Armour Etch Glass Etching Cream is not recommended for etching large areas of glass. Generally because it is impossible to simultaneously and evenly coat an entire large area and get perfect results. The area where you begin the application of cream will start to etch immediately upon contact creating a number disparities in the results the larger you go. A few common issues are:
Brush strokes. Brush strokes from the application process can create patterns on the glass that have a broom swept look and will appear in the final etching.
Splotchy areas. Splotchy or milk drop looking areas can happen where the etching cream was applied, but not evenly distributed creating darkened areas with edge lines around them. This is the result of a thicker or longer application than the surrounding area.
Unetched or Hot Spots. Unetched areas and hot spots are the result of interference between the chemical and the glass. Unetched areas happen when either a part of the glass is not reacting to the cream or contact with the cream is being blocked by debris. Hotspots occur when chemical crystals in the etching cream sit too long in a spot on the glass. Etching cream is supposed to be moved around and refreshed on the glass sporadically throughout the process.
Dark white areas. If not handled carefully, etching cream can get onto an area it is not supposed to. Glove transfer is a common cause of this. When glass is etched in the same spot on both sides of the glass, that location becomes a very dark white area that stands out markedly from the surrounding area.
Methods conducive to etching large areas:
Etch Bath. As the name suggests, the piece of glass is submerged into an Etch Bath solution which etches all parts of the glass. This gives the glass a nice, frosted look as shown here on the left of the flawed etching cream example.
Sand Etch. Also know as sand blasting, sand and propellant are used to etch the surface of the glass. When sprayed across the surface of the glass, sand etching can provide an even, opaque look as seen here on the right side of the flawed etching cream example.
If the glass can be made opaque, why can't etching be used for privacy screening? Glass etching breaks down/ damages the surface of the glass so light can't pass through it. This causes the glass to become opaque so we can't clearly see through it. When water or steam comes in contact with the glass, water molecules fill in the etched surface and gives the glass temporary transparency. A privacy film, adhesive vinyl and various frosting paints are a better option. For more on this, see Not For Privacy Screening in our Tips and Techniques section.
Article Posted: 11/02/2022 01:35:29 PM