One half-cup of corn
starch (and maybe a little more)
one half-cup boiling
water
double boiler
stove (hot plate)
flat pan or cookie
sheet
Procedure
Mix the sand and
cornstarch thoroughly in the top of the double boiler.
Pour in the boling water
and mix well (but carefully - its hot!)
cook in the double boiler
briefly until the mixture has thickened. Should it be too thick,
add a little boiling water.
Wait a moment for cooling
and the clay is ready for modeling.
Take out the clay and
flatten it gently with your hands (imagine you are making a thick
pizza) - you can even use a rolling pin.
Using some tool the size
of your playing stones, copy the board grid and the groove around
the board by pressing into the clay.
When the board is finished put it on
a flat pan or cookie sheet in a 275 F (132.2 C) oven until dry. It can be
dried without the oven but it will take longer.