Work Processes

The question I am asked most often about my glass art is “how do you do that?” While there is no simple answer that covers all of my work, or even a small sampling of my work, this section of my website is an attempt to broadly answer that question by giving an outline of the steps that are usually followed in bringing a work to completion.

This description of the processes I use to develop and produce my glass art is never completed exactly as depicted here. It does not account for or anticipate the flashes of invention, serendipitous accidents, and beneficent mistakes that are unanticipated but often occur. Because of the time required from conception to completion of a piece, a number of pieces are in progress, though at different stages of development, at any given time. So these steps are often overlapping.

Ideas

The ideas for my glass art come largely from contemporary culture, as well as from mythology and religion, persistent themes in history and art history, philosophical ponderings, and the usual, oddly disjointed notions. The ideas are triggered by eclectic reading, current events, and assorted private conversations.

These ideas are filtered through my own experiences, training, education, and ethos. Those that remain after this filtering and festering, or which recur often enough to become inveterate, are taken to the next stage of making them narrative and visual.

Drawing and Drafting

Once an idea has captured my attention, and I can visualize it or its implications, I begin drawing. The drawings include sketches of the overall appearance of the piece, as well as individual figures and details of the figures, and a general layout for the fused enamel paintings on the sheet glass. General color choices are made at this time, though the subtleties of the colors, particularly for the painting on sheet glass and the patination coloring of cast, electroplated or electroformed metallic elements are usually modified as the piece progresses.

The dimensions of the sheet glass are determined at this stage, as are the mode of display and details of the mechanical fastenings. The hardware to be used in the assembly of the piece is visible, and so its color, texture, positioning, and mechanical effectiveness are integrated into the piece at this stage. The mechanical fastenings and metallic elements, just as the painted sheet glass, will be a part of the narrative context and overall experience of the glass figures. Templates for the sheet glass are also constructed at this time for use in its fabrication.

The drawings are not considered as a rigid blueprints for the piece, but the effort involved in taking an idea from this stage to completion is sufficiently great that I try to anticipate and resolve as many problems as possible while still working only with pen, pencil, brushes, and paper. This stage may take from several weeks to several months to complete. Many ideas must be held in this stage until I develop new techniques or arrive at alternative ways to solve the technical and artistic problems that this stage exposes.

Glass Sheet

The plate glass is made to my specifications or in accordance with templates that I provide to a commercial glass fabricator. This includes the edge finishing or polishing and the placement of the bevel or radius of the chamfer. Proper cutting and finishing of plate glass is almost an art unto itself, and locating a good technician willing to work (and rework) to provide the exact results I desire has been a frustrating process. The fabrication also results in significant wastage of heavy plate glass sheets, so it is somewhat expensive.

Before the plate glass is painted, I drill the holes to be used later for mounting the hardware and attaching the figures. This is carefully done with hollow core diamond bits in a high-speed motor on a positioning jig so that the holes are placed exactly where they are intended. Experience has taught me that this must be done before the glass is painted because the firing or fusing of the enamels disrupts the surface annealing (applied during glass manufacture to improve the flexural strength) of the plate glass, which can result in spalling of the glass around the hole. Drilling before painting and fusing does not guarantee that spalling will not happen, but it avoids having to discard a glass sheet in which many days or weeks of work have already been invested.

Glass

The clear and colored glass for my figures is made from Soda-Lime glass that I manufacture. It is simply made from fusing sand, alkali, and carbonate fluxes, in the proper proportions, in my gas-fired pot furnace.

The molten pot glass must be drawn into rods for later use at the torch. Colored rods are produced by making color overlays of the crystal before it is drawn into a rod. By controlling the thickness of the overlay I am able to control the color intensity and opacity of the rods.

Some of the glass that I use is supplied in exquisite colors by Richard Ritter in the form of large, heavy rods. These are pulled into thinner rods for use in the torch by heating plugs in the glory hole and drawing them in the usual manner. This glass from Ritter has a different coefficient of thermal expansion than the glass that I make, so it cannot be used with the glasses that I manufacture. The figures can be made solely from one glass source or the other.

Figures

I decided early in my career in glass that I preferred to work with soda-lime (soft) glass, rather than boro-silicate glass because of the wider array of colors available and the greater color vibrancy of the soft glass. This decision imposed a number of challenges, which range from the need for preheating the glass in an oven before it goes into the flame, through the need for very exacting annealing processes following each time the figure is placed in the flame. Soda-lime glass has a lower melt viscosity, and is extremely sensitive to exact matches of the coefficient of thermal expansion of the colored and clear glasses fused in making a figure. These restrictions are offset by the higher surface tension of molten soda-lime glass and the shallow temperature / viscosity curve of the molten material. These physical properties make working with soda-lime glass a challenge because it is less forgiving and places a higher demand on the techniques used to manipulate it into figures.

The glass rods that will be used in making the figures in a session at the torch are selected and placed in a torch-side, computer controlled annealing oven and slowly brought up to a temperature that will allow them to be brought to the torch flame without shattering from thermal shock. The tail ends of the rods extend out of the oven so that they can be handled, similar to the use of a punti for manipulating blown glass.

The techniques that I have developed for making figures rely largely on the manipulation of the molten glass in the torch flame by taking advantage of its surface tension, viscosity, and elasticity. This requires torches that are capable of providing a wide range of flame sizes and thermal outputs. My torches are fueled by Propane and compressed Oxygen gas.

As each piece is finished in the flame it is returned to the hot annealing oven. At the end of a working session the oven is programmed to very slowly bring the day’s completed work back down to room temperature. This controlled preheating before flameworking, and controlled annealing after flameworking is absolutely critical for any completed or partially completed piece in which different color glasses are fused.

Metal Casting

The suggestive elements for combination with the glass figures may be structurally quite large. When this is the case, the element is laboriously made out of wax, and then a high temperature refractory material is formed about the wax construct. This mold is then filled with molten metal, displacing the wax, in a ‘lost wax’ casting process. When cooled, the mold is broken and the casting removed for final finishing. Because metal casting equipment is not compatible with a glass studio, I have the molten metal part of the process done by a local commercial foundry.

The most tedious part of making the metal castings is the extensive finishing handwork needed to give the casting the appropriate surface and minute contours. I do this with hand grinders, files and abrasive wheels, as well as air blasting with abrasives.

To date I have only done pieces with cast bronze or cast aluminum. Iron or steel is a possibility that was discounted because it has no advantages over bronze and is limited in the surface colors that can be obtained by patination. Because of their weight, bronze castings are not suitable for wall-hanging pieces. All of the bronze castings are designed for freestanding pieces.

Patination

The patination process imparts color to the metal by reacting it with various chemicals, including oxidizing or reducing agents. The patina is attained by applying the chemicals to the surface of the metal and then accelerating the reaction by (very carefully) applying heat directly from a flame. An example of the range of colors available from patination of copper is seen in A Cynic’s Quartet.

Aluminum is not susceptible to the same patination process, and I was disappointed with the narrow range of colors and lack of color texture when I tried anodizing.

Glass Painting

The glass plates of the pieces are painted to provide a context or setting for the figures. The painting and drawing is done with paints in which either very finely ground colored glass or fusible metal oxides are the pigment. When later heated, the temporary binder is pyrolyzed or volatilized away, leaving the pure pigment on the plate glass surface. Continued heating to above the flow temperature of the pigment fuses it to a glass so that it becomes integral to the planar surface, much like flash glass. Since this temperature is at or near the flow temperature of the glass plate, care must be taken that the plate is not distorted in this process. Depending on the composition of the pigment in the paint, the resulting glass screed will be opaque, translucent, or clear color.

The glass paints are prepared by finely mixing the pigment with a volatile binder oil. After each color is applied, the plate is placed in a large, computer controlled bed kiln and slowly brought up to the fusion temperature of the pigment. After slowly being brought back to room temperature, further painting or overlaying of paints is done.

In the case of clear or translucent colored enamels, colors beyond the range of the pure pigments is possible by overlaying sheets of fused glass enamels. The colors of the over-laid glasses are additive. Experiments and experience has shown that premixing the pigments, or overlaying the paints before firing leads to muddy or murky colors. So, a firing to fuse the glass before another application is attempted must follow each application of enamels. The colors of the rectangles on the back sheet of The Taming: Kiss Me show the effect of additive color overlays and the overlay of paint gradients.

Mechanical Assembly

Part of the beauty of glass is the interplay of light on and through the medium. To preserve this quality in pieces that are designed to be wall hangings, the pieces are held out from the wall so that light may enter from the back of the piece by reflection from the wall. Spacers that are integral to the mechanical assembly of the piece and the hanging hardware provide this offset from the wall.

For those pieces that have a front and back glass pane, the assembly hardware consists of conventional steel bolts, stainless steel or brass washers and acorn nuts, and enameled or patinated copper sleeve spacers. Because the entire assembly is held in rigid compression, with sheet glass as part of the sandwich, rubber washers are always used wherever glass and metal would come into contact. Plastic flow of the rubber in compression means that the nuts must be re-tightened (finger tight is sufficient) about every three to five years.

Either an acrylic wedge hanger of my design, or jewel-clasp, rigid wire hanger designed and tailor constructed for each panel, are used to hang single pane pieces and the individual panes of multi-pane installations. The visible clasp of the wire hangers are either patinated or polished, depending on the intended visual contribution to the piece. Both of these types of hangers provide an offset from the wall.

Hangers

The hanging hardware for those pieces designed to be wall hangings are of three types, cable, acrylic wedge, and rigid wire.

The cable hardware (plastic coated stainless steel wire cable) allows the piece to be hung in a manner similar to hanging a painting or picture. Because of the offsets that hold the piece away from the wall, there will be a small force on the wall attachment that is perpendicular to the face of the wall. For this reason attachment hardware that mechanically screws into the wall is preferred. Most of the weight of the piece is expressed as a shear force on the wall attachment, similar to a painting.

My design of the acrylic wedge hardware allows the wall attachment to be hidden by the piece, and the acrylic block becomes the upper offset holding the piece out from the wall (see Biography). When properly hung, all of the force acting on the wall attachment is a shearing force. The pieces in acrylic box frames are hung with my design of a variation of the acrylic wedge hardware (see Serious Consideration).

Rigid wire hangers are custom constructed for each panel. Though I have only used this type of hanger for pieces with opaque plate glass panels (enameled or mirrored, or both) they still provide an offset from the wall to allow for the hidden hardware that attaches the bust or caricature to the panel. I designed these hangers to hold the panel by a self-tightening jewelry clasp mechanism. This type of hanger is used for the panesl of Schemers, Innocents, and Pawns.

The hanging of my pieces of glass art is part of the art and intention of the piece, though variations are possible. Therefore, I include with each piece detailed directions on how the pieces are to be hung, with an eye toward making the installation as simple as possible and within the skills and capabilities of most homeowners.

Frames

Unlike freestanding artwork such as sculpture or blown glass, the narrative nature of my pieces and the created context for the narrative gives them a metaphorical frame. This frame can be implied by the edges of the back and front sheets of plate glass, or a more implicit physical frame may be needed to emphasize the narrative intention. The exact nature of the physical frame is dictated by the visual properties of the piece and the intended narrative.

Some pieces, designed without a front sheet, are displayed in an integral acrylic frame. Though these were initially intended as simple fixtures to protect the piece during shipping, they immediately evolved into an integral part of the piece and its design. The pieces of the acrylic frame are contract-machined with a groove to accept the edge of the sheet glass back and the edges are polished. The frame is constructed around the completed piece by solvent-fusing the joints. The frame is designed so that the panel will not touch the wall when the piece is properly hung with the stand-off hardware. The clear acrylic allows light to enter the piece both directly and by reflection off of the wall, and the polished edges channel ambient light to surround the piece. An example is the acrylic frame used for Serious Consideration.

A custom wooden frame, painted to represent age and distress, was also designed and constructed for Temptation of Anthony. This larger piece required a more defined limitation, but the figure is in front of the frame and extends outside of it. Though this piece is a wall hanging, the frame also incorporates the large open-mesh welded wire structure of my most recent freestanding pieces (see below).

I fabricated the frames for the individual panels of Conversations by cutting and laminating very thin layers of beech wood . These were then painted and attached to the panels with an inverted form of the wall-offset wire hangers for the panels.

Large, open-mesh welded steel wire frames were made for a series of freestanding pieces (though they are also amenable to being hung). These frames suggest a partially open book, implying that they are a scene from a story, but the figures and constructs of the piece also extend beyond and through the book cover frame to indicate that the narrative has a larger interpretation than a single incident in an isolated story. These types of frames are common to Storm at Gallilee, Book of Solomon, and Rebecca at the Well.

Photography

Photographing glass art is something of an art itself, and it is one that I have had to learn because of the absence (or my lack of awareness) of local photographers who understood the vagaries and challenges of this esoteric skill. All of the photographs on this site were taken in my photography studio that I designed specifically for photographing my glass artwork.

Though the photography remains highly experimental (trial and error), I have found that the following settings seem to work best, or at least provide reasonable starting points. Using a SLR Nikon Nikkromat EL camera with a 52 mm lens, at f16, fitted with a HOYA Skylight (1B) filter and Kodak Ektachrome 64T film, exposure times of 1/8 to 1/30 seconds are best. At f5.6 exposure times are 1/30 to 1/250 seconds. The (professionally developed) slides are scanned onto my Mac computer with an Epson Perfection 1640SU bed scanner with a transparency adapter and GraphicConverter as the scanner driver software.

I have recently begun experimenting with using a digital camera for the photography, since this would eliminate the expense of film and developing, and the tedium of scanning the slides.