Bottom paint

[Maverick1958]

I have a 22 foot trailerable boat in need of a new bottom job.
1. What is the best way to remove the old bottom paint or should I just sand it and paint over it.
2. How do I paint the places I can not get to because of the supports?
3. How do I raise the boat to drop the keel for paint without a crane?
4. Is bottom paint a plus or minus for a trailerable boat?
5. I want to do this myself.

[NICHOLSON58]

If you trailer it out as the regular mode of storage, meaning you "dry-sail" then you don't need antifouling or sealers. Just clean & wax it. If the bottom is a wreck and you want to make it look great then use good under water suitable epoxy & fillers such as MAS or West System or any of the other high end marine materials. Ordinary stuff sold in hardware stores and Home Depot will not hold up to immersion.

If you are not using a yard you may want to make or rent a rig to help you lift and chock the boat in some convenient orientation. If you research this a bit you will find this is ground many have plowed before you. I have seen a number of boats on this site and in some of the sail publications showing how others have made boat lifts. Consider one side at a time. You could place it on timbers and let it tilt on its side. I have seen even very large boats (44 ft) flipped over completely.

After all repairs and fillers are applied, sand it fair finishing with about an 80 to 120 grit (read the paint recommendations on this). Probably the best paint you can apply is AWL GRIP. It is a bit touchy but can give you a like-new finish that will last many years. I never change the color from the original gel coat so that minor scratches are not so obvious.

If you are removing old antifouling paint the removal process may be effected by the old paint. Some paints are very friable and sand or scrape off easily. Some are tar-like and fill a sander in an instant. For these I use a 4-ft. floor scraper and keep the blade like a razor. You can also consider using some of the chemical strippers. Use only chemicals compatable with fiberglass. Search on line for aircraft stripper or go to a car supply store and buy stripper for a corvette. NOTE that botom paint is toxic. Get a good respirator with a full nose and mouth rubber mask and cannisters. The disposable paper things are worthless. Be aware of where your dust and chemicals are going especially if others are around.

I found that for large sanding jobs a 9-inch rotary variable speed buffer outfitted with a semi-ridgid flat disk and 40 or 60 grit (Home Depot) is very fast. I faired the entire bottom of our 58 footer in 3 days with one. The other really useful tool as yo get closer to final prep is a dual action orbital sander. I prefer the hook and loop face (Velcro) for attaching the paper. The blue 60 through 120 grits from Home Depot hold up well for this.

Do you really need to paint the keel - or is it a swing centerboard?

If you intend to leave it in the water for long periods then finish using a good bottom sealer such as Interprotect 2000E and then apply antifouling. Trailering is much easier.

West Marine West System has a nice video on bottom repair, blisters, painting.