Glass etching is an age-old old method of imprinting images on glass; and one way to do it is by sandblasting. Sandblasting allows for greater variation through the use of different degrees of coarseness in sand, and also for depth blasting, giving the finished product a rich textured appearance.

Sandblasting process

Sandblasting is essentially the process of blasting the surface of glass with grit which peppers the surface, giving it a milky white appearance.

Sandblasting is a general term used to describe the act of propelling very fine bits of material at high-velocity by steam or air to clean or etch a surface. Synthetic particles or small pieces of coconut shell are sometimes used instead of sand in sandblasting applications.

Sandblasting Glass Etching

The sandblasting glass etching process consists of corroding glass by violently projecting sand upon its surface by means of a current of air or steam. The tube conveying the current of air or steam terminates at a nozzle containing a series of fine holes. The sand, is thrown violently against the glass plate or any other body placed within its range, and thus exerts a corroding action. By varying the quantity of the sand, the volume and velocity of the current, as well as the diameter of the jet, the desired effects are obtained.

Bodies much harder than glass have submitted to the action of sand thrown forcibly in this way against their surface, and have been as rapidly worn away. The portions of the glass which are to remain clear are covered with paper, or with an elastic varnish - these substances being sufficiently exempt from the corroding action of the sand.

Sandblasted glass

Sandblasted glass is produced by spraying sand at high velocities over the surface of the glass. This gives the glass a translucent surface, which is usually rougher than that obtained by etching. During sandblasting, only the areas that are to remain transparent are masked for protection. The depth and degree of the translucency of the sand-blasted finishing vary with the force and type of sand used.

The sandblasting technique is used to obscure visibility through glass, but the glass continues to still transmit light as it is diffused through the surface. Patterns and designs can be created using a mask which resists the abrasive force of the grit from the sandblaster. The mask can be hand cut or computer cut depending on the design.

Sand carving is achieved by blasting away the glass for longer periods to get layers of depth. It^s necessary to use thicker pieces of glass for this and the various depths are made by cutting away more of the resist each time. This can sometimes be a long winded process but is desirable for its three-dimensional appearance.

If an image is supplied in a vector format, it can be cut directly using a computer aided cutter. Otherwise, the image in the computer needs to be changed to vector lines the cutter can follow, though this can also be a time consuming process if there is tonality to the image. It is better to supply flat graphic images in this case.

Sandblasters

There are two kinds of sandblasters: “Suction” / “Siphon”" & “Pressure” Blast Systems. Pressure systems are ten times faster & much more effective, but also quite a bit more expensive. There are two basic kinds of sand blasters: Blast Cabinets & Portable Blasters

There is a huge variety of abrasive blast media out there each has its purpose. One you want to stay away from is Silica Sand. Blasting with Silica sand causes Silicosis of the lung. Do Not Ever Use It!

If you are looking to blast hand tools, such as saw blades, wrenches, etc., then sandblast cabinet is better. (A “Suction/Siphon” cabinet would probably be sufficient.)

Sandblast Cabinets must have adequate lighting, a dust collector, and two gloves to place your hands inside to blast within the cabinet. One nice part about blasting inside a cabinet is that all the dust is contained, so no respirator is needed. They are also relatively quiet, and some have abrasive separators which allow you to get the maximum life out of the abrasive blast media & consequently save money.

Application

Dividers, doors and shower surrounds are some of the most popular architectural uses of sandblasted glass. Sand-blasted glass can be used in numerous interior design applications in both residential and commercial settings: doors, shower screens, partitions and interior screens, furniture, etc.

Architectural Uses of Sandblasted Glass

Sandblasting effects on shower doors can create wonderfully frosted looks to compliment the appearance of any bathroom. Typical sandblasted shower surround designs include waves or horizontal lines, but some designs are more ornate such as pictorial sea life scenes.

Sandblasted glass panels on front doors are popular and can really add elegance to the front door of a home. Commercial storefronts and doors may feature sandblasted company logos and business names.

Although glass etching is extremely decorative, sandblasting is not done for aesthetics alone. It can be an attractive and practical solution to reduce the appearance of fingerprints on glass. The frosted appearance and/or different textures sandblasting gives glass can make fingerprints and smudges more difficult to see than if the glass was left as is. Sandblasting glass can also help it repel dirt build-up such as on shopping mall doors and shower enclosures.

Some sandblasted glass room divider panels are more like art pieces than just architectural necessities. For example, some upscale hotels or museum lobbies feature large panels of glass with detailed sandblasted etchings that may include figures or animals. Smaller artistic sandblasted glass panels may be used as architectural accents in homes such as in front halls and kitchen sink backsplashes.

Even small amounts of sandblasted glass can add interest to any residential or commercial outdoor or indoor space. Designs for architectural sandblasting are created on computer software programs. 

Stencils and sandblasting machines are used to transfer the design onto the glass. To create small pieces of etched glass, it^s possible to cover a piece of glass with contact paper and then cut out a design from the paper using a utility knife. Sandblasting equipment can then be used to create a sandblasted effect on the areas not covered by the paper and the contrast between the sandblasted and plain glass is revealed after the remaining paper is peeled off the glass.