March 1, 2008

Making a Jar

Here are the tools on my bench...


Centering...

Next, I open the bottom with a ball opener/bottom maker.

Here I open the bottom of the pot with ball opener in my left hand and sponge in my right hand. I forgot to take off my geeky wireless headphones for the photo shoot!?!#

Now time for a good yank...
I am measuring the bottom section to match it to the previously thrown cap. I usually throw the cap ever so slightly smaller than the bottom section.
Here I am adding the "cap" that I actually made before I threw the bottom section. I measured the cap before I took it off the wheel with my calipers, then set it aside. The cap is slightly smaller than the bottom section. One advantage to capping is that the clay is still wet and can still be stretched and thrown. The other advantage is that the torque in the clay, or the throwing lines are in the same direction in both sections.


The two sections are "welded" together. With my left(inside) hand I move at the same time as the right(outside) and in the opposite direction.

Then I make the opposite move with the weld. This "cancels out" the marks so that when the pot is turned you don't get caught in the ruts of any makes you have made.

The section is ribbed and thrown.

After the sections are thrown together and consistent, the rim is measure for the next cap.

A new cap is thrown. The cap has no bottom and the ball opener rides on the wheel head.
Measuring the cap. Throw the cap wider at the base then you think you may need. Its always easier to narrow than widen. When I cut the cap off, and set aside I always make the table wet so the cap doesn't stick to the table when I need to lift and put into place later.

The cap is set in place. I really don't score the sections, but I make sure that the section below is scraped of slurry.

The second cap is thrown into place and the rim is set.

The whole pot is actually ribbed and thrown into shape. At some pot I rib from the inside only , but I find that the "line" of the pot looks stronger if you can thrown the shape in rather than just ribbing it. I didn't photo graph my stand that I have to get up on while doing these final reaches for the bottom. Also either roll your sleeves up or wear a cut off shirt and mind your apron. These can snag your pot and ruin it.

Here we see our geeky potter hamming it up after the work is done. Handles will go on the jar in the morning. Any questions?

6 comments:

  1. Thank you for that!
    How fantastic to see that making a large pot is so easy. ;)
    I enjoy your blog, keep writing please.

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  2. Thank You "anonymous". It's as simple as 1, 2, 3,... 4,5,6, 7......8, 9...
    Just get a lot of clay and away we go! Go to it! Just make sure you can fit it in your kiln.
    Thanks for reading.
    Michael

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  3. So how much clay do you use for the main part and the two additions? I've tried the way Nic Collins does it, by adding doughnuts of clay, but never this way.

    And how thick are the walls of you pot at the end of throwing and when you add the two sections - are they equal thickness or is the section slightly thicker?

    Sorry... you did ask for questions...

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  4. I was hoping someone would ask. The bottom section was 9 lbs, the "middle cap" was 5, and the "top cap" was 4. 18lbs all together. Gallonage was generally calculated 5 lbs per gallon, although a gallon pot is usually made with 6lbs. Please see Terry Zug's seminal 1987 study of North Carolina folk pottery, "Turners and Burners".

    Sorry that I left that detail out. Also, I cut and wedge the whole amount to blend the clay evenly. If there are "any" lumps or inconsistencies in dryness/wetness it will make your work difficult and the clay wall uneven. It's always hard to guage how thick the clay wall is or report to you but I would guess that it is 1/4 to 3/8ths thick.

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  5. do you ever get cracking on that seam? when i connect stacked forms, i use the "male/female" connection. problem i have with that is the thickness is always a pain to smooth out. oh, and are any of these sections drying out between assembly?

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  6. I used to use that groove thing, but didn't like that bump in the clay wall. I haven't had any cracking with the cap technique. The thing is, I do a pull or two before it gets stretched out too much. I also think the "weld" helps to seal the joint. The sections are pretty wet when they go together. I found that when I would leave the sections out to dry, they would dry unevenly sometimes. That puts a twist in the pot that was hard to get rid of. But you would be surprised what a few minutes can do for your sections, especially in the winter with the heat on in a dry studio. I sometimes use a big torch to set the bottom section a bit. But there again if you're not careful it you can over heat the clay. The shape of the pot is really important to get the right structure. If you look at the pictures, there's not a whole lot of curve to the pot till all the sections are joined. Hope that helps. I'll be looking for some 5 gallon pots from your kiln soon, Kyle.

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