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Rick Glawson Commemorative Reverse Glass Sign Creation By Larry White Step 1 - Artwork Creation / Step 2 - Glass Surface Alteration / Step 3 - Rendering the Main Copy / Step 4 - Colorizing Center Panel / Step 5 - Gilding Lower Sand Carving / Step 6 - Gilding “Keeper of the Craft” Ring / Step 7 - Gilding Lions / Step 8 - Gilding Glue Chipped Scroll Work and Borders / Step 9 - Gilding Carved Text / Step 10 - Rendering the Secondary Center Panel / Step 11 - Corner Ornaments / Step 12 - Smalt Box Step 2 – Glass Surface Alteration My vision for this piece incorporated various forms
of glass surface alteration. These being; textured acid etching, multi-staged
acid embossing, glue chipping, and sand carving. Alteration of the glass
surface is always done first (but typically after any hole drilling or
edge scalloping). I proceeded to procure a piece of ¼” thick extra-clear
(Starphire) glass XX x XX from a local glass supplier (Western States
Glass, Fremont, CA). Using a mineral light, I determined the float side
of the glass, as this is the side I wished to work on. I will be employing
an asphaltum varnish resist for both the acid etching and glue chipping
processes. I like to set this up using only one coat of asphaltum. This
requires executing the acid etching techniques first, followed by the
sandblasting for glue chipping and the sand carving. The first step is
to clean the glass. I like to just use glass cleaner at this point. I
covered the entire glass with 3 mil Calon II vinyl, then registered and
spray mounted one of the artwork copies over the vinyl. I proceeded to
cut out the areas I wanted to acid etch. I had determined I wanted to
do 2 textures of mica etching and a multi-staged acid embossing. Those
areas are then left on the glass and the entire background weeded (see
photo 1). Photo 1
– Vinyl Mask for Acid Etching and Embossing
The next step is to coat the entire glass with asphaltum varnish. Having been initially taught to apply the asphaltum with a roller, I have found I like brushing it on better. After varnishing, the areas defined for the textured acid etching are carefully weeded.
Photo 2 – Vinyl Weeded for Texture Etching Textured etching is accomplished by mixing diluted hydrofluoric acid into mica flakes. Typically, 2 parts hydrofluoric acid (48-52%) is diluted with 3 parts distilled water (red food coloring is typically added as a safety factor). This is mixed into the mica flakes to form a wet paste. The paste is then applied to the open areas of the glass. I like to use a vinyl squeegee that has been cut in half. The mica flakes settle on the glass and interrupt the action of the acid producing a stippled texture. Mica flakes can be ground to smaller sizes to produce different textures. The different sizes are mixed with the acid in separate containers, but can be applied to the piece at the same time. Here, a fine mica texture is being applied to the “ring”, and a coarser texture is being applied in the center background panel. The mixture is left on the glass for 20-30 minutes. It is scooped back into the container and the residual is rinsed off with water. Be sure to observe all precautions when using hydrofluoric acid. Read and understand the MSDS sheet. Wear all suggested safety gear. Get professional training when ever possible.
Photo 3 – Acid and Mica Mixture Applied to Glass After rinsing and drying, the etched areas are painted over with asphaltum varnish (see photo 4). This preserves them during the acid embossing process. I had chosen to do a multi-staged acid emboss. The “deep” embossed portion was first weeded and after ensuring that all areas had been weeded, the front of the glass was coated with asphaltum varnish to protect it from any action of the acid. The glass was then placed face down in a leveled vat and the same ratio hydrofluoric acid that was used before was poured into the vat. Acid was added until it just came up on the sides of the glass, sufficiently covering the entire underside of the glass. After the acid has been added to the vat, one side of the glass was lifted and re-lowered to ensure any surface bubbles were evacuated. After 20 minutes the glass was carefully removed from the acid vat and rinsed and dried. The fine lines in the lower portion of the main copy were then weeded and then the glass was then returned to the acid vat for another 20 minutes, removed, rinsed and dried. The resulting double emboss treatment resulted in the lines in the lower section of the text being half as deep as the rest of the embossed work. 
Photo 4 – Glass Weeded for Acid Embossing 
Photo 5 – Glass in Acid Vat (Note the red acid solution at the edges of the glass. Also, the reflection in the glass is the filters on the wall of our ventilated work area.) A second application of rubber sandblast mask was applied over the surface of the asphaltum-coated glass. Another one of the reverse copies was registered and spray mounted to the mask. The depth carved ornaments and upper text was cut out and sand carved. The scrollwork for glue chipping was also cut out and sandblasted. The masking was then removed. Photo 6 – Sand carved ornaments and Sandblast for Glue Chip Prepared glue was then flowed into the areas to be chipped. The glue was dried under a fan then placed into a glue-chipping booth. 
Photo 7 – Glue Chipping off of the Glass in the Booth After the glue chipped off the glass, it was removed from the booth and the asphaltum varnish was cleaned off. This completed the first step of glass surface alteration. 
Photo 8 – Completion of Surface Alteration Techniques
Step-by-Step Informational Outline by Larry White / Articles by Rick Glawson / More Articles |
