Advice needed re problem with 2pack blacking.

[JonesBoy]

In July 2015 I had the hull sand blasted and coated in 2 pack by a boat yard, expensive.

I have just had the boat removed from the water and pressure washed.

The hull coating is covered in blisters some of which have burst with the washing others are still intact. Under the ones that have burst the steel is clean and white.

 

Solutions?

I have contacted the paint manufacture and waiting a reply I will then contact the boat yard.

After that depending on replies? Any legal remedies, do I name the boat yard and or paint manufacture?

Any suggestion would be most appreciated.

[Alan de Enfield]

2 minutes ago, JonesBoy said:

Under the ones that have burst the steel is clean and white.

 

 

White or Silver ?

 

 

[blackrose]

Either the hull wasn't blasted properly; wasn't cleaned after blasting; the paint wasn't mixed properly according to the data sheet; it wasn't applied properly within specified layer thickness or it was applied at the wrong temperature; overcoating times weren't followed, or possibly the boat went back into the water too soon.

 

People tend to talk about two pack epoxy as if it's a generic paint. Do you know which two pack epoxy was used?

 

Edit: I've just realised it went in on 2015 so 6 years ago. Mine is also 6 years old and I'm hoping to get a few more before I need to recoat it. 6 years is ok but it still shouldn't be blistering.

Edited March 25, 2021 by blackrose

[Phoenix_V]

I had this problem a few years ago, the suspected cause was moisture trapped under the paint during application, we popped the blisters, touched up and it was good for several more years, any silvering would suggest electrolytic corrosion, check the anodes and wiring.

[Alan de Enfield]

7 minutes ago, Phoenix_V said:

......... any silvering would suggest electrolytic corrosion,...................

 

MIC produces silver 'pits' in the paint

 

Even a grain of sand left after sand-blasting can cause the problem :

 

Extract from a 18 page document on how corrosion happens in Fresh Water

 

The oxygen concentration cell may be initiated by anything that will shield a small area from the dissolved oxygen in the water, such as a grain of sand or a microbial colony

 

 

 

[dmr]

If this was a top job done in a heated workshop with "scientific" type monitoring etc then you might have a case, but if it was just done in a drydock then making some repairs after 6 years is to be expected.

 

Two pack is (in my opinion) oversold as a magic coating that lasts ten years with no maintenance, in reality its just a paint that is much much better than ordinary blacking but it will need periodic repairs and overcoating.

 

...................Dave

[jonesthenuke]

Did you watch the coating being applied, there may be clues for the degradation? For example, how soon was the coating applied after blasting (it should be immediate so that no surface rusting starts). What was the surface condition? What was the temperature (of the steel and ambient).

 

I have seen vlogs of people showing their boat being 2 packed and the application was less that ideal.

[JonesBoy]

Thanks for replies

Under the blisters the steel is white the same colour as when blasted.

There is no orange coloured growth and no pits.

The boat yard state they apply the coatings in line with the manufactures data sheets.

2 pack was by a well know company and on first response said “Should give many more years trouble free than you’ve experienced” the boat yard is supposed to be highly rated, we will see.

I expect scratches etc. but this blistering is all over the hull. The boat has an isolating transformer installed along with anodes.

Perhaps I expect too much from an expensive process and a job to be done well.

[dmr]

54 minutes ago, JonesBoy said:

Thanks for replies

Under the blisters the steel is white the same colour as when blasted.

There is no orange coloured growth and no pits.

The boat yard state they apply the coatings in line with the manufactures data sheets.

2 pack was by a well know company and on first response said “Should give many more years trouble free than you’ve experienced” the boat yard is supposed to be highly rated, we will see.

I expect scratches etc. but this blistering is all over the hull. The boat has an isolating transformer installed along with anodes.

Perhaps I expect too much from an expensive process and a job to be done well.

 

Can you post some photos? are these blisters fully all over the boat or in localised patches, how many blisters per square foot?

Are you sure the boat really was shot blasted...did you see it after blasting and before painting?  Was it done indoors or outdoors?

I assume the epoxy went directly onto bare steel without using Vactan or anything daft like that?

 

Which epoxy was used?   You can tell us because the problem is almost certainly down to preparation/application rather than the epoxy?

 

............Dave

[David Mack]

Did you get any sort of 6 year plus  guarantee from the boatyard that did the work?  If not I would suggest that the legal route would be a sure fire way of losing more cash with no chance of success.

[JonesBoy]

Thanks DMR

Some pictures of hull.

According to the boat yard where the boat is at present the blisters are widespread all over the hull.

The boat was indeed shot blasted indoors and epoxy went directly on to bare steel.

A further assessment is to be made on Monday re work require for a fix.

Due to lockdown I am unable to visit boat myself so current info is from marina doing the inspection.

 

David Mack

Thanks for replying.

If 2 pack epoxy just lasts this long then I have obviously wasted the cost and should have slapped bog standard blacking on. You live and learn thinking you get what you pay for.

Just pissed off at the moment.

[Alan de Enfield]

 

Strange, that looks like lack of adhesion, but what is weird is that it is all circular, no 'sheets' or 'strips' coming off, there is a clean (almost cookie cutter) hole and you can see the depth of the paint thickness.

 

 

 

[Richard10002]

49 minutes ago, JonesBoy said:

Thanks DMR

Some pictures of hull.

According to the boat yard where the boat is at present the blisters are widespread all over the hull.

The boat was indeed shot blasted indoors and epoxy went directly on to bare steel.

A further assessment is to be made on Monday re work require for a fix.

Due to lockdown I am unable to visit boat myself so current info is from marina doing the inspection.

 

David Mack

Thanks for replying.

If 2 pack epoxy just lasts this long then I have obviously wasted the cost and should have slapped bog standard blacking on. You live and learn thinking you get what you pay for.

Just pissed off at the moment.

 

 

if that was big standard blacking, you would just give it a bit of a sand/wire brush, to get a key, and apply some more to cover it.

 

Is it different with epoxy.

 

If the solution is to remove it all and start again, I’d say the risks involved in epoxy outweigh the benefits, and I’d rather slap on some standard blacking every 2 or 3 years. Particularly when a boat ought to be lifted at least every 3 or 4 years in order to inspect the bottom, so no big deal to slap on some blacking at the same time.

 

When you hear some of the stories about hull covering, employing somebody to do such a critical job seems to be very risky.

[David Mack]

How many coats of epoxy went on? The damage looks like it could be air bubbles in the coating, but I expect that to be more of an issue with a single coat than the 2-3 that would normally be applied.

[David Mack]

58 minutes ago, JonesBoy said:

 

Presumably that was taken when the epoxy was being applied.

Good that the details around the strakes and chine were brushed first, but I do wonder why the person brushing along the top and bottom of each strake didn't do the whole strake as well. This is where damage is most likely to occur and the extra coat would be beneficial for minimal extra work. Makes you wonder how well the rest of the job was done.

How was the rest of the epoxy applied? Brush? Roller? Spray?

[dmr]

1 hour ago, David Mack said:

Presumably that was taken when the epoxy was being applied.

Good that the details around the strakes and chine were brushed first, but I do wonder why the person brushing along the top and bottom of each strake didn't do the whole strake as well. This is where damage is most likely to occur and the extra coat would be beneficial for minimal extra work. Makes you wonder how well the rest of the job was done.

How was the rest of the epoxy applied? Brush? Roller? Spray?

 

The epoxy will get scraped off the strakes quite quickly so not really much point in giving them an extra coat. The painter has decided to pay attention to all of the welds which is not really essential but not a bad idea. Maybe work epoxy nicely into the welds with a good small brush then use a much bigger brush for the rest of the boat?

[JonesBoy]

Yes all looks strange, the circles are the ones that popped when pressure washed more are still intact.

According to the spec given to me 2 coats were applied by airless spray to a thickness of 300 to 400 microns.

The picture is of the prep work before full spray.

Anyway that’s all the info for now hopefully more on Monday, if paint manufacturer and boat yard get back to me.

So going into a dark corner and have a good cry. ?

Thanks for all your input.

 

[dmr]

The round holes and "unpopped" bubbles are wrong, but I don't know why. However if you have used the boat quite a bit then things are really not too bad. There is evidence of scraping as might be expected. The good news is that the epoxy appears to have protected the hull very well and prior to the pressure washing I suspect the epoxy was good and so the hull had suffered No rusting and any previous pitting has not progresses.

 

All those round holes need attention with a wire cup brush or similar, the whole hull then needs abrading to provide a key on the epoxy surface, and then two new coats of epoxy over the whole lot..  Do the same again in maybe 4 years time.

 

The bubble things are unfortunate but the scraping is almost inevitable and remedial work every 3 or 4 years is wise, but the important thing is that the epoxy has provided very good protection for 6 years.

 

If you paid maybe £3000 for the shot blast and epoxy then you should be satisfied, if you paid more like £6000 then the yard did not do a £6000 job and you should be asking for them to bear much of the cost of this docking (they will likely refuse but you should ask ?).

 

...............Dave

[Midnight]

I have used 2-pack since the boat was new but I wouldn't expect it to last 6 years without blistering. I once left it 5 years but the water line looked similar to the pictures above so now I usually re-paint every two years. That's probably over-kill as I find it's really only the odd scrape that needs to be done., but I wouldn't consider going beyond 3 years. As I get my paint from a shipping industry supplier and being a member of a boat club with a dry dock the overall costs are probably a lot less than most have to pay for lift-out and blacking.

Edited March 26, 2021 by Midnight

[JonesBoy]

DMR. Thanks for reassuring comments.

 

Midnight. Thanks for info. No access to those type of facilities + getting a bit old to do myself.

Hate painting as the wife know too well.?

 

It would seem all the hype regarding 2 pack epoxy does not stand up. It would have been perhaps more cost effective to have standard blacking done every 2 years. This would have giving me a longer time span than this current coating.

What they say about boats, bring out another thousand!!

[dmr]

14 minutes ago, JonesBoy said:

DMR. Thanks for reassuring comments.

 

Midnight. Thanks for info. No access to those type of facilities + getting a bit old to do myself.

Hate painting as the wife know too well.?

 

It would seem all the hype regarding 2 pack epoxy does not stand up. It would have been perhaps more cost effective to have standard blacking done every 2 years. This would have giving me a longer time span than this current coating.

What they say about boats, bring out another thousand!!

 

In a few cases epoxy does appear to last for ten years withut attention, but in most cases will need remedial work every three or four years, no epoxy will cope with getting scraped against protruding lock gate collars etc. A boat really should come out of the water for inspection every three or four years regardless of how it is painted.

 

Over a period of many years I suspect epoxy works out a bit more expensive than ordinary blacking, but it protects the boat much much better which is cost effective in the longer term.

 

...................Dave

[Phoenix_V]

the blisters look like the ones we had which we ascribed to moisture trapped behind the paint, it doesn't need blasting again as dmr said just deal with any new rust where the blisters have been popped, touch up those spots sand and a coat of epoxy all over, it would have looked worse if you had used ordinary blacking and will not cost much more to use epoxy again .

[cuthound]

My boat was zingered and epoxy blacked from new.

 

When I bought it at 7 years old, the surveyor commented on the excellent condition of the blacking, once he had pressure washed off the mussels!

 

After a further 3 years I had it docked, and the boatyard called me to come and inspect it after the pressure washing. They showed me that it was still in excellent condition except for a few scrapes, so they touched these up and told me to check it again in a further 2 years.

 

I finally had it blacked in 2019, whe  it had been on for 12 years.

 

The original blacking was International Interzone 954, so I requested this again when I had it blacked.

Edited March 27, 2021 by cuthound
Phat phingers

[Phoenix_V]

On 27/03/2021 at 13:32, cuthound said:

 

I finally had it blacked in 2019, whe  it had been on for 12 years.

 

 

just curious was that treating the bad patches and one recoat or blast back to bare metal (or  zinger?) and complete repaint (how many coats) if blasted does it cost more to remove epoxy/zingering than bitumen thanks in anticipation

[cuthound]

1 hour ago, Phoenix_V said:

just curious was that treating the bad patches and one recoat or blast back to bare metal (or  zinger?) and complete repaint (how many coats) if blasted does it cost more to remove epoxy/zingering than bitumen thanks in anticipation

 

Treating the bare patches (mainly on the stem post) and two coats of 2 pack blacking.

 

No need to remove any 2 pack still firmly fixed.

 

I wouldn't think it would cost more to remove 2 pack by grit blasting, with or without Zinger than it would to remove bitumen. The cost is mainly labour and grit used.