Saw your question on the Orchid Digest #194. I have done some
pitch work (it’s really my favorite process, I own six pitch
bowls). Anyway, the best pitch I have found is the stuff sold by
Gesswein. I studied under Joe Girtner( the greatest).
The Gertner method If you are starting with
a standard pitch bowl, the 5" in diameter, cast iron variety.
Melt into the bowl enough automotive wheel weights to be about
one inch from the bowl rim. Over a low fire with a metal pot,
melt one and a half pounds of “BURGUNDY” pitch that you broke
into small chunks. STIR< STIR<STIR. When the hot pitch is fluid,
stir in a paper-cup full (16 ounces) of plaster of Paris.
STIR>STIR> and STIR some more. When thoroughly mixed, cut in a
tablespoon of lard and STIR some more.
The amount of pitch prepared exceeds the amount of pitch needed
to fill the bowl so here is the plan.
Be sure the deep sink you filled with cold water before you
started all of this is still full of water.
Did I tell you to tape some heavy foil around the edge of the
pitch bowl? About 1 1/2 inches will do. Oil the inside that is
to come in contact with the pitch.
I hope you are being very careful all this time.
Pour the HOT pitch into the bowl so it is higher than the rim and
kept in place by the aluminum foil.
Put the whole mess into the cold water in the sink. The pitch
will start to wander around and want to run off the crest.
Since you can now mold it under the water, keep shaping the
pitch until it solidifies, maybe up to 10 minutes of continuous
forming. When the pitch is SOLID remove, dry and peel of the
greasy aluminum foil. The finished unit should look like a
bowling ball, a full sphere, half iron, half pitch.
“Good” pitch will keep this shape and not flow off the bowl. This
is a Japanese style pitch bowl. To use it, heat the pitch with a
Black and Decker Heat gun, about $20.00 and guaranteed for two
years When the pitch is hot, attach the work piece and have a go.
I only use torch to remove the repousse piece from the pitch if
it hasn’t already sprung loose during the hammer work. I also use
the torch to burn the stuck-on pitch to a white ash then anneal.
The pickle is not affected by the burnt pitch ash. In using the
torch to remove the work piece, a small, very sharp flame
is played on one corner of the silver an the flame is allowed to
heat the entire piece so it can be lifted off without disturbing
the underlying shape in the pitch.
The above describes a medium pitch bowl. The books will describe
redoing the pitch in summer and again in winter so it is always a
reasonably soft medium. Melting the pitch out of the bowl twice
a year for reformulation got to be a pain in the bowl so I set up
different bowls for different things.
The plaster gives the pitch body, the amount of lard determines
the hardness of the pot. Initial work should be done on a soft
support and final finishing on a relatively hard support. The
soft and a big hammer allows deeper impressions into the work.
Remember that when the metal won’t move or starts to ring,
anneal. Some of my pieces required as many as thirty
annealings.
After your done working you can always reshape the pitch to the
spherical shape for the next time use.
Sorry to be so long winded and jumbled. You touched a favorite
bone. I also make my own tools and hammers too.
Bill
Ginkgo Designs