Wet (vapor) blasting technologies and dry blastingare similar in performance with regards to surface preparation. The shortfalls of older wet blasting technologies have, unfortunately, often been carried over and associated with newer wet blasting products. This misconception has given rise to myths that current wet blasting is not as effective as dry blasting.
Not only is wet abrasive blasting capable of removing the same kinds of contaminants as dry blasting, but it is also compliant with various surface preparation standards such as the SSPC SP10 (NACE No. 2) specification for near white metal cleaning.
Although the two are capable of the same kind of performance, the finished surface produced by dry blast cleaning differs significantly from a surface produced by wet blasting. Because dry blasting relies on the force of the impact to remove old coatings, rust, etc., the blast media can often penetrate and remove pieces of the substrate, resulting in a rough finish.
During wet blasting, the water acts as a cushion that prevents the abrasive particles from becoming embedded in the substrate. Furthermore, the water serves as a lubricant that reduces the heat generated by friction between the particles and the substrate. The result is a more even and polished finish.
For this reason, wet abrasive cleaning is often preferred over dry blasting for cleaning antique, fragile, soft or otherwise sensitive materials. (To learn more about this topic, see Understanding the Industry Shift to Wet Abrasive Blasting.)