Bottom painting a 21'

Rich M · Mar 28, 2015

Based on the information you provided if it were my boat I'd sand the bottom with a medium grit paper to ensure adhesion, paint it, put it in the water and ENJOY the sailing season.

Chuckdenik · Mar 28, 2015

If you only have minor flaking of the old bottom paint and the fiberglass underneath is solid you probably don't need a barrier coat. Just scuff up the bare spots, wipe with solvent, and put your bottom paint on. Only need barrier coat if bad blisters and/or large scuffs in the gel coat. If you have to do barrier coat, it's a lot of work sanding off all the old bottom paint and fairing them bottom, then at least 4 coats of 2 part epoxy, but not a horrible task.

Joe · Mar 29, 2015

You're worrying way too much. Follow the instructions on the can of bottom paint you own.... do it yourself.... and save 400 bucks... you'll spend some money on supplies and jacking your boat up... but that's it.

At the end of the season, you can inspect the bottom when you haul it out and see if any thing has happened.. which it probably won't.

Just a heads up, even with anti fouling paint... you will get some growth.. mostly algae.. so it's not a bad idea every month or so to grab a piece of old carpet, pull the boat into shallow water, or don the mask and snorkel, and wipe it off... If it's wet it comes off easily... if you wait till you haul out the boat and it gets dry... it's way more difficult to remove.

BobM · Mar 29, 2015

Be prepared to get your hands dirty or sell the boat. Marinas will just do a lousy job and take your money. Ablative is very forgiving. Keep in mind that the paint flakes are toxic so use a dust mask, drop clothes and perhaps a shop vac if it is really flaking badly.

Crazy Dave Condon · Mar 29, 2015

slogfish;

are you in north Carolina..

CloudDiver · Mar 30, 2015

I just completed a full bottom job/blister repair on a 22 ft boat, and yes, it is a horrible job. If your gelcoat is present and not damaged you should be just fine. Most people will probably argue that gelcoat itself is NOT a barrier coat because polyester resin based gelcoat is not really waterproof... Technical arguments aside, it takes years of being in the water for water molecules to permeate through gelcoat and become trapped between the fiberglass and gelcoat or deeper in the glass to cause blisters. Since your boat was probably trailered most of its life it has always had plenty of time to dry out between water time.
So I echo the suggestions above, wear a mask and eye protection, scrape away loose flakes and then sand with medium grit paper... apply your new bottom paint and go enjoy the season. Your boat won't be sitting in the water long enough to absorb water through the gelcoat before you pull it back out.

Ken Cross · Mar 30, 2015

I connect my orbital sander to a shop vac. I just remove the dust bag and duct tape a vac hose to it. Very little dust escapes.

Also cleaning the boat in the water is illegal in many areas (like where I live.) You may want to know before you expose yourself to legal problems.
Ken

fstbttms · Mar 31, 2015

Ken Cross said:
Also cleaning the boat in the water is illegal in many areas (like where I live.)

Umm... Not really.

In Washington, cleaning of ablative paints is forbidden. Otherwise, anything goes. No other state has restrictions on in-water hull cleaning. The Port of San Diego has implemented an edict that professional hull cleaners cannot create a "plume" of color while cleaning. Which in essence means they cannot clean ablatives. Boat owners doing their own cleaning are not restricted however. They can do whatever they like in this regard.

There are no other government restrictions anywhere else in the country, at this time. Individual marinas may have policies concerning in-water hull cleaning, but these do not involve any legal issues.

Crazy Dave Condon · Mar 31, 2015

Slogfish;

Are you working on your boat across the river from Newbern in the do it yourself yard where the old men sit and drink coffee in the office? My email address is davecondon@mindspring.com and I know the area of Newbern and Oriental all too well. They know me as Crazy Dave

Sunbird22358 · Mar 31, 2015

The only problem that I can see is what kind of paint is on the boat now? Some paints are not compatable with old finishes and may cause the old coating to flake off, leaving bare patches on the boat. This is mostly a problem only when applying a "vinyl-based" paint over a non-vinyl-based paint, but check the info on your new paint for any compatibility issues. The other potential issue would be if the old paint were one of the Teflon-based paints sometimes used in freshwater, but it doesn't sound like that is what the old paint was. Most recomend removing the old paint if it is flaking or of unknown type. In general though, a good thorough washing of the old paint surface to remove any dirt or scum/algea then thoroughly sanding with 80 grit paper and thoroughly wiping off the surface after, will be prep enough. I sand the bottom (after scraping any loose areas) of my boat (17' O'DAY) each year with a wallboard screen sanding pad, wipe it down with a rag, then apply the new paint (lately either Petit UnEpoxy or Interlux FG Bottomkote) with a small roller. Despite carefull scraping of loose areas (and checking for such areas over the whole bottom) I still get chips that flake off while I'm applying hte new coat of paint. One of these years I'll sand/scrape/remove all the old paint (last scraped bare in 1997) but I don't look forward to the mess!
Don't forget to paint as much of the retractable keel as you can get to, and under the trailer rollers/bunks. On our old CAL 21 we were not on a trailer, the boatyard had us on an A-frame roll-around cradle, so we could lower the keel enough to paint most of it and up into the keel trunk as well. On my DS II I am able to move the boat half-way off the trailer by supporting hte stern on a saw horse, so I can lower the CB about 2/3 and paint it and the trunk, as well as the areas normally blocked by the trailer bunks and rollers.

Also, check your boatyard, do they have any restrictions on sanding? Some places require that you use a sander hooked up to a "hepa" vacuum to collect the dust. Others may have special areas reserved for sanding, check before starting.

Crazy Dave Condon · Apr 1, 2015

Just make sure you are careful with blocking that boat up by yourself Slogfish. Feel free anytime to contact me as I was a dealer in that area for a long time and know about the smaller boats.

Kermit · Apr 1, 2015

Crazy Dave Condon said:
They know me as Crazy Dave

Wow... Who woulda thunk it?

Chuckdenik · Apr 1, 2015

One other thing to consider - if the boat was always trailer launched your keel probably doesn't have a zinc. If it's made from steel (unless totally enclosed in fiberglass) and you plan to keep it in all season it would be a good idea to add one to prevent corrosion. A "disk" zinc should work well. It's work to drill a hole through the keel board to mount it the first time, but not too bad.

fstbttms · Apr 1, 2015

A zinc anode will do nothing to stop rust. In fact, on a pice of iron that big, most common anodes will be insufficient to protect against electrolytic or galvanic corrosion as well.