so im chasing my bottom paint around with a scraper. I started by removing what I thought was a few lose sections. some of it comes off really easy but then theres bits that are still stuck on quite well. however after spending all day getting about 1/6 of the hull clean im over it and my schedule didn't account for me having to bring the hull back bare.

so what is my best option

1: suck it up and take all the anti foul off. at least I know that the new bottmom paint will stick and its got to be done sooner or later anyway

2: scrap off the really lose stuff and then just slap some new paint over the top not using a primer so that next year when I haul out I can easly remove the paint and do it properly

3: scrape off the lose stuff and add primer on the bare bits then anti foul. adding the primer will make it much harder to clean the hull next year but its the only way that the paint want fall off for the next 12 months. in this case going to option one sound like a better choice.

some one going to answer Bubble

Best thing I done with my yachts was to soda blast (remove antifouling) and recoat with 2 coats of epoxy undercoat and 2 coats of Micron extra antifouling! Makes it so easy for future slipping just water blast clean and recoat....no sanding required!

The answer to this depends on what sort of boat and what construction. Is the antifouling hard or ablative? From your posting I'm guessing hard. If you stick with ablative then usually the surface is good to go after a good pressure clean. Touching up bare spots with a primer then antifoul. With a 'glass hull that's pretty much the routine. If its timber or steel you may need more preparation and extra coats of primer.

The size of the vessel is going to effect your routine as well. If its only about 30 feet then rubbing back with wet and dry to reduce the paint thickness and even it out would probably be more beneficial than scraping. If its a fibreglass yacht then ensure you round off the corners of the scraper!

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Ramona said..

The answer to this depends on what sort of boat and what construction. Is the antifouling hard or ablative? From your posting I'm guessing hard. If you stick with ablative then usually the surface is good to go after a good pressure clean. Touching up bare spots with a primer then antifoul. With a 'glass hull that's pretty much the routine. If its timber or steel you may need more preparation and extra coats of primer.

The size of the vessel is going to effect your routine as well. If its only about 30 feet then rubbing back with wet and dry to reduce the paint thickness and even it out would probably be more beneficial than scraping. If its a fibreglass yacht then ensure you round off the corners of the scraper!

its alabative. the issues is that some of the previous anti foul is delaminated. well a lot of it is delaminated. the delaminated parts are still stuck to the sound parts but if I get the scraper on it then it just falls off like butter leaving a jigsaw of harder well stuck pieces. now I presume that the delaminated parts will just fall off later when I repaint because it isn't a sound structure. the difficult part is that to get to the bad parts I often have to remove the good parts also.


I think there must be about 10 years of build up of old antifoul and number of primers inbetween antifoul and then lastly on top last seasons alabative.

I think that really I know the answer in that I have to remove the lot and start again, anything else is grasping at straws maybe.

the hull is fibreglass - 30ft full keel.

I have done it to both my yachts both with 20 years worth of Antifouling. There is only one answer to the problem you have if you want to correct it. Your sailing performance should increase by 1 knot and your work on the slip will be reduced in time and labour in the future.

My boat was in a similar state with anti foul peeling off in layers and rough as guts. I ended up forking out for a soda blast back to the glass. I now use a hard anti foul because the divers here won't clean down an ablative finish because it leaves a bloom in the water and they will get hammered for it. The other benefit of going back to the glass is you know the condition of the hull.

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southace said..

Best thing I done with my yachts was to soda blast (remove antifouling) and recoat with 2 coats of epoxy undercoat and 2 coats of Micron extra antifouling! Makes it so easy for future slipping just water blast clean and recoat....no sanding required!

Southace,
When you say epoxy undercoat I assume you are referring to Interprotect Epoxy Primer?
Does 2 coats give enough thickness to prevent Osmosis?
Was there much prep work required after the Soda Blast before you applied the epoxy?
Any tips for applying the epoxy?

I'm considering undertaken the same project next time I slip

Epoxy primer to my understanding is just giving the antifouling a compatible key coating to stick with.....also it will give you extra barrier protection from water ingression.....I guess it's like a roll on gelcoat replacement.
As for Soda blast It depends on the condition of the hull and the operator.....a boat with osmosis the lamantes will blast apart around the effected areas and will require grinding out and filling and fairing.
If its just a mater of removing old antifouling a good operator should be able to take it back to just the original gelcoat which in this instance the hull could be coated in just epoxy undercoat if no osmosis is exposed.

I got my timber yacht done in Brooklyn , NSW with the soda blast....it was just to take of the old 20 years worth of antifouling. It tuned into a nightmare as my father had coated the hull with a chlorinated rubber I think after the epoxy coats had been applied anyway the soda just bounced of the the rubber and made a huge mess to the hull.....I made a decision to put the boat on the truck unfinished and then had it blasted again when it arrived in the new destination..... I think it coast me about 4k just for the blasting !!

Rolling the clear epoxy on should always be tipped of with a brush to remove air bubbles and leave a smooth glossy finish.......a coarse sand between coats and a wipe with wax and grease remover is a must.

I will try to dig up some pics to post.


Sorry I also need to add both my yachts got at least 5 coats of epoxy resin and then followed by the "interprotect" or simular epoxy undercoat and then antifouling!

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southace said..

Epoxy primer to my understanding is just giving the antifouling a compatible key coating to stick with.....also it will give you extra barrier protection from water ingression.....I guess it's like a roll on gelcoat replacement.
As for Soda blast It depends on the condition of the hull and the operator.....a boat with osmosis the lamantes will blast apart around the effected areas and will require grinding out and filling and fairing.
If its just a mater of removing old antifouling a good operator should be able to take it back to just the original gelcoat which in this instance the hull could be coated in just epoxy undercoat if no osmosis is exposed.

I got my timber yacht done in Brooklyn , NSW with the soda blast....it was just to take of the old 20 years worth of antifouling. It tuned into a nightmare as my father had coated the hull with a chlorinated rubber I think after the epoxy coats had been applied anyway the soda just bounced of the the rubber and made a huge mess to the hull.....I made a decision to put the boat on the truck unfinished and then had it blasted again when it arrived in the new destination..... I think it coast me about 4k just for the blasting !!

Rolling the clear epoxy on should always be tipped of with a brush to remove air bubbles and leave a smooth glossy finish.......a coarse sand between coats and a wipe with wax and grease remover is a must.

I will try to dig up some pics to post.


Sorry I also need to add both my yachts got at least 5 coats of epoxy resin and then followed by the "interprotect" or simular epoxy undercoat and then antifouling!

Did you allow anytime after the soda blast for the hull to dry out?
In some situations I thought the epoxy could trap moisture in the laminate and give you problems in the future?
By the way, can you suggest a good soda blast operator?

so im still chipping away at the bottom paint but I need to start to think about the next stage. from what im reading a barrier coat is the go. interlux interprotect seems to be a good choice for the epoxy. from what im reading people seem to talk about interprotect 2000 and interprotect 3000. however in australia it just seems to be called interprotect and that's it.. is this the same stuff as the interprotect 2000?

what have other people used as a barrier coat?

I use Primicon and apply the antifoul over it. What sort of scraper are you using? Two handed pull scraper with the corners rounded off should have a 30 footer cleaned down in a couple of hours. I'm guessing its a Clansman.

This is one of the occasions when it might pay to employ a couple of local youths for the manual stuff.

Any of the aluminium based grey primers is all you need under the antifoul. Epoxy some people say locks in the moisture. Probably a good marketing tool. Older 'glass hulls that are not showing obvious signs of osmosis are not suddenly going to come down with it. Osmosis was caused by using poor quality resin and poor techniques in the 70's/80's, its not something you catch. All 'glass hulls take up water, it does not mean they have osmosis. Treat the underwater area of your yacht the same as you would a timber yacht. Select the antifouling you intend using and follow the directions on the can.

I use Altex No5.

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Ramona said..

I use Primicon and apply the antifoul over it. What sort of scraper are you using? Two handed pull scraper with the corners rounded off should have a 30 footer cleaned down in a couple of hours. I'm guessing its a Clansman.

This is one of the occasions when it might pay to employ a couple of local youths for the manual stuff.

Any of the aluminium based grey primers is all you need under the antifoul. Epoxy some people say locks in the moisture. Probably a good marketing tool. Older 'glass hulls that are not showing obvious signs of osmosis are not suddenly going to come down with it. Osmosis was caused by using poor quality resin and poor techniques in the 70's/80's, its not something you catch. All 'glass hulls take up water, it does not mean they have osmosis. Treat the underwater area of your yacht the same as you would a timber yacht. Select the antifouling you intend using and follow the directions on the can.

I use Altex No5.

ramona,

your advice is contrary to almost everything I have read. not to say you are wrong but considering im down to the bare gelcoat this is an opportunity to get this right and do an epoxy barrier coat if it has some advantage. yes if the hull is moist then don't add the barrier coat. but the work need to get to this point vs the coat seems to make sense to slap a few coats of epoxy to keep things water tight?


im using a power scraper. cheap $18 from masters. it worked pretty well. I was going to post a video of it in action when I get the chance.

I'm not selling anything!


If your gelcoat is fine, select the antifouling of choice and follow the directions on the can. Use the primer they mention in their paint system. I'm retired now but have spent an extra ordinary amount of time working under boats on slips. Correct antifouling over matching primer is all you need.

Ramona, can you buy the two handed pull scraper that you mention or do you make them up? I've never seen one.

Green shed does a half decent one, long timber(about 300mm long) & SS blade about $10-15

You can get away with slapping primer on the bare patches then antifoul over everything,
but its just delaying the correction til later.

Scrape it all back with the above mentioned scraper (dont forget extra blades) - should take 1 very tiring day.

Then 2 rolled on layers of epoxy waterproofing if the hull is old and you have doubts about the gelcoat.
Or if the boat has been developing blisters.

If boat is young or gelcoat and glass are ok, then primer and antifoul is all you'll need.

Altex #5 or Micron extra would be my choice if ablative.
I have just used micron 66 and feel its not significantly better for the price.
My mates altex #5 , 4 boats away significantly outperformed my micron 66.
Both he and I use our boats a similar amount.

Have fun scraping - we all have to do it eventually !!

this is the tool of choice for me. effort vs time



some times it was slicing through like butter. the video shows a medium hard part so its not the best example of it working. I have a pull scraper and it was a lot easier using the power scraper, although for the really hard parts the pull scraper was the only option.


they are on special at masters at thee moment. so I highly recommend everyone get one now for $18. Bunnings don't sell anything like it so this is the only option in AU that I could find . a multi tool will not work as it needs a hammer action. a few old salts saw me using it and where impressed enough to come up and ask where I got it from and how much it was.

m.masters.com.au/

only the flexable blade work. I bought two units as I snapped the first blade. both units had an issue with the blade that required me to grind it back a bit to make it lose and fit better. a nice lose fit means that it will get a better hammer action. the first unit I bought the spot welds on the blade broke and then the scraper snapped.

again if your going to be scraping bottom paint in the next few years I highly recommend you give this ago and buy it now as its on special.

so far I have tried
sanding random orbital
sanding by hand
sanding with belt sander
sanding with finishing sander
soda blasting with a dodgy gravity feed sandblaster
a variety of hand scrapers including pull scraper
paint stripper

http://www.ebay.com.au/itm/291113955145?ssPageName=STRK:MESINDXX:IT&_trksid=p3984.m1436.l2649
I was wondering about this unit above rather than the cheap gravity feed soda blaster Bubble
costs around $2000 for some one to soda blast a 30 ft hull

Well, well, well...We are at it again.
Last winter we started on my mates 42 footer which had hard anti-foul piled on layer by layer in the last ages, some places 6-8mm thick. He said we just do it where the thing is peeling off, then we realised the spots full of liquid - osmosis oh! - and cut the long story short, we had to re-do the whole hull down to the gel coat and... and spent three weeks on the hard stand. It came up pretty good after all that hard yakka.
If you want pictures and videos of the work done, send me a pm.
For professional advice, ring the company whos' product you are going to use and they should supply you with ample info about what to do and how.
We used International products and the rep came out few times to give us guidance. They were really good, l was impressed by their helpfulness.

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bubble7777 said..

this is the tool of choice for me. effort vs time

?rel=0

some times it was slicing through like butter. the video shows a medium hard part so its not the best example of it working. I have a pull scraper and it was a lot easier using the power scraper, although for the really hard parts the pull scraper was the only option.


they are on special at masters at thee moment. so I highly recommend everyone get one now for $18. Bunnings don't sell anything like it so this is the only option in AU that I could find . a multi tool will not work as it needs a hammer action. a few old salts saw me using it and where impressed enough to come up and ask where I got it from and how much it was.

m.masters.com.au/

only the flexable blade work. I bought two units as I snapped the first blade. both units had an issue with the blade that required me to grind it back a bit to make it lose and fit better. a nice lose fit means that it will get a better hammer action. the first unit I bought the spot welds on the blade broke and then the scraper snapped.

again if your going to be scraping bottom paint in the next few years I highly recommend you give this ago and buy it now as its on special.

so far I have tried
sanding random orbital
sanding by hand
sanding with belt sander
sanding with finishing sander
soda blasting with a dodgy gravity feed sandblaster
a variety of hand scrapers including pull scraper
paint stripper

Bought the last Masters paint scraper they had Ill try it out next week if the weather is kind to lift the boat out seeing you have one bubble you should come down and bring it with you you look like your really getting into it there

never again!.. im still sanding and getting the last bits off. I actually dug a hole below the keel so I could get under the keel. guy in the marina said he has never seen anyone do that before most people lift it onto the travel lift. I added that im doing 4 coasts of epoxy, a tie in coat and two coats of antifoul. I would need to be on the travel lift for 3 days which no one does. so I have no idea how other people do this if they don't dig a hole.

in other out of the box crazy ideas today because it's raining I decided to add 10 posts leaning on the rub rail and coverd the entire boat in glad wrap to keep the dust out and also keep the rain out. ill upload the picture when its better weather. I got a few funny looks when I ran 600 meters of glad wrap around the boat.

also after much research and ringing reps from company's I have decided the paint is going to be

3-4 coats of jotun jotacoat 605 two part epoxy
1 coat of jotun viniguard
2 coats of hempel anti foul


the jotacoat was in 4 litre cans for $100

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bubble7777 said..

also after much research and ringing reps from company's I have decided the paint is going to be

3-4 coats of jotun jotacoat 605 two part epoxy
1 coat of jotun viniguard
2 coats of hempel anti foul


the jotacoat was in 4 litre cans for $100

I would like a detail story when you have time later when its finished Bubble if you wouldn't mind. Next year Ill be doing the same thing

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bubble7777 said..

also after much research and ringing reps from company's I have decided the paint is going to be

3-4 coats of jotun jotacoat 605 two part epoxy
1 coat of jotun viniguard
2 coats of hempel anti foul


the jotacoat was in 4 litre cans for $100

I tried the Hempel antifoul and was not impressed. Why not use Jotun antifoul? I used Jotun for 20 years or so, it was what the fish coop stocked. Just ensure you get the right one. I use Altex No5 in red, I like their red. If your after blue or black Jotun is good. Shipwright that runs my local slip only stocks Jotun and Altex. I have half a tin of Hempel down stairs if any one wants it!

Bubble, could you tell me where you bought the paint? It sounds like you have done some good research.
I will be doing a hull renovation on a Clansman which is being trucked to my place the week after Easter. I will have a couple of months to give it a makeover before putting back in the water, including a refurb of the hull.

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Ramona said..

bubble7777 said..

also after much research and ringing reps from company's I have decided the paint is going to be

3-4 coats of jotun jotacoat 605 two part epoxy
1 coat of jotun viniguard
2 coats of hempel anti foul


the jotacoat was in 4 litre cans for $100

I tried the Hempel antifoul and was not impressed. Why not use Jotun antifoul? I used Jotun for 20 years or so, it was what the fish coop stocked. Just ensure you get the right one. I use Altex No5 in red, I like their red. If your after blue or black Jotun is good. Shipwright that runs my local slip only stocks Jotun and Altex. I have half a tin of Hempel down stairs if any one wants it!

I'm using hempel because for some unknown reason it works better than anything else I have seen in the Caboolture river. Everyone on the mooring is using jotun and my bottom stays cleaner . My theory of this is that hempel need a flow of water all the time more than other alabatives and the cab river provides that flow with the strong tidal movement . I agree that hempel being better makes no sense though. Last season may have been a freak occurance and ill have a more valid argument for it in another 18 months.

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Shotchas said..

Bubble, could you tell me where you bought the paint? It sounds like you have done some good research.
I will be doing a hull renovation on a Clansman which is being trucked to my place the week after Easter. I will have a couple of months to give it a makeover before putting back in the water, including a refurb of the hull.

I got the jotun from montys marina at beachmere and the antifoul came from bias boating . Good luck with your refurb of the hull

My mooring is in a strong tidal river as well. I used the Hemple semi hard which is still an ablative. Looked good for 3 months then rapidly deteriorated.

I purchased what looked to be the last two of those electric scrapers from masters in Northland Melbourne on Sunday, sure enough reduced to $18. Gave it a bash yesterday. They are really good at tearing through the antifoul and not damaging the undercoat, it was more effective where the antifoul was thicker, giving the scraper a better edge to get under. It wasn't a true test for the tool, as I was only using it on the crazed/brittle sections of antifoul.

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SirJman said..

I purchased what looked to be the last two of those electric scrapers from masters in Northland Melbourne on Sunday, sure enough reduced to $18. Gave it a bash yesterday. They are really good at tearing through the antifoul and not damaging the undercoat, it was more effective where the antifoul was thicker, giving the scraper a better edge to get under. It wasn't a true test for the tool, as I was only using it on the crazed/brittle sections of antifoul.

I think you better come around and give me a hand on my boat this weekend Sir J Man two of those plus mine will work wonders which side do you like the best Sir Jman port or starboard or port < can supply the beers