Tip
#2. Attaching Clay Parts.
Case 1: Wet parts. The first thing you learn in ceramics is
"score and slip." To attach 2 wet pieces of clay, you
score both sides with a needle tool or fork, apply water or slip, and
mush them together. However, some potters, even famous ones!, have
abandoned the traditional score and slip method, saying they found
direct contact to be more reliable. When using the direct contact
method, it helps to have a binder. Vinegar works great for
this, almost like a glue. Try it both ways and compare!
Case 2: Dry parts. In general, you cannot attach two pieces of clay
which have dried past the leather hard stage. However, there are
some exceptions.
a) You can sometimes use a commercial mender such
as Magic mender or APTII mender to attach pieces of
greenware or even bisque.
http://www.bigceramicstore.com/supplies/OtherThrowingHandbuilding
We
have detailed instructions for using APTII at http://www.bigceramicstore.com/information/APTII_instructions.htm
.
b) You can make your own potion. Lana Wilson, author of Ceramics:
Shape and Surface, Handouts for Potters, uses this recipe called Magic
Potion which she says is a super duper greenware fixer!!! The
recipe is: I gallon water, 3 tablespoons liquid sodium silicate, 1 and
1/2 teaspoons of soda ash. *Liquid sodium silicate is also called
egg keep and is sometimes available at
drugstores.
c) Paper Clay is a mixture of clay and paper fibers. Using it you can
attach wet and dry pieces, and they will not crack. There are
several excellent books on Paper Clay. You can make it
yourself by wedging blended paper pulp into clay, or buy it in 25#
pugged bags. Paper Clay is excellent for handbuilding because of
this ability to combine wet and dry pieces.
d) A final technique for encouraging good attachment of wet and dry clay is
to wrap wet newspaper around the completed object, then wrap in plastic.
This causes the moisture levels throughout the piece to even out,
resulting in less cracking. Great for those darned feet that keep
falling off that too dry pot. I recently submitted this to an
extreme test, attaching wet clay to bone dry clay that I had
"forgotten about" over the holidays. Worked great!
copyright 2000, Cindi Anderson, www.bigceramicstore.com