Sand and Media Blasting

What Is Sand Blasting?

Sand blasting is also known as abrasive or media blasting, which is a surface finishing process that often uses a powered machine - typically an air compressor as well as a sand blasting machine - to spray abrasive particles under high pressure against a surface. The term “Sand”blasting is used because the common material that is used as an abrasive is particles of sand - similar to beach sand or play sand you would find in a sand box. As the sand particles strike the material surface they remove any old finish or corrosion as well as provide a smoother texture. When you see the term “media”blasting, this refers to other types of abrasive materials that can be used such as crushed walnuts, glass beads, and a wide variety of other materials depending on the surface that needs to be treated and the finish that is desired.

How Does Sandblasting Work?

Sandblasting uses the abrasive properties of sand to create smoother surfaces with fewer physical imperfections and flaws. Sand is rough and gritty and because of these properties, it’s able to wear away at excess or unwanted material on a surface. If you think of how rubbing sandpaper on material’s surface will remove some top-layer material, creating a smoother texture. Sand blasting works the same way except it involves using highly pressurized sand.

How Is Sandblasting Performed?

We use two different types of sand (or media) blasting applications. We have an internal cabinet that is powered by our house air compressor which uses a green diamond media at pressures up to 120 PSI. This is used for applications that are physically smaller - from car rims and down or that require a much finer or detailed final surface finish. For larger projects such as furniture, automobile frames and the like, we use a high pressure 180 PSI diesel compressor and an external sandblaster which mixes the sand with either straight air or water can be added to the mix to control dust and provide a finer finish.

In either application, sand or media is blasted across the surface of the material and because of its abrasive properties, the sand is able to create a smoother surface and will remove any old finish or corrosion.

Is Sand Blasting Necessary?

Depending on the project, sandblasting might be the fastest way to prepare a surface for finishing such as powder coating. If you look at a car frame, for example, that is loaded with rust. To sit there with a wire wheel or brush can take a very long time to remove all rust and get it down to bare metal. The final surface will also be loaded with scratches from the wire and may require sanding depending on the desired surface finish. Sand blasting will two both jobs at the same time - blast off the rust and provide a smooth even surface finish and the process will take much less time.

As a rule of thumb we sandblast most “refinish” work before we powder coat. So if something was previously finished or has a layer of corrosion then we will sand blast to prepare the surface for coating. If parts are new from steel or aluminum, then most often they can simply be treated and prepped with degreaser and other chemicals and then move right to powder coating without the need to sand blast.