ssor
08-08-2008, 10:13 AM
This is only remotely related to boats but perhaps a good place for it anyhow. I just finished a ceramic tile foyer and nailed down some red oak mouldings at the edges. I have done this on other jobs with no complication but this time the grout stained the oak like wet iron filings will but very uniformly black. Another job in the same house with the same moulding but a different grout color didn't stain the oak at all.
The cure was simple . I mopped on some oxalic acid and the stain went away. I can only conclude that some of the pigments in the grout were the culprit.
The cure was simple . I mopped on some oxalic acid and the stain went away. I can only conclude that some of the pigments in the grout were the culprit.