Bottom paint strip and re-do

[Seaway85]

The bottom paint on the 2000 2300 DVCC I bought last year is in rough shape in some spots. There are entire sections flaking off down to what I'm assuming is the barrier coat, and there are some scuff marks closer to the stern that look like the gelcoat is showing through. I've decided to strip everything and start fresh, and I wanted to check my process with the experienced minds of CP before I get going:

1. Strip the hard bottom paint. I have several gallons of Dumond Smart Strip, scrapers, a powerwasher, and my hopefully-prepared willpower and muscles. I did a quick test on the transom last weekend: in cool weather (under 50deg) with 2-3hrs of incubation I was able to scrape off at least 1/2 of the paint's thickness. I'm hoping that with 60-70deg whether and 6hrs incubation I can get most of the paint off in the first coat, but let me know if I'm being overly optimistic and what else I can do to make this easier!
2. Strip and/or sand off the barrier coat. Here's one part I'm unsure about. Will the Smart Strip take off the barrier coat? Dumond's other products claim they won't harm the barrier coat, but I can't find any similar claim for Smart Strip, which is good because I want to remove the barrier coat and start fresh. If Smart Strip won't do the job, is there something else I can use besides sanding? Or am I misguided to want to take off all of the barrier coat and start fresh?
3. Deal with problem areas/repairs. There are at least 2 spots where, even if I don't take all of the barrier coat off the boat, I'd like to do so at these spots: holes in the transom left from an old transducer, and the area around the seacock strainer/pickup. I've picked up a lot of good advice on CP for over-drilling screw holes, wetting them with unthickened epoxy, filling with colloidal sillica-thickened epoxy, fairing/sanding, and re-drilling. I've read lots of helpful info on CP for replacing the seacock as well. There are also a few spots with scuffs/scratches where I'll use epoxy to seal up the scuffs to avoid water-intrusion. I don't see any signs of blistering now, but if I find any after removing paint then I'll grind down the area a bit before wetting/filling/fairing with epoxy.
4. Prep the whole boat for paint. I'm assuming that to finish removing all of the barrier coat I'll need to sand the whole hull, but even if not then it's best to prep the gelcoat with some 80-grit and a good cleaning before painting. Any epoxy from repairs would be cleaned to remove blushing and sanded to prep for paint as well.
5. Barrier coat. Paint the hull with 2 coats of something like Interprotect. Is 2 coats enough? Should I bond the new seacock strainer over the barrier coat, or should I bond to the bare gelcoat?
6. Bottom paint. I'll be going with a multi-season ablative. Something like Pettit Odyssey HD (especially because it's on sale right now), but I'm open to suggestions for ablative paints for Massachusetts waters. The plan is to start with a signal coat of blue and then 2 coats of black, with maybe a 3rd at the waterline. A few questions: should I "hot-coat" between the last barrier coat and the first ablative coat? If I don't, does the barrier coat need to be sanded? Is 3 coats of ablative overkill or just right for a ~2-season job?

I know from previous posts here and elsewhere that this is a ton of work and having a yard do it would be more efficient, but with my wedding in the fall that's just not in the cards. PLUS, I'll feel damn-good (if not totally drained and defeated) after it's done. I'll be taking the boat off the trailer tomorrow, and I'm hoping to have some good weather next weekend to get the stripping started.

If at this point you're still reading and ready to answer questions or tell me I've got everything wrong then THANK YOU! I've been reading and thinking about this process for way too long now and I'm excited to get to work.

 

[shawnee83]

It sounds like a good plan. I respect your ambition on this project. Now that I’m closer to 60 than 50 I’ve learned to let go of certain things. Sometimes it’s best to pay the pro’s (if they are truly pro’s?) rather than do it yourself. I’ve just dropped mine off to be stripped, barrier coated and bottom painted. I’m expecting a big bill for the job but it will be done in a few days and I just don’t have the time. I’ll share the financial beating with you and you can compare if your savings was worth it. Looking forward to seeing the finished project. Good luck.

 

[Andy]

It sounds like a good plan. I respect your ambition on this project. Now that I’m closer to 60 than 50 I’ve learned to let go of certain things. Sometimes it’s best to pay the pro’s (if they are truly pro’s?) rather than do it yourself. I’ve just dropped mine off to be stripped, barrier coated and bottom painted. I’m expecting a big bill for the job but it will be done in a few days and I just don’t have the time. I’ll share the financial beating with you and you can compare if your savings was worth it. Looking forward to seeing the finished project. Good luck.

It took me a long time to learn to let the pros do some of the work on our boats;
(so you're close to 60!?!... it's nice to hear some of you youngsters are faster-learners than I am! ☺)

 

[Seaway85]

It sounds like a good plan. I respect your ambition on this project. Now that I’m closer to 60 than 50 I’ve learned to let go of certain things. Sometimes it’s best to pay the pro’s (if they are truly pro’s?) rather than do it yourself. I’ve just dropped mine off to be stripped, barrier coated and bottom painted. I’m expecting a big bill for the job but it will be done in a few days and I just don’t have the time. I’ll share the financial beating with you and you can compare if your savings was worth it. Looking forward to seeing the finished project. Good luck.

I'm definitely curious to hear what the bill is. Part of me is still on the fence about having a mobile sandblasting service come and take the paint off, but I haven't hit 30 yet so I feel like it's something I can tackle...
I'll definitely post some pictures during the process!

 

[tomc585]

I priced out soda blasting 2 years ago on my old welcraft 180. He wanted $800. I just couldnt justify that for a $2500 boat.

 

[camron]

I paid around 1200 to have my 2120 done.

I also had to use the dummond stripper on the sides of the hull as the previous owned had just been covering up the scum line with more paint... that product works good, a little bit of soft scrub and a stiff bristle brush will remove a lot of additional paint once the chemical softens it up.

 

[Seaway85]

I paid around 1200 to have my 2120 done.

I also had to use the dummond stripper on the sides of the hull as the previous owned had just been covering up the scum line with more paint... that product works good, a little bit of soft scrub and a stiff bristle brush will remove a lot of additional paint once the chemical softens it up.

I'm glad the Dumond stripper worked for you. Did you use the peel away sheets they sell too?

 

[camron]

Yes the rolls work well. Just make sure it stays moist. I had a spray bottle and just gave it a mist when needed

 

[got_em_on]

We did this in 2013 and had a company do it for us-soda blast, barrier coat, Interlux Micron Extra indicator coat of black and 2 more of blue. We just hit the bottom with a scotch bright pad and a little on/off when we haul out in december-no more power washing to go easy on the paint. Then just touch up in the spring. We literally used only 1 gallon of bottom paint for touch ups from 2014 to 2020. At $270 gallon for paint the bottom strip paid for itself.

Your taking on a big job-I would price out your material list, factor in time lost from family/friends, missed fishing trips and other projects you could have been doing on the boat/house etc. and then get a quote on getting it done by a boat yard. This is not something you are going to do ever year so you will only cry once writing out the check!

 

[Key Largo]

The bottom paint on the 2000 2300 DVCC I bought last year is in rough shape in some spots. There are entire sections flaking off down to what I'm assuming is the barrier coat, and there are some scuff marks closer to the stern that look like the gelcoat is showing through. I've decided to strip everything and start fresh, and I wanted to check my process with the experienced minds of CP before I get going:

1. Strip the hard bottom paint. I have several gallons of Dumond Smart Strip, scrapers, a powerwasher, and my hopefully-prepared willpower and muscles. I did a quick test on the transom last weekend: in cool weather (under 50deg) with 2-3hrs of incubation I was able to scrape off at least 1/2 of the paint's thickness. I'm hoping that with 60-70deg whether and 6hrs incubation I can get most of the paint off in the first coat, but let me know if I'm being overly optimistic and what else I can do to make this easier!
2. Strip and/or sand off the barrier coat. Here's one part I'm unsure about. Will the Smart Strip take off the barrier coat? Dumond's other products claim they won't harm the barrier coat, but I can't find any similar claim for Smart Strip, which is good because I want to remove the barrier coat and start fresh. If Smart Strip won't do the job, is there something else I can use besides sanding? Or am I misguided to want to take off all of the barrier coat and start fresh?
3. Deal with problem areas/repairs. There are at least 2 spots where, even if I don't take all of the barrier coat off the boat, I'd like to do so at these spots: holes in the transom left from an old transducer, and the area around the seacock strainer/pickup. I've picked up a lot of good advice on CP for over-drilling screw holes, wetting them with unthickened epoxy, filling with colloidal sillica-thickened epoxy, fairing/sanding, and re-drilling. I've read lots of helpful info on CP for replacing the seacock as well. There are also a few spots with scuffs/scratches where I'll use epoxy to seal up the scuffs to avoid water-intrusion. I don't see any signs of blistering now, but if I find any after removing paint then I'll grind down the area a bit before wetting/filling/fairing with epoxy.
4. Prep the whole boat for paint. I'm assuming that to finish removing all of the barrier coat I'll need to sand the whole hull, but even if not then it's best to prep the gelcoat with some 80-grit and a good cleaning before painting. Any epoxy from repairs would be cleaned to remove blushing and sanded to prep for paint as well.
5. Barrier coat. Paint the hull with 2 coats of something like Interprotect. Is 2 coats enough? Should I bond the new seacock strainer over the barrier coat, or should I bond to the bare gelcoat?
6. Bottom paint. I'll be going with a multi-season ablative. Something like Pettit Odyssey HD (especially because it's on sale right now), but I'm open to suggestions for ablative paints for Massachusetts waters. The plan is to start with a signal coat of blue and then 2 coats of black, with maybe a 3rd at the waterline. A few questions: should I "hot-coat" between the last barrier coat and the first ablative coat? If I don't, does the barrier coat need to be sanded? Is 3 coats of ablative overkill or just right for a ~2-season job?

I know from previous posts here and elsewhere that this is a ton of work and having a yard do it would be more efficient, but with my wedding in the fall that's just not in the cards. PLUS, I'll feel damn-good (if not totally drained and defeated) after it's done. I'll be taking the boat off the trailer tomorrow, and I'm hoping to have some good weather next weekend to get the stripping started.

If at this point you're still reading and ready to answer questions or tell me I've got everything wrong then THANK YOU! I've been reading and thinking about this process for way too long now and I'm excited to get to work.

My 23DVCC 2001 recieved it's first bottom coat in 2015 after being stored on a rack prior. I had a large marina in Key Largo, pressure wash and lightly sand where necessary the hull which was already in good shape, apply a primer coat then 2 coats of West Marine PCA, 3 coats in the stern and along the chines. In Key Largo kept in the ocean on a mooring for 10 months of the year in 2 to 5 feet of water swinging free from the bow ring which helps somewhat to reduce growth compared to stationary at a dock, I get about 7 months, before I pressure wash at the First sign of any barnacles by laying the boat on the shore with the tide receding pressure wash 1 side per day. The water temperature ranges from 77 to 87 degrees. I have painted it my self since then every September/October on the trailer when I perform the annual Yamaha 100 hour service.
,

 

[shawnee83]

We did this in 2013 and had a company do it for us-soda blast, barrier coat, Interlux Micron Extra indicator coat of black and 2 more of blue. We just hit the bottom with a scotch bright pad and a little on/off when we haul out in december-no more power washing to go easy on the paint. Then just touch up in the spring. We literally used only 1 gallon of bottom paint for touch ups from 2014 to 2020. At $270 gallon for paint the bottom strip paid for itself.

Your taking on a big job-I would price out your material list, factor in time lost from family/friends, missed fishing trips and other projects you could have been doing on the boat/house etc. and then get a quote on getting it done by a boat yard. This is not something you are going to do ever year so you will only cry once writing out the check!

My hope and plan is to handle the touch ups myself the same way. Hopefully for the next many springs. Letting the yard guys do the heavy lifting (sanding, raising the water line, barrier coat etc..) this year to get everything right.

 

[Seaway85]

Your taking on a big job-I would price out your material list, factor in time lost from family/friends, missed fishing trips and other projects you could have been doing on the boat/house etc. and then get a quote on getting it done by a boat yard. This is not something you are going to do ever year so you will only cry once writing out the check!

Well, got_em_on was right...

I attempted to start the job this past weekend and I called it quits 8 hours into it. Friday night I spent ~4hrs applying the Dumond paint stripper to the entire hull and papering over it to keep it moist overnight. Saturday afternoon I started power-washing and scraping away and had barely gotten anywhere after 4 hours. Here are some pictures just for fun (and in case anyone else is curious about how this stuff works):

#1 is a picture to get an idea of the condition of the bottom paint on the boat
#2 is the hull all Dumond stipper-coated and papered-up
#3 shows the extent to which I was able to get paint off with the power washer. Some spots came off more completely, but most of the paint was still pretty solid after 12+hours of sitting with the stripper.
#4 hurts a little. I'm guessing this spot was already in bad condition underneath the paint, but also I was probably a little too overzealous with the pressure washer.

Using the paint scraper was physically demanding as expected, and it worked a little too well and was very difficult to use delicately and not take off a layer of gelcoat underneath the paint. The whole thing was pretty defeating, and I had to keep reminding myself (and still do) that I never would have made the decision to pay someone to do it without first trying myself.

I found a guy on the south shore who runs a $90/ft deal. Bring the boat to his yard, he'll sandblast, prep the bottom, 2 coats of barrier, and then 2 coats of Cukote with a 2yr warrantee. Gelcoat repairs are extra, obviously, but his reviews claim that he's very reasonable. It felt so good hanging up from that call after confirming a spot on his work list. FYI every mobile sandblasting service in the Greater Boston area that I called quoted me $50/ft.

The question is... he can't get to my boat until around Memorial Day. I REALLY want to use the boat before then, but now have even more bare spots on the bottom than before. Can I get away with patching over the spots with paint and having the boat in the water for a couple of days? It seems risky, especially because now the paint is even more compromised due to the stripper, but the fish are calling...

I'll update here with my thoughts and final cost once the job's done. In the meantime, I'm moving on to projects elsewhere on the boat. Stay tuned!

 

[pelagic2530]

The only thing the bottom paint does for you is prevent fouling of the hull due to marine growth on the hull. The worst thing you're going to have happen with partially scraped-off paint is you'll probably get some scum forming on the hull in pretty short order. No big deal, as you're going to have the boat hauled, pressure washed, and blasted soon anyway; a month's worth of scum buildup isn't going to hurt you. Personally, I wouldn't even bother with touch up paint; seems like a waste.

If you've got spots where the fiberglass mat is exposed, I might slap a quick coat of epoxy over them to prevent water intrusion.

The caveat being that you're already scheduled to get the boat blasted, painted, and have the glass repair work done in a month or so. If you were going longer than that, I'd suggest a more permanent repair.

Get the boat in the water and go fishing!

 

[Seaway85]

The only thing the bottom paint does for you is prevent fouling of the hull due to marine growth on the hull. The worst thing you're going to have happen with partially scraped-off paint is you'll probably get some scum forming on the hull in pretty short order. No big deal, as you're going to have the boat hauled, pressure washed, and blasted soon anyway; a month's worth of scum buildup isn't going to hurt you. Personally, I wouldn't even bother with touch up paint; seems like a waste.

If you've got spots where the fiberglass mat is exposed, I might slap a quick coat of epoxy over them to prevent water intrusion.

The caveat being that you're already scheduled to get the boat blasted, painted, and have the glass repair work done in a month or so. If you were going longer than that, I'd suggest a more permanent repair.

Get the boat in the water and go fishing!

Good point with the epoxy instead of paint. I just want to prevent water intrusion so I’ll patch it up and get it in the water as soon as the new thru-hull’s in place.

 

[BenTerrible]

I am curious the outcome, did you wind up having this done by the mentioned boat yard, or did you finish the job yourself?

I came here to search for others who have taken on this job, as I am/was considering it for my 2520. The bottom paint is literally coming off the boat in chunks. In a perfect world, I would love to go back to the gel coat finish on the bottom of the boat, as I store it indoors, out of the water.

I am being quoted north of $3K to completely remove the bottom paint and apply new bottom paint. I would rather send that money into my new electronics fund for the boat!

Don't mean to hi-jack the OP's thread, but here is what I am dealing with. It looks very similar to the OP's bottom paint. Is this ablative or hard epoxy bottom paint?

 

[baker]

I am curious the outcome, did you wind up having this done by the mentioned boat yard, or did you finish the job yourself?

I came here to search for others who have taken on this job, as I am/was considering it for my 2520. The bottom paint is literally coming off the boat in chunks. In a perfect world, I would love to go back to the gel coat finish on the bottom of the boat, as I store it indoors, out of the water.

I am being quoted north of $3K to completely remove the bottom paint and apply new bottom paint. I would rather send that money into my new electronics fund for the boat!

Don't mean to hi-jack the OP's thread, but here is what I am dealing with. It looks very similar to the OP's bottom paint. Is this ablative or hard epoxy bottom paint?

It looks like ablative. Is there a primer coat, pictures are a little blurry?
I have been told that ablative anti-fouling bottom paint doesn't like to be out of the water.
There are others on here that have tackled the bottom paint stripping task, do a search.
I would try stripping myself if time wasn't a factor and money was tight, but do a small test area first and see how it goes.

 

[BenTerrible]

Unsure of a primer coat, my guess is yes. I do see some kind of green paint/undercoat in some spots where the bottom paint has flaked off.

 

[gregd123]

I looked into removing bottom paint earlier. I haven't tackled this yet but it is on the to do list.

Here is an excerpt of the exchange I had with GoodChance:

GoodChance:
Ohhhh ..... well that's a little more involved.

The easy way is to hire someone with a soda blaster but you'll risk ending up with a bottom that must be re-painted because it will be so rough.

Mine? On several boats I started with 120 grit on an 8" Dewalt orbital sander/polisher. Remove the paint with 120 just until you start to see the underlying gelcoat and no further. Then move to 220 remove the remaining bottom paint and go until you see full gelcoat. Then use a pencil or dye marker across the entire bottom (as a guide coat) and again go across the entire bottom with 320. More pencil. Then 600. More pencil. Then 800. Then use a polishing compound on a wool pad and a Dewalt 8" sander/polishing machine. You can go 1 additional step and add polish after compound but I didn't.

Me:
Everything makes sense except maybe the "penciling". Are you saying scribble all over the bottom with something like a carpenter's pencil? Do you just put a bunch of x's or the like or should the penciling create more of a dense pattern?

GoodChance:
The "pencil" is your guide.

After sanding the bottom with say 220 grit, you'll scribble like a 3 year-old girl (or boy) across the entire bottom of the boat. Everything. Then when you sand with 320 grit, you'll be able to see where you have sanded and where you haven't.

It is an involved, tedious process. It's not easy. But the results are worth it if you have bottom paint and now keep the boat on a trailer or lift. The initial sanding with 120 grit takes the most time and is the most labor intensive. Subsequent sanding with finer grit goes much faster. As a point of reference, on my 26ft boat with 2 layers of bottom paint, it took about 30 hours of sanding to remove all the paint, compound and polish.

I picked-up 2 - 2.5mph at all rpm and a slight increase in fuel economy by removing the bottom paint. Plus, the boat looks tremendously better.

 

[Seaway85]

I looked into removing bottom paint earlier. I haven't tackled this yet but it is on the to do list.

Here is an excerpt of the exchange I had with GoodChance:

GoodChance:
Ohhhh ..... well that's a little more involved.

The easy way is to hire someone with a soda blaster but you'll risk ending up with a bottom that must be re-painted because it will be so rough.

Mine? On several boats I started with 120 grit on an 8" Dewalt orbital sander/polisher. Remove the paint with 120 just until you start to see the underlying gelcoat and no further. Then move to 220 remove the remaining bottom paint and go until you see full gelcoat. Then use a pencil or dye marker across the entire bottom (as a guide coat) and again go across the entire bottom with 320. More pencil. Then 600. More pencil. Then 800. Then use a polishing compound on a wool pad and a Dewalt 8" sander/polishing machine. You can go 1 additional step and add polish after compound but I didn't.

Me:
Everything makes sense except maybe the "penciling". Are you saying scribble all over the bottom with something like a carpenter's pencil? Do you just put a bunch of x's or the like or should the penciling create more of a dense pattern?

GoodChance:
The "pencil" is your guide.

After sanding the bottom with say 220 grit, you'll scribble like a 3 year-old girl (or boy) across the entire bottom of the boat. Everything. Then when you sand with 320 grit, you'll be able to see where you have sanded and where you haven't.

It is an involved, tedious process. It's not easy. But the results are worth it if you have bottom paint and now keep the boat on a trailer or lift. The initial sanding with 120 grit takes the most time and is the most labor intensive. Subsequent sanding with finer grit goes much faster. As a point of reference, on my 26ft boat with 2 layers of bottom paint, it took about 30 hours of sanding to remove all the paint, compound and polish.

I picked-up 2 - 2.5mph at all rpm and a slight increase in fuel economy by removing the bottom paint. Plus, the boat looks tremendously better.

I can't speak to the process of removing bottom paint to leave the gelcoat bare for rack or trailer storage, but I do know that even with coarser grit, sanding all of the bottom paint off a 20+ft boat will be an arduous task. It took my dad and I almost an entire day on my last boat (17' Seaway), and we didn't even bring it down to the gelcoat.

BenTerrible, I've read that soda blasting can leave a sort of dimpled surface after the process, which isn't conducive to a smooth, bare, gelcoat bottom. I've also heard that different media in the soda blasting process can do a better job than others, so it might be worth talking about that to the blasting people to see if they're up for the task. $3k is definitely more expensive than what I was quoted for, but comparing San Diego to Boston might be like apples to oranges...

FYI, the job hasn't been done yet, but the guy who's doing the job called me yesterday to say he's ready for the boat. Crossing my fingers I can get it in before Memorial Day and will keep you guys posted on how it comes out.

 

[shawnee83]

I told you I would share the final outcome. $1,500 and done. Sanded, raised water line, barrier coat and bottom paint. It just depends where you are and who you use....and some good luck with the last part. I’ll do the touch up coats goin forward.