East coast mud and antifoul

[Oscarpop]

hopefully in about 8 weeks we will leave the east coast and head south to the med.

every other year, we pull the boat from the water, have her jet washed by the yard then spend a couple of three days with orbital sanders taking the brown stain from the hull before re antifouling.

my question is, if you leave the brown stain on, does the anti foul adhere as well?

it takes a sander to get it off and some owners in our yard just anti foul on top of it. another approach would be a light sand to roughen the surface while leaving the stain.

so, can i leave the brown stain and anti foul, or do i need to get it all off to ensure that our anti foul lasts ( micron anti foul)

cheers

 

[Seajet]

I get the same brown stain on my white antifouling - could be said to be a daft colour for a drying soft mud mooring but it does look the best by far, even with the stain visible when she heels.

I just pressure wash the bottom when coming ashore each autumn, leave a day or more to dry then apply two coats of Uno or Micron; the stain covers very easily and the a/f sticks fine, it doesn't make any difference.

 

[Oscarpop]

Many thanks. So long as the brown stain doesn't affect the adhesion of the antique, I've just saved myself a day under the boat. Looks like I will be at the sweeps festival after all

 

[johnalison]

I would be inclined to scour the A/F for a foot or so below the waterline, where much of the fouling occurs.

 

[Seajet]

My boat gets a bit of green weed just above the waterline, especially at the bow where she's weighed down a bit by the mooring, and that can require something like a plastic car ice scraper with lots of water to remove.

However the brown stain Oscarpop mentions is pretty central; even on mud which is dangerously soft to try walking on, she sits on the 9" deep ballast bulb and the antifouled bottom is largely suspended in mid air, out of the mud for about 2-3' fore, aft and sideways.

Sorry, hope you've had your supper !

This was a particularly bad season, obviously pre-power wash; the central brown bit does show around the ballast bulb...

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