Sanding, stripping hull to gelcoat - cost/time?

[TheThunderbird]

OMG.. it is my turn now, to get it done.

Health hazard is more painful than any 000s$

Fairing, we can do it together with a pro.

[laika]

I had my boat peeled down to bare fiberglass a few years back. I'm sure someone in Deltaville has a peeler. Similar in cost to blasting. Basically, they set the appropriate depth on the tool and it shaves off paint/gelcoat in strips, exactly how much you want and in a uniform way. It took the guy about 6 hours to do my 27'.

[Suijin]

Originally Posted by hsi88

Thank you for your replies. You answered all my questions. I just turned 61 about a week ago. 50+ hours of scraping or sanding seems pretty grueling. In practice, I never plan for more than 4-6 hours of actual labor in a day when I work on any project. And often, it becomes 2-4 hours as I tend to stop to mess around with tools or "scope things out".

No matter what I choose to strip the hull, finish sanding and fairing will probably take at least a couple additional weekends. I would love to save the $1500, but if I subtract the price of sanding disks and other supplies, driving 8 hours round trip and paying for at least one night in a local motel (boat is not set up for overnights), that $1500 is starting to sound pretty good.

Whatever method you chose to do it yourself, it would be more than one night in the motel, that's for sure.

As for blasting it yourself, even if your little blaster would work there are environmental requirements. At most yards the boat needs to be tented to capture all the material, and most techs are set up with breathing air from the outside. It's not as simple as loading media and letting her rip. All the yards in Deltaville do decent work at a fair price. You'll be happy with the result. The sanding after blasting is not a huge job and goes pretty quickly, and the fairing of course is dependent on what gets revealed.

I'm a big believer in lots of barrier coat...at least for and upwards of six to eight coats, depending on the viscosity of the product you choose. After the initial fairing of obvious flaws, after the blasting and sanding, put a couple of coats of barrier on, let it kick fully, and all the imperfections you missed will then be obvious. Fill and fair again as required, sand the whole thing for tooth, and apply the remaining coats.

[Suijin]

Originally Posted by lancelot9898

Have you asked the yard the price to peel the paint off? I had a peel job done about 5 years ago and it was a double peel into the gell and the chopped strand mat and was not much more than 2K there in Deltaville. Just removing bottom paint on a smaller boat should not be that much and there are some advantages to the peel vs blasting. FWIW

Why would you peel a boat if there are no obvious issues with the gel and laminate other than old bottom paint? That's sort of like opting for open heart surgery when you feel a bit of heartburn after a bowl of chili.

[a64pilot]

Originally Posted by Suijin

Why would you peel a boat if there are no obvious issues with the gel and laminate other than old bottom paint? That's sort of like opting for open heart surgery when you feel a bit of heartburn after a bowl of chili.

He did mention blister repair and fairing at a later time.
I was under the impression if there were many blisters, that peeling and letting it sit for months to be an acceptable procedure?
Depends on I guess what blisters means

[Tetepare]

I can speak to this, as I did it on my C30. It was, by far, the worst project I have ever tackled.

I used a big belt sander to removed the old skul paint (intent was to de-blister and apply VC17). That took two days with a sander over my head. I was completely covered with paint dust for weeks.

Note that this method you don't get to elect to stop at the gelcoat. So a barrier coat had to be applied. IIRC I used Interlux which has a time period (IIRC 2 hours) between coats. Applying the barrier coat took some 12 hours, including a few breaks.

As I finished my horrifying project, another boat owner stuck chemical stripper strips (kinda like paper or tyvek with chemical on one side) on his underside. I don't know how, but they stuck to the hull. When he removed them the bottom was 95% clear and he still had the gelcoat.

Needless to say, after seeing that I was near suicide.

If I ever have to do it again, I'll start with the chemical stripper strips. I don't care if they work or not, or how much they cost. If they remove 10% of the paint it's worth it.

Now, that said: I just had an experimental paint removal project that had to be done indoors. I tried CitriStrip (non toxic, no fumes) which you can get at Walmart, and it worked great. I mean, shockingly successful. Yes, had to go over some parts a second time. Right now I'm thinking if I had to do my C30 again and the paint stripper strips were prohibitively expensive, I'd find a way to use CitriStrip.

[Lancerbye]

Back in 2009 I decided to do this on a 44 ft. 13 ft. 9in.beam motor sailer. There was 20 plus years of bottom paint and some was coming off in 1/ 2 to 3/4 in. Chunks. I was quoted 9k as the yard could not use sand blasters, it had to be manally removed. Due to environmental concerns the hull was tarped off and 2 young guys got at it with sanders, scrapers and chemicals. The quote included the cost of 5 coats of Interprotect and 4 coats of good quality ablative bottom paint. It took them 3 weeks working Monday to Friday 8 hours a day just to remove the paint down to gel coat. 1 week to reapply the protective coats and the bottom paint. The final bill was over 18k.
Since you may not know all the different types of bottom paints that were previously applied you will find differences in the rate of removal as you cut through the layers. I would take the offer of sand or soda blasting for 1500.

[Squanderbucks]

I'm voting for your accepting the $1500 bid as long as it definitely includes getting all the paint off. The blasted surface will be better for bonding the barrier coat anyway. At least should be more even. An expert with the sanders can get the bottom nice and level but a newbe with 40-60 grit on a sander can make some serious gouges in the bottom - at least very heavy swirls that then lead to having to fair the entire bottom.

Spend your time on the other things that are less body stress like fairing out any blisters and doing the coatings.

I recommend 2-3 coats of something like E2000 then one or two coats of hard non-ablative paint then 2 coats of ablative if that is what you want for a topcoat.

You will have several hundred dollars in sandpaper alone if you get the good kind like 3M or Norton. Cheaper stuff will work but you will spend your time changing out paper more often and use more sheets/Disks.

[hsi88]

I need to run down to the boat here in the next couple of weeks anyway. Have plenty of other things to do, but will also try cleaning some sections using the citrus stripper, scraping and sanding. Will soon find out how bad the job is. At the moment, the $1500 for blasting is sounding really good. It would have to be pretty darned easy for me not to choose that route.

I appreciate all of your input. A little concerning to hear the horror stories although not surprised. Of all the jobs on a boat, preparing for paint, no matter what the technique or procedure has to be the worst of jobs.

Thanks again!!

[Suijin]

Originally Posted by a64pilot

He did mention blister repair and fairing at a later time.
I was under the impression if there were many blisters, that peeling and letting it sit for months to be an acceptable procedure?
Depends on I guess what blisters means

I think what he's saying is that it would be some trip to the boat after his trip to do the stripping.

Peeling is something you do if the blisters everywhere, large, and into the laminate. While I suppose it's possible to set it so that it just takes off the paint layer, it's basically a power planer and it's going to be near impossible to not remove or ruin the gelcoat which is only @ 25 mils thick. It really strikes me as going at this with an elephant gun unless you have hard evidence that it's required. If the hull is wet, then yes, peeling it allows it to dry out. Peeling can leave a fairly smooth surface in the hands of an experienced user. Minaret could comment on whether its really a viable means of just removing bottom paint alone.

After you peel (to and including the gelcoat), and after repairs, you then have to encapsulate the entire bottom. You can skim it with epoxy or put on endless coats of barrier paint. Either way, it's a lot of work, and certainly expensive if you have a yard do it.

[Kudawudashuda]

Originally Posted by CaptsWife

I have to ask, why? Why do you feel the need to do all this work?

Absolutely. All that old antifouling might be the best barrier coat you have. It breaks my heart to see people labouring weekend after weekend stripping off old AF, and for what? When it comes to antifouling I break all the rules: no surface preparation; big hairy roller; buy the cheapest and slap it on thick; and someone always wants to know how it is that I get 6 months longer out of my antifouling than anyone else.

[Suijin]

Originally Posted by hsi88

I appreciate all of your input. A little concerning to hear the horror stories although not surprised. Of all the jobs on a boat, preparing for paint, no matter what the technique or procedure has to be the worst of jobs.

It's one of those things that if done right and done well, and you maintain it properly in future, you'll never have to do it again.

When you put on the bottom paint, you'll want to hot coat it onto the last coat of barrier. This creates a chemical bond and can virtually eliminate the paint flaking and peeling off down the road, provided you don't let it get too thick in subsequent years. A lot of boat owners (or their yards) are guilty of giving the old coat a quick cursory "scuff" and then slapping on new paint, leading to eventual build up and then failure. You really want to take some of the old paint off, keep the bottom smooth, and minimize the build up. That degree of sanding, every time you paint the bottom, is pretty straightforward and not all that back breaking.

Two things to consider; when you paint the bottom again in a few years, paint it a different color than what you paint it this spring. When the old color starts to show through the new paint, you know it's time for a recoat.

Take a look at Pettit Trinidad paint. It's hard paint, not ablative. It is far more ecologically friendly, and more importantly, it works REALLY well in the Chesapeake. If you sail the boat frequently you can go the first season in the water without any cleaning at all. It's THAT good. Yes it's expensive, but if it saves you a couple of dive cleanings it's already paid for itself.

[UNCIVILIZED]

Not to devalue what some others have said, but the tales of how terrible a job it is to grind off antifouling are a bit overblown. Sure, the 1st or 2nd time you do it, it may (or may not) seem like a nightmare. But from the start, you have to expect to be in coveralls the whole time, with gloves, a mask, ear & eye protection in place. Just as you would with any job involving using a grinder or sander for several days. No one said it's easy, but how often is manual labor? And there are plenty of jobs where guys do things like this daily, for years on end.

Certainly if you've got the coin, consider media blasting. But first check into some of the work the blaster's done in the past, so that you better your odds of avoiding nasty cost overruns. Or poorly done jobs which require more $ than the blasting did, to repair them.

[Three Sisters]

Originally Posted by hsi88

I need to run down to the boat here in the next couple of weeks anyway. Have plenty of other things to do, but will also try cleaning some sections using the citrus stripper, scraping and sanding. Will soon find out how bad the job is. At the moment, the $1500 for blasting is sounding really good. It would have to be pretty darned easy for me not to choose that route.

I appreciate all of your input. A little concerning to hear the horror stories although not surprised. Of all the jobs on a boat, preparing for paint, no matter what the technique or procedure has to be the worst of jobs.

Thanks again!!

We stripped it. After buying the small containers of every label sold at the local home center it was the Jasco paint & epoxy remover that worked. Had high hopes for the citrus products. Some brands were no more effective than spraying with a garden hose. I'm guessing that each performs well for the intended finish to be removed. Then the carbon scrapers with spare blades. The resulting eating away of the ground cover called for several layers of the heaviest rolls of plastic. And protection from the chemical splash. The whole deal became very involved.
A friend at the marina had the hull blasted on their boat. Walnut shells were used with the seperate air supply. The results were a very clean hull with zillions of little pot marks.

I don't know what I'll do next time.

[CaptsWife]

Originally Posted by Tetepare

As I finished my horrifying project, another boat owner stuck chemical stripper strips (kinda like paper or tyvek with chemical on one side) on his underside. I don't know how, but they stuck to the hull. When he removed them the bottom was 95% clear and he still had the gelcoat.

Needless to say, after seeing that I was near suicide.

If I ever have to do it again, I'll start with the chemical stripper strips. I don't care if they work or not, or how much they cost. If they remove 10% of the paint it's worth it.

This? https://www.dumondchemicals.com/pro-...-removers.html

We used a similar product when we were rehabbing a 150 year old house. MUCH easier and safer, both for me AND the environment.