Oak faced ply,

[david and julie]

Got a problem with some oak faced ply which I have fitted inside a boat. When I fitted these boards it was very dull outside. Since then and also under a better light, I can see black marks which look like water marks on the surface. The wood yard don't want to know as I have cut the boards to size. The marks are quite deep and will not sand out.

A nearby boater suggested caustic soda may clean them followed by flatting off and oiling or varnishing. As anyone any other suggestions (other than the obvious)

 

[DAZB]

You may get a more informed response on this site..........

http://www.ukworkshop.co.uk/forums/

Good luck.

 

[petewood]

Caustic soda will bleach the veneer so you would need to do the lot to make it look even. Rustins do a product called Wood Bleach specifically designed for this. You would then need to stain the veneer or it will look very pale and not much like oak.

Water-marks will often sand out but I guess if it has been left standing wet for a long time the marks may be too deep. Contact with iron or steel will cause black marks in oak due to a reaction. If this is the case I think it is unlikely that bleaching would hide these marks.

Would it not be possible to stain the veneer darker to try to hide the marks (make sure you use a light-fast stain.)

 

[matz]

Without a shadow of a doubt use Oxalic Acid - they will just dissapear (hopefully)

see here!!! //www.diynot.com/forums/viewtopic.php?t=27621