December 2011 Issue
Table of Contents
Where Credit is Due
Mailport: December 2011
Sodablasting & Adhesion
I recently read your article on sodablasting bottom paint off a boat (PS, October 2011) and started researching the possibility of doing it in my neck of the woods. I came across several references to companies that will not guarantee paint adhesion to sodablasted surfaces, and I became a little concerned. Is there any additional information you could include about this? I am considering this process on a 1977 Kelly Peterson 44.
1977 Kelly Peterson 44
Sodium bicarbonate is the media used in sodablasting. It is softer and less abrasive than sandblasting or sandpaper, so the process does not open up the gelcoat during paint removal, according to Chesapeake Soda Clean owner Stacey Stone (www.chesapeakesodaclean.com). With fewer open surface voids—which can trap dust—there are fewer places for paint/soda contaminants to hide and interfere with paint adhesion. Once the paint has been removed from the bottom, the applicator air blasts the surface to remove most of the sodium bicarbonate and paint residue. And before painting, a thorough hull brushing and washing is carried out. Many pros also do a solvent wipe just prior to painting, regardless of whether the hull has been sanded or sodablasted. No matter the stripping method, there’s residue left behind that must be removed.
Another tip to avoid surface contamination (and potential paint adhesion issues): Always take a close look at the equipment used by a sodablaster before signing up for the service. A new or well-maintained compressor is less likely to have worn rings that allow oil to escape with compressed air. These also usually have better water separation capability, which allows for a clean stream of compressed air and sodium bicarbonate to be output, decreasing the likelihood of surface contamination.
Editor’s Note: Since our report, the Bad Dust company has re-organized; Positive Containment Systems is the new name for the company manufacturing Bad Dust boat bottom tenting (860/267-1733 or www.baddust.com).