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Steel boat hull prep

I am contemplating having the old bottom coatings removed by a slurry blasting outfit who has demonstrated that their water and crushed glass media blasting process does a fine job of leaving a clean, bright, roughened surface on my steel tugboat hull. Is there anything I can apply to the hull during or immediately after the wet blasting to inhibit flash rusting that will likely occur before I can begin applying my epoxy primers?

Bob Welters
boat owner - Seattle, Washington, USA
October 30, 2011

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November 10, 2011

I would use any of various phosphoric acid solutions. I think there used to be some that could be cut with water.
One brand I use leaves behind a rough, hard debris because it is not diluted and the liquid clings and forms a kind of crust that has to be removed later. I think one diluted a bit would wet the surface and let the excess run off. You might even come back the next day and put on more where it looks like you missed just to get everywhere. It makes a good base for an 2 part epoxy primer.
Tim

Tim Bandy
- Orlando, Florida, USA