Wednesday, November 20, 2013

Lazy day guilt

Lord, have I been feeling lazy the past couple of days. Jim says he's happy to see me taking some well deserved rest, so why did I feel guilty for such indulgence! Anyway, I did manage to get the little test kiln loaded, touched up a couple of pots, and finally cleared the slab roller and a did a couple of other studio chores. I found an old flash drive and deleted a lot of files from it and did a bunch more computer filing and cleanup - a good lazy day chore.

My first basil seeds are up so I moved them into my office and have the pot under a grow light now along with the lemon grass plant I brought in for winter. Besides being an office it serves as a plant nursery and meditation room now that we don't have a basement which is where I used to start all my seedlings, nor a fourth bedroom which was a meditation room in the old house.

My black slip tests turned out God awful the other day, so I spent a lot of time yesterday on the computer, checking out other possibilities. Does anyone have a good, true black slip recipe that would work at Cone 04-03 that they are willing to share? Some of the recipes I tried came out grey, not black. The glaze bubbled horribly over another one and only one looked like it might work, but I'll have to make a separate test with that one. I'll have to check that one, but I suspect it may be one with a very high oxide content.

After breakfast I have some late tomatoes to deal with. Enough have ripened, so I think I'll just get them peeled and pureed and make a small pot of  minestrone soup which we can have for lunch. Then I'll head to the studio, and get the last pot slipped, and roll out slabs for the templates I made a couple of days ago. Dinner is leftover pasta carbonara, so I'll be able to work a bit later.

I still haven't received a call about the order I put in for the centering arm so I'm going to have to call him this morning. Right now I have to finish my tea and deconstruct a lovely looking caramel glaze glaze recipe I found on line. It has industrial dust as one of the ingredients, but I have the formula for it, so I'm going to see what I can come up with. The problem may be that Edouard, who posted it, says that this Slater dust has traces of lead, cadmium, nickel and chrome, molybdenum, some of which I wouldn't want to be adding to a glaze.


  1. These are some slips I've had good luck with. You will need to experiment with colorant percentages. I do know that with many black Mason Stains too much will lead to the bubbling you describe.

    Halifax White Slip ^06-03

    Ball Clay..........40
    Neph Sy...........10
    Frit 3124...........5
    Zircopax...........3-5 (may be omitted but will not be as opaque)

    This is the slip Walter Ostrum used on his work when I did a workshop with him many years ago.


    Basic White Slip ^04-2

    Ball Clay........45
    Frit 3124........10


    I also have very good luck using paste as an underglaze. It was developed by someone long ago as way to keep colorants from separating when painting on raw glaze. I usually mix it 50/50 colorant and paste. I mix this by volume and add enough water to make it the consistency of sour cream. When I add color I add more water to get the consistency I want.

    Paste ^06 plus
    1 part Gertley Borate to 1 part Frit 3124

    I sieve this before I use it. A nylon drip coffee filter is fine enough and small enough to sieve small amounts.


    Another option I used when I was working with my developmentally delayed students is Spectrum's Low Fire Underglaze Base #1050. Again you will need to experiment with the amount of colorant to add.

    I use Frit 3124 in everything because it's the principal frit in my glazes. If you use other frits you might want to experiment with using them in your slips instead of 3124.

    I hope this helps you a bit. Don't get too frustrated with failures. Low fire is magical when It works; getting there can be a torturous path.

    Email me if I can be of any help.

  2. Thanks so much for the recipes - so generous of you!. I went over my recent black slips today and a couple of older ones, and the one that seem to be blackest and least troublesome was Ayumi's slip less the zircopax with 15% Mason black stains (6600 and 6650 I think)) So I'm going to make a small bucket of one of those and take it to the next level with a couple of small pots instead of just test tiles. I was hoping to avoid the expensive stains, but it seems that they have given me the best color so far. I've tried Redart bases with oxide additions and either the color isn't right, or I'm getting all gawd awful blistery bubbles. :-(