Is Wet Blasting Any Good?

Wet blasting, also known as Vapor Blasting, has been around since the 1950s. Originally, wet blasting was viewed as an alternative to sand blasting, with its most noticeable advantage being that it reduced airborne dust amounts. It was also observed that wet blasting left a more desirable finish on the part. The use of wet blasting has been growing recently in many industries. Originally receiving the most use in automotive and motorcycle restoration applications, vapor blasting can now be found in the aviation, medical, and production industries. With vapor blasting’s growing number of users, it begs the question: Is wet blasting any good, and if so, what are the cons?

Pros & Advantages:

• As stated earlier, wet blasting keeps down the amount of airborne dust. Due to the addition of water, dust particles become absorbed rather than finding their way into your lungs. This means that vapor blasting can be used in controlled environments where cleanliness is necessary. 

• The addition of water also helps to make your media last longer. In a sandblasting cabinet, the abrasive that is propelled onto the part hits it at full force. In a vapor blast system, the water that is propelled with the abrasive cushions it as it hits the surface. Though this sounds counterintuitive, as you are typically attempting to remove something when wet blasting, the abrasive is actually allowed to do more work. Instead of using the force of the abrasive to clean your part, the abrasive’s characteristics are utilized. For example, when using silicon carbide, the sharp angular edges are allowed to strip the part. In a sandblasting cabinet, they simply pound into the part. 

• With wet blasting, you can clean and prep surfaces at the same time. This means that greasy and contaminated parts can be blasted, cleaning and prepping at the same time. When blasting with clean water, contaminants can be removed off the surface to a point where the part is ready for coating after blasting. This is not achievable in a sandblaster, as typically air and sand alone are not enough. 

• The additions of water also promotes against hard packing. When sandblasting parts with pits or passageways, it is always a headache making sure all the media is removed. In a vapor blast cabinet, the abrasive is suspended in water, which deters the packing nature of abrasive. It is still recommended that you thoroughly rinse and dry your parts, but it is proven their is less media remnants. 

Cons & Disadvantages:

• Lets go ahead and address the largest issue with wet blasting, flash rusting. Depending on the part and its construction, flash rusting can happen immediately. This is not ideal for any part that requires a coating or finish. There are ways to mitigate this issue, with the best solution being corrosion inhibitor. Once added to your machine, and your parts are blasted with its inclusion, there is around a 72 hour window where no corrosion will take place. This is the perfect amount of time to apply a coating after vapor blasting. 

• Wet blasting may be more expensive at start up. As the machines are more complex than traditional sandblasters, with the addition of a slurry pump, plc, and more, as well as requiring sturdier construction, they do tend to cost more. 

To answer the question: Is wet blasting any good?