Wet sand bottom - What grit?

Overdraft

New Member
I was going to wet sand my hull as it has some oxidiation... Do you guys recommend this and if so, 400? 600? 1200? and then should I wax afterwards? Thanks for the input!
 
You start with a lower number and then move up (1200 would be high enough). Depending on how bad your hull is i'd start with 400 or 600, and move up from there. There are some good articles on drlaser.org about this.
 
Wet sand to start but finish with a buffing comound. Marine buffing compound for Gel coats. NOT Automotive compound. Around a 2000 compound. Lots of Water and a variable speed polisher. Great finish. Like out of the factory. I do not beleive in wax. Some do. To each his own.

Steve.
 
IMHO, 1200 is the coarsest acceptable to finish finish. If you have time, follow the 1200 with a finer paper or with toothpaste.

If you have to start with 400 or coarser, keep in mind that the hull can take only three or four sandings in its lifetime before the glass will start showing through the thinning gelcoat. That gelcoat is a limited resouce!

Over the years, I have preferred using a "fiberglass color restorer" compound (rather than wetsanding) for improving the cosmetic appearence of the hull, reserving the wet-sanding option only to those cases where I had to remove scratches from the hull (such as prior to major championships, or before selling the hull).

Also, if sailing in polluted waters or muddy rivers and lakes, applying a Teflon marine polish (NOT wax) as a finishing coat does wonders for keeping that hull clean all season long. Wax, causing separation of the "boundary layer" of water from the hull, is no good for the performance of racing hulls.

Shevy Gunter

Determined Not to Waste My Fellow Sailors' Time by Forcing Them to Check My Profile to Figure Out Who The Hell This Author Is
 
Determined Not to Waste My Fellow Sailors' Time by Forcing Them to Check My Profile to Figure Out Who The Hell This Author Is
This is annoying, I have updated the template to display the Full Name and Sail Number with the post. I would also encourage you to upload an avatar/picture to go with it. Also, please check your profiles and make sure all the information is correct.
 
"1200 is the coarsest acceptable to finish finish. If you have time, follow the 1200 with a finer paper or with toothpaste."

If you use toothpaste, what should you apply it with, I've never heard of using toothpaste. It probably leaves your boat smelling fresh too.
 
A 1200 or 1500 grit is adaquate and gives a similar finish to rubbing compound. A rubber sanding block seems to work better than a buffing wheel, as a buffer is designed to 'melt' paint. A 600 grit can be used to knock-off bad scratches.

The secret is to use plenty of water (or other fluid). A sanding block in one hand and a 12-oz brew in the other works well. Share some of the beverage with the boat and the job passes quickly...rinse well afterwards.
 
> If you use toothpaste, what should you apply it with, I've never
> heard of using toothpaste.

Actually, toothpaste (not the "gel" kind) is quite commonly used to finish any gecoat repairs.

Just apply with a piece of clean, soft, wet cotton cloth. Light, circular motions are sufficient. No need to use a rubber or foam sanding block to rub the toothpaste: toothpaste is so fine that circular rubbing motions will not distort the surface.

To justify the time and effort required, you can just select a one square foot area and apply the toothpaste only inside the selected area. Then, just compare the reflections of some complex background object (e.g., leaves of a plant) inside and outsite of the perimeter of the finished area. You'll be able to see the difference.

I get bored and apply the toothpaste only to the forward 1/3 and aft 1/3 of the hull, and only under the waterline.

I you are THIS picky about your hull finish, then also note that what's an order of magnitude more important is the smoothness of the surface of your auto-bailer!

SG
 

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