Thursday, June 11, 2009

Glazing

What is the mystery to good glazing. It is all just good guess work?
We are glazing this week and when I say week- it takes of most of a week to wax, glaze and load our big gas kiln.
While doing this I always find we are guessing about the glazes. How did this work last time, do we need to mix and add more, did it run too much was it just right, where did it sit in the kiln?
All of these questions are valuable in how the pot will turn out.
We have enough pottery going in the kiln that we know some will be good and some will be "not so good."
We try very hard not to make seconds, but as we all know......... there has to be a few dogs.
Mark has worked on the formulas to weight each glaze as it worked for the last firing. He has written down the weights on all the buckets. Maybe this will give us a better place to start.
I always have this moment early in the glaze cycle about each pot, how it will be glazed and where it will sit in the kiln. Is this a low shelf or a top shelf, middle stack, front or back stack. If I throw in this 10 inch shelf will the stack run hotter in the back or in the front. The middle is always hot- so choke it down a bit with some short shelves..........
You would think after 26 years we would have this down.
With our firing times off so much from catch up this past year I have lost the rhythm of glazing.
I can see that I need to get it back or take up sewing.
And if you know me you know I can sew but I don't really like it.
So back to glazing today, taking notes and keeping our fingers crossed that we do not melt the glaze off the pots onto the shelves!

9 comments:

Gary Rith Pottery Blog said...

Those are some gorgeous pots there.
I fire a smallish electric kiln, as many as 2 or 3 glaze firings a week, and I still forget which glaze has which peculiarity. Maybe I should make a little chart about the glazing table...

jimgottuso said...

i think we all do that to a certain extent... the problem for me seems to be that when i'm done firing, it seems so obvious what i did and how i did it but then a couple months later it seems to have faded away because of all the other things that have happened since. i guess the only answer is to take meticulous notes but it's not in my nature.

cynthia said...

Take up sewing...HAHAHAHA - that's what I've decided to do. Only partially joking.

I hate that firing pottery sometimes produces duds - let alone the stuff that can happen during making. I guess it makes the successful firings even sweeter though. It's a hard gig. I'm not sure the general public really appreciates all the years of learning that goes into producing a handmade mug or bowl or.....

My ceramic's mentor keeps meticulous notes and encouraged me to do the same. I do keep kiln logs, but I've been lax in the glazing department. I do keep a log while glaze testing, but I haven't done any testing since last summer.

teehee - the word verification thingie is reading "suckbol"

Linda Starr said...

I think the notes are the thing to do, but I really hate writing stuff down - I don't mind typing, but my computer is in the house and the pots are in the studio. If only I had a computer I could speak into and it would transcribe the words and print them out for me - that would be the ticket - I'll bet the technology is there - just not affordable. Where to put the pieces in the kiln is a whole other ball of wax which I will have to learn for my little electric kiln. There needs to be a kiln with a seeing eye - when the glaze starts to run too much - the heat to that section is dampered down automatically. I know I'm a dreamer. Still in all I think there is also a feel for working with the clay and glazes and no matter how many notes are written, there is that unexpected event - either spectacular or lousy that happens no matter what you plan. The cruets and jar are wonderful I love the speckles and the two colors together.

MH said...

The weight I'm recording is slop pint weight or more accurately - slop litre. This may actually be specific gravity since metrics are a sane base 10. Anyone out there have experience with this??

T.Gray said...

Meredith,
I use a hydrometer, a piece of paper with numbers on it, enclosed inside a glass tube weighted with lead. My thinnest glazes, fake ash specifically, measures around 46, and thickest glazes have been as high as 60. My mamo (high alumina matte) is dead on 50.

Patricia Griffin said...

I can sooooo relate to your post. My sister does art quilts and I often find myself thinking... "Well, that certainly has no surprise to it. What fun is that!?" (That's on the good days. On the bad days, I'm saying to myself, "Wow, wouldn't it be nice to know in advance how something is going to turn out?!")

Michael Mahan said...

I had two buckets of glaze with ash as an ingredient (just a bit of glaze in each one). I mixed them together and like the result.

Now, to figure out how to make it again....

Meridith:
Are Will and I playing music from 2 until 4 June 20? During the booksigning, right?

cookingwithgas said...

Well glazing is done and on to loading- but it seems we all have moments with the glaze and TG maybe we need to talk- you seem to have you glazes down.
I would rather make pots then glaze, maybe that is my problem....
Linda- I like how you are thinking- I want an eye on or in my kiln!
And Cynthia I have a feeling that no matter what you do it will come out well. I wish I liked sewing!
And PG- somedays it is nice to not be surprised. I wish I could get the same thing again- then again maybe that is why we do this never really knowing how things will come out.