the easiest being to only mix up what you’ll use in a short time frame. The next easiest is to prepare a larger batch, and dry it out in really thin sheets that can be stored and rehydrated as needed.
  11. If the mixture is homogenous, the shrinkage rates should wind up somewhere in between the 2 different points. You’re making a whole new clay body.
  12. In all the years I had to transport work for firing, I found the best fix was to have small sealable sandwich bags of glazes to do touchups when you got there.
  13. @semidoomed if the glazes are only being fired to cone 04 and cooled in a normal firing, the clay body won’t matter a great deal. If they do want to pull the pieces out of the kiln while hot, it’s a good idea to wedge in a bunch of grog if there isn’t any already to help ease some of the thermal shock.
×
×
  • Create New...

Important Information

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