Powder needs a surface profile in order to properly adhere. If you have ever bought cheaper powder coated fencing at hardware stores, and the powder chips off in strips or sheets, it probably was not properly prepped. Although sandblasting adds more upfront cost, it ensures that the powder properly adheres to the metal, saving you from major problems down the road.
Sandblasting is the most common form of media blasting, you are essentially using compressed air and sand to strip the metals clean and give it the profile the powder needs to stick. If you have ever used sandpaper, it is essentially the same idea. Although sand is the most common, everything from glass, to steel and walnut shells are used for all kinds of different substrates. Everything from wood to glass and plastic can be media blasted, depending on what media you use.
The range of uses for abrasive grit blasting are very broad and include:
- surface preparation prior to painting, bonding or other coating operations.
- removal of rust, scale, sand, or paint from fabricated components.
- roughening of industrial gas turbine engine component surfaces in preparation for thermal spray coating.
- removal of burrs or edge profiling machined components.
- providing a matte cosmetic surface finish on consumer products.
- removal of mold flash from plastic components.
- surface texturing of tooling, and molds to alter the appearance of molded or stamped products.
When we first started, we realized pretty fast that sandblasting to bare metal is the best solution, too many times we ran into situations where the old powder was poorly applied, making the top coat fail just as fast as the bottom coat failed. Especially with projects that are going to be exposed to harsh elements like salt water and snow, you need to be 100% sure that the product is properly prepared and the powder will hold. The quality of the powder coating job is only as good as the preparation that was done before the powder is applied.
With so many different material options, blasting can be done on tons of different substrates. It is very popular for restoring older car parts that have been damaged by rust and time. A form a blasting called soda blasting, using sodium bicarbonate or baking soda to restore and clean objects that are too fragile for media blasting. One of the early examples of soda blasting is in 1980 when it was used to restore the Statue of Liberty. A great benefit to soda blasting is its ability to be mobile, allowing for a vast array of options. Everything from graffiti removal to cleaning boats and satellite dishes.