Below the waterline.

[OGITD]

Hi all,

Now that the winter maintenance period is upon some of us I was wondering as to the best method of preparing below the waterline prior to antifouling, do we have to resort to a light sanding or will a good power wash suffice? Plus is there any process or product which is best for sealing the hull if this is a known \ recommended sensible requirement?

 

[Pasarell]

2 different questions here.
If your old antifouling is in good condition then you can get away with a pressure wash before recoating. You should pressure wash when it comes out of the water anyway and, if you are leaving until the spring to recoat, wash again before painting.
You need to rub it down if the old antifouling is loose, flaking, or rougher than you would like or has any other defect. Always rub down wet and avoid getting antifouling on your skin as much as possible.

By sealing the hull I assume you mean against osmosis? There are plenty of products available for this but you will need to remove the old antifouling completely first. An antifouling primer will seal off the old antifouling but unless you have doubts about compatibility with what you plan to use I wouldn't bother.

If you are looking for an osmosis prevention scheme then, of course, my product is best! PM me if you would like information.