Cindy on mon 28 apr 97
Hmm, where was I? Sorry . . . my computer wierded out on me in the
midst of that big pot. Here's the rest of the post.
Okay, so you have a big, solid donut on your bat, approximately the same
diameter as the rim of your base pot. If it's an inch or two smaller
because of the size of the bat, that's okay--you can flare it out. You get
into problems, though, if you try to flare it out too much, so if the bat's
too much too small, you'll have to get a larger bat.
Pull up a *thick* wall. You're going to turn this thing upside down, and,
holding on by the bat, place it on top of your base pot. Measure the top
rim of your ring/pot section, and when you've got it equal (measure from
center of the wall on one side to the center of the wall on the other
side), place a groove in it using your wooden rib (v). A carpenter or
machinist would call this the female part of the joint. The ^ on the rim of
the base pot is the male part. That analogy should give you a pretty good
idea of how they fit together.
Clean up the bat in the middle of your section ring (use a rubber rib, and
a sponge), then scrape away the excess clay near the inside wall of the
section. Using a sharpened stick, undercut the wall so that the clay is
partially cut away from the bat. Undercut on the outside of the ring as
well. Take care that you do not completely sever the ring from the bat,
Re-check the measurements to make sure your section will fit perfectly on
top of the base pot, then lift the bat from the wheel and take it to the
base pot. Turn upside down (you'll need some help with this if you're
making a real whopper) and fit it carefully on top of the base pot. When it
is placed perfectly, spin the wheel at a fairly slow rate and, using your
needle tool, cut the section from the bat (which is now sitting on top of
your pot like a lid), lift the bat off, and place it aside.
Smooth the joint between the base and the first section by "throwing
downward". Start just above the joint and, with the wheel spinning at a
comfortable rate, move your fingers downward over the joint, thus sealing
the sections together. You may get bubbles in the joint. You can pop them
later--for now, unless they're really troublesome, just ignore them.
Once the sections are joined, you can complete the throwing of the new
section of the pot. Pull it up until it matches the thickness of the
base--or you may want it just a bit thinner. Slow down and dry the pot a
little if it ever seems too soft. It is important to note that, as the
circumference of your pot increases, it will take longer for your fingers
to compress a complete circuit of the walls. You will find it necessary to
pull upward v-e-r-y slowly. Have the wheel moving perhaps a wee bit faster
than you feel comfortable with. You don't want it too fast, of course, but
the natural tendency for me was to have it moving too slowly.
You can continue on like this as long as your wheel can handle the weight
and you can physically open the clay for the new sections. I found it
pretty difficult on occasion to pull the walls of that donut outward. (No
problem centering the clay, as I did it in sections.) While you are pulling
outward, you have to remember to also keep downward pressure on the clay.
Otherwise, you'll pull it right off the bat. When refining the walls, be
sure to pay close attention to creating a smooth, continuous curve without
bumps or dips. That's a large part of the difference between a big, ugly
pot, and a $45,000 pot.
When you're ready to stop, give your pot a substantial rim. Add a section
and pull it up very little. Shape this section into a lovely, thick rim. A
thick rim will help the pot to keep its shape and will also improve its
appearance, IMO. All the large pots I made were well-compressed, and done
on plaster bats, so cracks in the bottom weren't a major issue. If you have
your base on a non-pourous bat, I suppose you'll have to devise some way of
cutting it off once the pot is finished. On the plaster, they just seem to
dry off without problems. At least, that was my experience with the four
pots I made at the workshop.
As for firing them, well, that's "easy". You just have to build a kiln big
enough. If you try this, let me know how it goes. Also, you might consider
getting Jepson's video on making big pots. I haven't seen it, but his
personal instruction was a great help to me. And I hope this helps you. :)