Stripping and repainting 36' Hatt bottom

[ADaily3224]

At the end of the season last year when my boat was pulled for the winter an over zealous yard employee blasted my bottom with a 4,000 PSI pressure washer. There are way too many coats of paint on the bottom, it's very common up north here as the soft ablative pains never wear completely off after only 4 months in the fresh water. The bottom is a mess, layers of paint missing here and there right to the gel coat.
Trying to use a DA sander to fair things out would take half the season. A grinder is way too aggressive so I decided to give the Soy Stripper selling for over $100 a gallon a try. Now I have an even bigger mess, the air temperature was too cool for the sticky stripper to work properly. After scraping and reapplying I finally decided to try the plastic food wrap process. I rolled a generous amount of the stripper onto the hull and covered it with saran wrap. I decided to let it sit all night. I got up early the next morning, headed down to the building where my boat is stored and pulled the wrap off. Everything was pretty soft. I used a 2.5 inch scraper to remove the old paint, it was the consistency of sticky putty, and I didn't get anywhere near all the paint off. This job was turning into a monster. One of my buddies said, "you better call the soda blaster guy". Fine, the guy came down, took a look and some measurements and quoted me $1,200 to $1,400, seems fair to me? But what do I know. I figured I could spend 40 hours with the stripper and putty knife trying to complete the job, and I would never be able to get it all off.
First question: Soda blasting seems like a good idea, any dangers, any special prep needed? Is it ok that quite a bit of the paint has been soaked with stripper?
I'm going to barrier coat the bottom. Any opinion of the Pettit product? I want to use it because the bottom paint I'm thinking about is a hard semi gloss Pettit product called Vivid/ It's supposed to be formulated for fresh water. So, any other options, ideas, should I just go ahead? Thanks,
Tony D

 

[Starman]

Soda blasting is the new wave of bottom stripping. It is less intrusive and environment friendly.

I takes more time to soda blast than to sand blast.

I spoke with a person about doing Boss Lady, but instead opted to have the bottom sand blasted, because we needed to see all the loose gel coat and blisters. Sand blasting will chip out all the small get coat bad spots.

Either way, I think it is money well spent. Your time , materials and the pure nasty of removing bottom paint has to be one of the worst jobs there is.

After soda blasting you may only have to touch up or sand a few areas and then start applying the new paint.

 

[Boatsb]

Sounds like a deal if you sand or soda blast it and get back to making progress. If you look at the time you put in and place a reasonable value on it you will see how much you spent on the long and winding road. Go the direct route and coat it with some west while your at it.

I would re think the paint though. Use a multiseason paint and use one color under and the second over. Run it on that paint until you see the under paint color and then use it about that much longer before you repaint. Buildup only slows the boat down.

 

[the kuz]

Two years ago a guy from Rock Hall MD used a planing machine to shave our hull. Took the mutiple layers of paint down so thin, you could see through the final (i.e. first coat) on the hull. Got all but a few small areas around the running gear and the inlets/through-hulls. Cost for our 36C was about $500. You might check into that process. Good luck.

Regards, Bob K

 

[ohiohatteras]

One warning....be prepared to spend on a bottom job!

I had mine corn shell blasted about 7 years ago...before soda blasting was big.....and the outcome was hundreds of popped blisters. Anyway..this transposed into a $4000 epoxy/barrier coat bottom job!

Also.....I can't sing enough praise for VC Offshore bottom paint. I'm up here with you on the Great Lakes and I am on season #7 with the original bottom paint job and still going strong! I've only had to touch up a couple spots where the hoist straps rubbed the paint off! It's well worth the money!

PM me if you would like to talk further...

Todd

 

[luckydave215]

At my next haul and paint I'll be stripping off the 3/16" or so of old paint, and I think I'm going to have the soda blast treatment.
Of course, since I'm not going to do the labor myself (you can't in California, environmental rules say you have to be licensed or something to work on antifouling paint) I'll do what my favorite yard wants to do. Chemical/soda blast/whatever. But if I get to choose......
I last painted in december, and the yard manager made the comment that there's probably a good 1~2 knots more speed in the boat without hauling around 6000 extra pounds of copper on the bottom. I bet he's right.

 

[thoward]

On my old boat there was a good 3/16-1/4" buildup of paint. I took a standard electric planer and knocked off the majority, then I used a grinder to get the rest. I do not think I will ever do it again. I had no idea just how bad that paint really was. The first day I got really sick and after that worked my tail off for several long days. It ended up taking about a week to get it sanded and painted. I can tell you by the time you buy all the grinding wheels, safety gear(full face chemical mask and coveralls), grinders(your grinder will be shot), sand paper, and misc other items you will come out ahead by having it blasted.

I have used the Interlux 2000 barrier coat and it worked ok. We have it on our Hatt and still have a blister here and there. You may want to check in to putting a hard bottom paint on for the first year and then add the soft of a different color after that. Then you can sand down to the hard after each season with out build up or messing up the barrier coat.

 

[jim rosenthal]

I would not shave the bottom under ANY circumstances. I would soda blast it, although there are other strippers which work better than the soy stuff, which got a so-so review in PBR. Soda blasting is safer than sand, and being spared the mess and trouble is well worth it.

I have had an Interlux Interprotect 2000 bottom on Blue Note, which I think is the same size hull as yours or close, for eight years. It's fine. Dave Sommers, who owns an identical boat to mine, used West System and did it himself. It is also fine. Both products are good. 3Ms vinylester system is also good. Essentially, it's more about the prep work and following directions exactly than anything else. The longer you dry the hull, the better it will all work. Good luck.

 

[SKYCHENEY]

I would soda blast and then use one of the proven barrier coats like Interprotect or West. Then I would use VC17. This is the perfect opportunity to start using VC. You need a clean, smooth bottom to use it and it will never build up on you. It is superb in fresh water and is so thin that you will use very little paint.

 

[ADaily3224]

Thanks for all the information.
I decided to do the soda after all, I really don't have time for any of the alternative methods, besides I hate getting covered with all that sticky bottom paint.

As far as the paint goes I can't decide. I have VC tar and VC offshore on my Boston Whaler Outrage, it's 5 years old and can't be told from new. I like it but am told it's a huge job doing it to a 36 foot boat. I know I'll be using either a white or light gray barrier coat. The Pettit is supposed to be a one coat hard bottom paint that doesn't need to be repainted until you can start to see the barrier showing through. After stripping about 12 square feet from the bow there appears to be no bottom damage and no blisters at all. The boat is out of the water from Oct. to June, and inside a heated building, so it should be nice and dry. The blasting is supposed to happen in the next day or so, I guess I'll have to make up my mind on the paint pretty soon. The Hatteras is docked in Lake Ontario all summer, the water stays pretty cold, there's almost nothing to clean off by the end of the summer. On the other hand the Whaler sits in Buffalo, Lake Erie and I'm cleaning the bottom of green slime a few times a season, the water is much warmer in Lake Erie. Thanks for all the input.

Tony D

 

[Maynard Rupp]

Tony, we did our '86 36 C three years ago. I had a guy chemiclly strip the bottom. We had so much bottom paint that he used 38 gallons of stripper. He does this all the time and uses the cheapest ACE hardware stripper. He has never had any problem with the gel-coat or glass cloth using this method. Nest he put visqueen around the boat and sanded the entire bottom with 36 grit using a dustless sander. Next I dug out and filled about 6 blisters and a patch of missing gell-coat with West Epoxy and their 404 filler. My son and I took over and rolled on 7 coats of Interprotect 2000. We did the entire Interprotect application in one day. The next morning we applied 2 coats of VC-17 bottom paint. This bottom has been absolutly perfect. We applied on new coat of VC-17 the next winter and another last month. Last season the boat spent 12 months in the water, 6 in fresh and 6 in salt water. When we pulled it it hardly needed a preassure wash. All you need to do to clean VC-17 is give it a good 20 knot run occasionally. Tony, I really think, as Sky said, that you have a perfect opportunity to make the switch to VC-17 because of your new barrier coated hull. You will never have to sand again, just wipe with a scotchbrite and re-coat annually. The whole process takes about 2 hours unless you are slow with tape. It wont peel or build up ever.

 

[ADaily3224]

Maynard, did you use the VC 17, the 18, or the offshore? Can you tell me how much you needed to do the two coats? I also thought you had to use the VC tar to get the proper adhesion?

Tony D

 

[Traveler 45C]

Maynard, where are you keeping the boat now?

Mine stays in Fl salt water all year and I’ve got a bottom job coming up soon.

 

[Maynard Rupp]

Maynard, did you use the VC 17, the 18, or the offshore? Can you tell me how much you needed to do the two coats? I also thought you had to use the VC tar to get the proper adhesion?

Tony D

Tony...VC-17 sticks to anything. No I don't use 18. That is just another vinyl bottom paint that builds up and someday has to be dealt with. I think we used 5 cans, (quarts), for the original application. Buy 6 and tell them you may want to return 1. Don't buy it in Canada. Their government only allows the cans with the blue plastic tops. You want the US stuff with the red plastic tops. The red top stuff has the new slime fighter. I would recommend the original color. It is a bright copper until about 2 weeks after launch, then it is a dark grey to black. The Blue looks just like the original in fresh water. It is never blue. In salt water it immedietly turns a bright blue. The red is sorta pink, so just use the original. The annual recoat takes 3 quarts

 

[Maynard Rupp]

Maynard, where are you keeping the boat now?

Mine stays in Fl salt water all year and I’ve got a bottom job coming up soon.

Unity is at Dinner Key Marina in Coconut Grove FL. Same place as Pascal's boat.

 

[ADaily3224]

We're under way now. The Blasters have been there for two days, they sid there was a lot of paint. I thought I did them a favor by removing a good portion with the Soy stripper, I guess not. That's now the hardest to remove. I hope the bottom is in good shape. I don't need another problem.

A couple pictures of the process. They use a giant bag similar to a vacuum cleaner bag to contain the soda and paint. When done they take the bag to a commercial Landry mat and throw it in the machine. The blasting material is Arm and Hammer Baking Soda, not the same for making a cake but similar.
Hopefully the pictures will show up on the site. I haven't had much luck in the past.

Tony D

 

[ADaily3224]

I have to try this again. I made the pictures too small. Let's see, double the size?

Tony D

 

[ADaily3224]

Bottom blasting is done. I have a few areas where I have to scrape a very small amount of paint, right near the boot stripe. Other than that it looks good. They went through the gel coat in a couple places. I guess the barrier coat will take care of that. The bottom is perfectly clean, it feels like Formica to the touch. It should hold paint very well.

Tony D

 

[jim rosenthal]

VERY nice. This is the way it ought to look. I wish this had been available when my boat was done, but it didn't exist then. You will get a great job out of this.

 

[yachtsmanbill]

Nice pics !! It looks like another job added to the to do list for me!! Mine looked like a moonscape, but not a single blister. Maybe I got lucky this time. ws