Don't worry about rust from the steel wool especially on a flat piece of plywood, even if it has been shaped into a boat. If a piece of steel wool gets stuck somewhere, it will vanish when you sand the boat prior to encapsulating everything in epoxy.

Scrub pads are nice for scratching up the surface when a light sanding is required. But to get that mildew off you are going to need some cutting power, that fine (00)steel wool will give you.

Jason

: No steel wool please. Some may break off and sticks in the wood. These little
: pieces may be too small to see but may become very apparent when they
: start to rust after repeat soaking and air drying