Bruce Beasley: Acrylic Casting
In the late 1960’s I began to have
dreams of transparent sculpture. I was fascinated by the idea
of sculpture that you could see into and through. Sculpture where
you saw the front and backside at the same time. What would be
the esthetic problems of a transparent medium?
Research into glass and plastics quickly revealed
that both glass and polyester resin (the traditional casting resin
sold in hobby shops) are not sufficiently transparent at the thickness
I wanted to cast. Further research led me to the conclusion that
only polymethyl methacrylate, the acrylic plastic better known
by the trade names Lucite and Plexiglas possessed the absolute
transparency that I wanted.
Acrylic is one of the oldest plastics and in some
ways it is still one of the most remarkable because of its outdoor
durability and exceptional transparency. With these characteristics
acrylic was the perfect material for the sculpture I wanted to
cast, with one drawback. No one, including the manufacturers Rohm
& Haas or Dupont or the military, had succeeded in casting
thick sections without having it crack and fill with massive amounts
of bubbles.
Casting acrylic is just the opposite of casting
bronze. Instead of starting with a solid material and using heat
to make it liquid, you begin with a liquid and use heat to turn
it solid. The problems are twofold. The first problem is that
acrylic shrinks significantly when it polymerizes (polymerization
is the term for turning from the liquid to the solid state). The
shrinkage not only distorts the shape, but it causes massive voids
in the center of the casting. This happens because the outside
of the casting polymerizes first and as the outside hardens and
shrinks it pulls material from the center, thereby causing shrink
voids.
These shrink voids appear to be bubbles, but they
are actually small voids that have a vacuum in them. The second
problem is that the polymerization or hardening itself is highly
exothermic, meaning it gives off a great deal of heat. This causes
a runaway reaction where the heat given off by the initial stages
of polymerizing causes too many other molecules to polymerize
too fast and the heat generated is enough to boil or even set
on fire the acrylic that is still liquid.
I experimented for most of a year and was able to
get to the point where I could cast acrylic up to six inches thick.
This was encouraging but was far from the thickness needed for
the sculptures I wanted to make. However, this size of casting
allowed me to see enough to know that transparency had rich and
exciting esthetic possibilities.
Just at this time when I had learned to cast moderately
sized acrylic sculptures, I was chosen to compete for the first
public artwork for the State of California. I was a young sculptor
only twenty eight years old and this was a great honor and an
important opportunity for a young artist. The state competition
created a huge dilemma for me because I had been selected to compete
in the competition based on my previous work in cast metal. My
heart was in the ideas I had for transparency, but I did not know
if I could learn to cast acrylic in really large sizes. I screwed
up my courage, or you might say that I was foolhardy, and I entered
and won the competition. I entered a model in cast acrylic not
knowing know to cast the large sculpture that I would have to
make and that I had confidently told the jury that I knew how
to do.
With a lot of added motivation, I continued to do
experiments in the direction that I had been pursuing, but I made
little or no further progress in being able to cast thicker. It
was as though the material was telling me that DuPont was right
and that acrylic simply could not be cast in massive thickness.
I did not know what direction to pursue next and I began to fear
that I had been foolishly over-confidant and that I would be a
failure at my first opportunity to do a large public sculpture.
I decided to approach the problem in a different
way and to try to feel what happened to the material over the
entire process. This allowed me to understand what was happening
more completely than analyzing step by step what I thought were
the critical elements. It sounds trite, but the understanding
of what was happening, and therefore the solution, came to me
in a flash. The next experiment produced a casting three times
thicker than I had done previously, and I knew then that I could
cast any thickness.
The casting of the big sculpture for the state capitol
was successful. It is titled Apolymon and it is 15 feet wide,
nine feet high and four feet thick.
Casting acrylic requires that the curing takes place
under high pressure in a rather sophisticated and expensive device
called an autoclave. It is basically a high-pressure oven. Since
the entire casting has to cure inside, you need an autoclave with
an interior space as large as your largest casting. The critical
variables are catalyst, time, heat and pressure. The curing cycle
increases as the casting gets thicker. Apolymon was in the autoclave
for three weeks and during that time I did not know if the casting
was successful or not. I timed the opening of the autoclave to
correspond to the first moon landing – I wanted to benefit
from any extra good luck there might be floating around.
Metal and Wood: 1980-1986
In 1980 I began a series of maple constructions
and larger welded metal sculptures. The metal pieces were a development
of a 40-foot welded steel sculpture I made at the Oregon International
Sculpture Symposium in 1974. I was interested in doing larger
sculptures than were possible in acrylic. I also wanted to be
able to do some of the same shapes smaller, and I decided to do
them in maple.
Using the computer: 1987
In 1987 I was struggling with trying to make sculptures
using complex intersections of simple box-like shapes. I was interested
in the often-surprising new shapes that result from the intersections
of simpler shapes. What interested me was to start with a vocabulary
of shapes that alone were boring and did not evoke human emotions
and to see if by combining these shapes I could make new shapes
and arrangements that did. This idea is analogous to musical composition.
The composer does not invent any new notes. It is the arrangement
of the notes to each other that makes the difference between banality
and beauty.
I wanted to approach shape the same way. To achieve
this I was struggling with building cardboard models from compositions
I was constructing in my head. I could build two and sometimes
three intersecting blocks, but past that I simply could not visualize
the results of the intersecting blocks. If I couldn’t visualize
it, then I couldn’t build it. Even the few cardboard models
that I made presented a problem of scale-up because the models
were not accurate enough to serve as patterns for larger pieces,
and it would be a nightmare to do the same sort of fitting and
trimming with large plates of metal.
Just at this time I was invited to be one of nine
sculptors from the US and Europe to each make a big steel sculpture
in a large and very sophisticated machinery-manufacturing factory
in Germany. I sent off one of my cardboard models hoping that
this company that made some of the most sophisticated machinery
in the world would figure out a clever way to build my sculpture.
They started making the sculpture before I was scheduled to arrive,
and when I got there the piece looked absolutely terrific. All
the planes fitted perfectly and the edges and intersections were
precise and sharp.
I thought to myself, “great, they have figured
out a smart way to generate patterns to cut the plates of steel”.
It turned out that they had made the sculpture by the very labor-intensive
technique of making a full-size sculpture in wood pattern stock,
doing all the fitting and trimming in wood, and then using that
piece to measure and cut the steel plates. It made a wonderful
sculpture, but it was too labor intensive a technique to use myself.
If I made them that way, I would only be able to make one sculpture
a year. However, the symposium did give me the opportunity to
see a large and superbly crafted sculpture in the new shapes that
I was struggling with. I returned home determined to find a more
efficient and spontaneous technique so that I could make sculptures
using this kind of arrangement of intersecting shapes.
I am not an artist who sees a finished sculpture
in my head before making it. I am not sure that any artists do,
but I don’t. I also do not find drawing in two dimensions
allows me to work out three-dimensional ideas. I always found
myself turning the drawing over to see what was on the other side.
For me, the final sculpture is the result of an exploration of
shape as I make the sculpture. Therefore what I needed was a way
to spontaneously experiment with intersecting shapes without getting
bogged down in the drudgery of cutting and fitting just to see
if I liked a particular arrangement. What I needed was a three-dimensional
drawing pad.
I guessed that the solution would be the use of
computers and I began an investigation into three-dimensional
computer modeling. 3D-computer modeling was in its infancy in
the late 80’s, but it did exist. One of the first really
robust 3D computer modelers is the program “UG” made
by Unigraphic Solutions Co. They became interested in my use of
their program to make sculpture, and were of enormous assistance
in adapting the program for my needs and use.
UG is unusual in its ability to be customized to
the user’s particular needs. This is a very important characteristic,
and makes UG quite unique. A full-blown 3D modeling program like
UG is quite complex to learn and at that time, UG did not run
on personal computers and required a workstation level of computer
that was more expensive and complicated than today’s robust
personal computers. I was able to use UG at one of the science
labs at UC Berkeley enough to convince me that it was worth the
investment of time and money to set up my own computer lab. With
a lot of help from Hewlett Packard, I installed a HP UNIX workstation
running UG software. The combination of the HP hardware and UG
software has proved to be outstanding.
Some people have the misconception that the computer
is involved in the esthetic decisions of making the sculpture.
Nothing could be farther from the truth. What the computer does
is to allow me to experiment and play with many different compositions
of shapes in a spontaneous way. I am free from the distractions
of cutting, fitting gluing, and supporting a real model. It is
truly a 3-dimensional drawing pad where I have the ease and spontaneity
of drawing but I am drawing in a 3- dimensional world where I
can walk around the sculpture as I am drawing it. I find working
this way to be very liberating. I feel very free to try many possibilities
and experiment because no real material has been used yet. When
I change my mind I throw away electrons instead of bronze.
Once I have a composition that I like, I have to
bring it into the real world and make it in materials that have
weight and substance. The bronze castings are done in the traditional
lost wax process except that for each casting I make the sculpture
in foam core, which is then burnt out just as wax would be. The
larger bronze sculptures are welded from bronze plate that has
been carefully cut from patterns. Accuracy is very important because
if there are errors in fitting the shapes then the sculpture simply
will not go together.
Bruce Beasley
February 2001
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