On Thu, 19 Mar 2009 12:34:37 GMT, (Bob Masta) wrote:

Thanks Bob! I did the project today and did a lot of what you suggested. We
used a heavy tissue paper over the cups and I had pre-cut 'windsheilds' of clay.
It was easy to get a pattern by rolling the cup on a slab, cutting out the
result, checking the fit and then tracing it on paper. The kids worked as
partners with one holding the cup steady while the other wrapped the clay around
it. They switched roles, then added the bottom, made with a biscuit cutter. The
cup slid right off and they worked the inside and the rim. I was happy with how
well they did! I like the idea of the toothbrush and tarpaper - may use it
next time so we don't have to collect so many cups ;-) Best, Sue


To get the clay off of the outside of the yogurt
containers quickly, try wrapping the container
with a layer of old newspaper first. You might
want to make a template and pre-cut a bunch of
sheets for this. Wrap the paper on the container
and tape it to itself... no tape on the container.
Then the clay and paper will slip off together
after forming. (As long as you don't wait so long
that the paper is saturated.)

Another tip is to use "tarpaper" (roofing felt) to
make templates of the mugs. This is sold in big
rolls at building supply stores. Get the 15#
stuff (30# may be too stiff). Your template will
end up being 2 pieces: A disk for the bottom of
the mug and a curvey piece like a windshield for
the body (plus a handle piece, if you want.) Use
plain paper to make the master template, and
expect a few trial runs until you get it the shape
and size you want, then cut the working
template(s) from the tarpaper.

These templates will be for the *outside* of the
piece. Roll out a slab between sticks the
thickness you want the mug walls to be, wet the
template pieces, roll them into the slab to get
them to stick, then use a blunt pin tool or even a
butter knife to cut out the clay+template pieces.
The tarpaper is stiff enough to make a guide, so
the kids can do this themselves (assuming you
trust them with the cutting tool... butterknives
may be better than pin tools for that aspect!).

Now you can pick up the tarpaper+clay pieces and
assemble them onto the yogurt containers. Note
that since the templates are outside the clay,
which is probably a 1/4 inch thick slab (or
whatever you like), they must be enough bigger
than the container that the *inside* will fit.
That's why you might need some trial and error
designing the templates.

But as it happens, you may not even need the
containers as a mold, since the tarpaper+clay is
pretty much self-supporting for this small size...
I have done this without using a container or
other form, and all it means is that you spend a
moment making the circumference round after
joining, instead of whatever oval it just happened
to come out as... you can use this as an
opportunity for creative expression!

Use a toothbrush dipped in water to roughen and
wet the seams before joining. Join the
semi-cylindrical wall portion of the mug first,
then wet and roughen the bottom and join that.
You can leave the tarpaper forms on for as long as
it takes for things to stiffen up a bit, since
they are on the outside. (They are waterproof,
though, so you need to remove them for complete
drying.)

Tarpaper templates can be washed and stored for
re-use. They last a long time. And you can make
all kinds of shapes. A nice simple project I once
did with my young nephew was a butter dish. It's
made from simple rectangular shapes you can lay
out on graph paper to make the master template,
without much trial and error stuff. And the
pieces are small, so they are easy to handle with
the clay attached. I made the lid as one folded
piece... a long rectangle with "ears" for the
sides. When you fold this up, you first score
some V-shaped grooves at the joints and roughen
and moisten as usual, then fold and press. The
tarpaper on the outside holds everything together,
and if you don't make the V grooves too deep there
will be enough clay on the corners to give a nice
rounded appearance.

Best regards,


Bob Masta

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