filing in a river

[Ralph]

Hi Kevin, I'd encourage you to not give up on trying to make the surface smooth. I think whatever you use for water will still show the irregularities of the base surface. Maybe you'll have some success wet sanding with a sanding sponge like this: <!-- m --><a class="postlink" href="http://www.rockler.com/product.cfm?page=5747">http://www.rockler.com/product.cfm?page=5747</a><!-- m --> I've bought them at Menards and have used them to sand my joint compound roads.

Best wishes!
Ralph