What Type Of Anti-foul Paint Works?

[Andrewcook]

As to the Fiberglass and Wooden Boats have been in the water laying ideal for some time this year. What sort of An-Foul Paint work's to keeping the Underneath reasonable in good state or does this means bringing forward for the Anti-Foul Paint to be done rather sooner then later? 

[BroadAmbition]

We do this process every two years with 'B.A', in all honesty it could probably be stretched longer but at two years it also gives us the opportunity to carry out any planking that maybe required and I would not be comfortable than going past our two year mark.

We use the paint range from Marine industrial at Worstead. 

After cleaning off & carrying out any repairs we use the Seajet 011 underwater primer followed by Seajet 037 coastal anti foul,  The boot topping is a  'Self polishing'  034 Emperor.  Works for us, we have been using these products since 2006 and are more than happy with them

Griff

[JennyMorgan]

Hempel Broads does the job perfectly well and it's made for the job.. Wait until after Christmas and Jeckells bulk buy and usually do it well cheap! I re-coat every two years but I suspect it might last three. Also available from Nearest & Dearest. Apply with a roller, easy, job soon done!

https://www.norfolkmarine.co.uk/broads-a-f-2-5-ltr-black-configurable-1020162

[marshman]

Tar varnish or to honest nothing. All you get is thick slime although if you have a shallowish mooring, then zebra mussels can be a pain. But they don't like shovels - so a quick lift every couple of years and a shovel soon sort them out.

What I never understand, is that every autumn they sell posh antifreeze to not harm the fish, yet people still slap on antifouling - thats just as poisonous and is it really necessary? OK in saltwater - rubbish takes just a few weeks to grow but on the Broads? Not really!!

[ChrisB]

https://www.marinesuperstore.com/antifouling-paint-guide

 

This is one of the best guides I have seen.

[MauriceMynah]

To be honest, I've washed boats more often that I've antifouled them, or to put it another way, I've never antifouled a boat! never seen the point. ... Oh and yes, I have washed a boat... back in 97 IIRC

[Smoggy]

17 minutes ago, MauriceMynah said:

To be honest, I've washed boats more often that I've antifouled them, or to put it another way, I've never antifouled a boat! never seen the point. ... Oh and yes, I have washed a boat... back in 97 IIRC

Would it be easier to antifoul the topsides MM?

[marshman]

Whilst its an interesting video I have NEVER used a primer between different antifoulings and never spotted the difference!

Anyhow thats by the by, this is freshwater and we do not suffer anything like growth seen in the sea - except for zebra mussels and they are usually overcome by a bit more throttle if it bothers you!

Don't forget though its poison you are putting back into the rivers!!!!

[MauriceMynah]

I would imagine that 24 hrs moored at the Berney Arms would see off any Zebra mussels !

[JennyMorgan]

Tar varnish works well, cheap as chips, but nasty stuff when it comes to sanding it smooth and it's really horrid to remove.

[BrundallNavy]

3 hours ago, JennyMorgan said:

Tar varnish works well, cheap as chips, but nasty stuff when it comes to sanding it smooth and it's really horrid to remove.

Modern tar varnish is like dish water next to useless. I use bitumen which is much thicker. 

[Oddfellow]

The only GRP hulls I would attack with tar varnish are ones that are in bad nick to start with. 

Anti-fouling provides an important layer of protection to your GEL coat. What most people don't understand is that Gel Coat and GRP are NOT waterproof. Constant immersion will cause osmosis in GEL which will go on to delaminate the GRP layers. The Antifoul provides a layer of protection between the wet stuff and the expensive to repair stuff. 

[Smoggy]

But antifoul is usually porous surely so no real water barrier.

[marshman]

Blimey - there must be hundreds of Broads boats with very bad osmosis then. I was never aware it was supposed to act as a waterproof barrier!!

However I should know better than argue with AB!

[Turnoar]

International VC Tar on a new hull might help in the battle against fibreglass madness / resomania (or osmosis to the man in the dyke). I have seen a hullsute example on the broads once after it had been left in for years, guessing at least ten or fifteen though. I don’t think worms mind old fashioned tar on a wooden boat!

[MauriceMynah]

33 minutes ago, Turnoar said:

(or osmosis to the man in the dyke)

I don't think he'll be listening, he's having far too much fun.

[JennyMorgan]

2 hours ago, FreedomBoatingHols said:

The only GRP hulls I would attack with tar varnish are ones that are in bad nick to start with. 

Anti-fouling provides an important layer of protection to your GEL coat. What most people don't understand is that Gel Coat and GRP are NOT waterproof. Constant immersion will cause osmosis in GEL which will go on to delaminate the GRP layers. The Antifoul provides a layer of protection between the wet stuff and the expensive to repair stuff. 

That's a worrying comment as not too many hire yards appear to anti-foul the entire underwater hulls.

[JennyMorgan]

1 hour ago, marshman said:

there must be hundreds of Broads boats with very bad osmosis then.

Potentially thousands!

[BroadAmbition]

Tar varnish works well, cheap as chips, but nasty stuff when it comes to sanding it smooth and it's really horrid to remove.

Your telling me, we had to remove loads of the stuff from the bottom of 'B.A' during the restoration.  Needed to get it of so we could inspect the hull thoroughly.  The only way we found that works was hand scrapers and electric heat guns and gauntlets, still took an age though

Griff

[ChrisB]

The best protection against future osmosis is to spray the new hull below and three or four inches above the waterline with an Epoxy like International's "Gelshield". 

This should be done from new. If part of remedial action then the hull needs to be very dry, either by utilising a heat jacket or many months drying out. If the hull is not dry then you will seal in the problem making it worse.

Osmosis starts the moment the boat is placed in the water, by the time you get a visual indication ie "Blistering" your osmosis is in an advanced stage.

During my time with Courtaulds Coatings who owned the "International" Brand prior to Akzo-Nobel (the latter pay my pension) we never made any claim that antifoul provided any protection other than stopping harmful organisms adhering to the hull.

One thing that is rarely mentioned or written about is "Chemical Blistering" on the hull. This is caused by overcoating antifoul with a non compatible one, hence the need for removal of old antifoul or application of a sealing primer. This type of chemical reaction is often mistaken for osmosis by yards. 

I have never understood why more builders do not offer to spray the hull from new with Epoxy. This would effectively stop what we used to refer to as " Accelerated Osmosis". For many years I moored at a yard up the River Frome near Wareham which was infamous for accelerated osmosis. 

The senario is a good quality boat, well layed up that has been kept in salt water. The hull over the years has taken up this salt water with no problems when lifted. When sold on it has passed inspection with flying colours. The trouble starts when when the new owner decides to moor her in predominantly fresh water, like up The Thames, Brundall or Ridge Wharf where I was. What happens now is "True Osmosis" the fresh water passes through the gel coat to neutralise the saline already in the hull. I have seen perfect hulls turn to having terrible boat pox in two or three years simply by moving a boat that has been in salt for a few years to fresh.

 

[Smoggy]

And if the bilge is constantly slopping with water it can come from inside as well especially with exposed glass fibres that can wick into the layup.

[JennyMorgan]

1 hour ago, Smoggy said:

And if the bilge is constantly slopping with water it can come from inside as well especially with exposed glass fibres that can wick into the layup.

Plus the dreaded polyester-mite, strewth, I'm going back to wood before the bottom drops out!

 

[MauriceMynah]

2 hours ago, Smoggy said:

And if the bilge is constantly slopping with water it can come from inside as well especially with exposed glass fibres that can wick into the layup.

good point. Which antifoul should I use to protect against that?

[JanetAnne]

2 minutes ago, MauriceMynah said:

good point. Which antifoul should I use to protect against that?

I believe a bottle of single malt poured into the keel followed by a trip across Breydon will suffice.  Sadly the single malt is rendered ineffective if filtered through the crew first  

[MauriceMynah]

The boat can rot!