Blistered roof paintwork

[melkaren]

Have any folk here experienced blistered paintwork recently.....our new boat was painted this July using Craftmaster paints all round....however the roof paint work has broken out in blisters along its entire length...mainly small ones, 1-2mm but where items have been placed on the roof they are 4-5mm and many have burst showing the primer underneath...

 

The paint used was the Craftmaster ANTI-SLIP DECK ENAMEL with corresponding primer and undercoat, colour was off white...

 

I have obviously spoken to the painter about the matter and its repaint is being arranged..

 

Would be interested in hearing from others who have suffered same problem

[dave moore]

Hi

Doubtless Phil will want to add to this, it sounds to me like microblistering. The culprit is usually moisture on the surface as paint is applied..perhaps condensation not totally removed or ambient damp in cold conditions...tho' a July job wouldn't suggest this. Can I make a plea to avoid long term roof storage, which often exacerbates this problem....planters, coiled ropes and the like are all potential culprits. Most paint systems will fail if continuously damp, in my experience.

Cheers

Dave

[melkaren]

Thanks for that Dave...all items now removed from roof...

 

Boat painted indoors BTW

 

Mel

[PaddingtonBear]

Indoors does not make much difference, condensation is caused by warm, moist air condensing on a colder surface. It is likely to be somewhat worse indoors in fact as there will be no breeze. It is usually made even worse by the use of heaters - best results are achieved in gentle conditions, not to hot or cold and as Dave has said not damp. When I painted Warrior I did it in an open sided floating paint dock in the early summer, and getting up around 0530 to paint before it got too hot as paint must not dry too quickly either.

[Nickhlx]

I wonder if we have the same problem brewing as well - it's also the roof, Craftmaster paint rings a bell and it's anti-slip too... blisters are 1-2mm - also sounds very similar - Boat was painted in around Feb - March this year and even the colour is similar being cream... from memory the hull / shell was a green base paint layer over the bare metal, presumably to protect it between hull manufacturer and builder, who then painted it with the various layers. Presumably the cost of remedial work will be down to the builder being only about 9 months old ? I would prefer the job is delayed until the weather is a lot warmer to avoid condensation issues messing up the re-paint work... what would painters recommend would be the best time to do it ?

 

Thanks,

 

Nick

[Albion]

Hi

Doubtless Phil will want to add to this, it sounds to me like microblistering. The culprit is usually moisture on the surface as paint is applied..perhaps condensation not totally removed or ambient damp in cold conditions...tho' a July job wouldn't suggest this. Can I make a plea to avoid long term roof storage, which often exacerbates this problem....planters, coiled ropes and the like are all potential culprits. Most paint systems will fail if continuously damp, in my experience.

Cheers

Dave

 

I tend to agree with you Dave but I'm not sure that any month this year could be relied upon to be particularly humidity free

I'm guessing that those with heated dock facilities have had a better time of it this year.

Microblistering due to close contact of roof stored items, and even cratch covers and the like, will occur even on the best paint jobs and it seems to help if the surfaces can be left to air occasionally.

Roger

[Richard Cracknell]

the best boat painter in the country used hammerite floor paint on our narrowboat roof, excellent job, lovely colour too

 

I tend to agree with you Dave but I'm not sure that any month this year could be relied upon to be particularly humidity free

I'm guessing that those with heated dock facilities have had a better time of it this year.

Microblistering due to close contact of roof stored items, and even cratch covers and the like, will occur even on the best paint jobs and it seems to help if the surfaces can be left to air occasionally.

Roger

 

 

the best boatpainter in the country used hammerite floor paint on our narrowboat roof, excellent job, nice colour too

Edited December 13, 2009 by Richard Cracknell

[Phil Speight]

the best boat painter in the country used hammerite floor paint on our narrowboat roof, excellent job, lovely colour too

 

 

 

 

the best boatpainter in the country used hammerite floor paint on our narrowboat roof, excellent job, nice colour too

 

I wonder who the best boat painter in the country is !

 

We at Craftmastr have had no complaints about our anti-slip Deck Enamel blistering. Our contact details are on every tin and we are happy , and very keen, to discuss technical problems with customers.

It sounds very much like micro-blistering. This is caused in two ways.

 

1) By solvent retention when paint has been applied in too high a temperature. In this case the surface paint dries so quickly that solvents are trapped underneath. They are then drawn to the surface causing blisters.The same can happen if a paint dock has insufficient high level ventilation. Solvents that have evaporated but not been able to dissipate can cause a solvent saturated atmosphere.

 

2) By moisture trapped under the paint. This could have been absorbed into primer left exposed for too long ( often a problem with "sailaways" ), or, to a lesser degree by undercoat not being glossed over soon enough, or by condensation in the atmosphere during painting.

 

3)There isn`t a 3.

 

None of the above are paint related problems and can happen whatever manufacturer`s product is used. If the customers in question had contacted us directly , I would have been happy to explain all the above , the ways of assessing which problem you`ve got and what is best to be done about it .

 

Please - give ALL the paint manufacturers sufficient respect to contact them about things like this.

You may surprised how helpful we can be GIVEN CHANCE.

Phil

Edited December 14, 2009 by Phil Speight

[Phil Speight]

I wonder who the best boat painter in the country is !

 

We at Craftmastr have had no complaints about our anti-slip Deck Enamel blistering. Our contact details are on every tin and we are happy , and very keen, to discuss technical problems with customers.

It sounds very much like micro-blistering. This is caused in two ways.

 

1) By solvent retention when paint has been applied in too high a temperature. In this case the surface paint dries so quickly that solvents are trapped underneath. They are then drawn to the surface causing blisters.The same can happen if a paint dock has insufficient high level ventilation. Solvents that have evaporated but not been able to dissipate can cause a solvent saturated atmosphere.

 

2) By moisture trapped under the paint. This could have been absorbed into primer left exposed for too long ( often a problem with "sailaways" ), or, to a lesser degree by undercoat not being glossed over soon enough, or by condensation in the atmosphere during painting.

 

3)There isn`t a 3.

 

None of the above are paint related problems and can happen whatever manufacturer`s product is used. If the customers in question had contacted us directly , I would have been happy to explain all the above , the ways of assessing which problem you`ve got and what is best to be done about it .

 

Please - give ALL the paint manufacturers sufficient respect to contact them about things like this.

You may surprised how helpful we can be GIVEN CHANCE.

Phil

Was wrong there is a 3). I forgot. If a painter chooses to clean either synthetic primer or undercoat with a solvent based de-greaser ( or white spirit ) some of that can be immediately absorbed before it has time to flash off. This will also cause solvent retention and , ultimately, micro-blisters.

Phil

Edited December 15, 2009 by Phil Speight

[David Schweizer]

Was wrong there is a 3). I forgot. If a painter chooses to clean either synthetic primer or undercoat with a solvent based de-greaser ( or white spirit ) some of that can be immediately absorbed before it has time to flash off. This will also cause solvent retention and , ultimately, micro-blisters.

Phil

Your number 3 has potentially explained the tiny blisters which appeared in my roof about a year after I painted it (well part of it !).

 

If these have appeared because of solvent retention, would it be OK to flat it off, and apply a couple more top coats, or do I have to go back to the metal again? Remember we are talking about a boat that is nearly 30 years old which will would not fetch a great deal more than it's basic value, even if your dock did a full paint job on it.

[mikevye]

the best boat painter in the country used hammerite floor paint on our narrowboat roof, excellent job, lovely colour too

 

Bit of a sweeping statement there. I'm actually the best painter in the world, problem is it's my opinion and nobody else thinks so!!!

[Phil Speight]

Was wrong there is a 3). I forgot. If a painter chooses to clean either synthetic primer or undercoat with a solvent based de-greaser ( or white spirit ) some of that can be immediately absorbed before it has time to flash off. This will also cause solvent retention and , ultimately, micro-blisters.

Phil

My last comment on this issue. As many of you who have dealt with me know I would usually by now have posted various tests and remedies for the problem. The reason I haven`t is that , for some unfathomable reason, the original poster`s use of capital letters ( as in CRAFTMASTER etc )

annoyed me.

So;if you have a problem with micro-blistering ( whatever the paint ) please PM me and I`ll do what I can to help. As always.

Phil

[Phil Speight]

My last comment on this issue. As many of you who have dealt with me know I would usually by now have posted various tests and remedies for the problem. The reason I haven`t is that , for some unfathomable reason, the original poster`s use of capital letters ( as in CRAFTMASTER etc )

annoyed me.

So;if you have a problem with micro-blistering ( whatever the paint ) please PM me and I`ll do what I can to help. As always.

Phil

Ok - not quite my last comment. The original poster has contacted me and I now accept his reason for the capital letters - so I`m sorry I got grumpy. He asked some pertinent questions and I have answered them .

Phil

[Kraken]

Was wrong there is a 3). I forgot. If a painter chooses to clean either synthetic primer or undercoat with a solvent based de-greaser ( or white spirit ) some of that can be immediately absorbed before it has time to flash off. This will also cause solvent retention and , ultimately, micro-blisters.

Phil

 

 

Hi Phil,

 

What do you use instead of a solvent based de-greaser?

[Phil Speight]

Hi Phil,

We don`t. Once a boat has been linished to bright metal we use tack cloths to clean dust off right through the rest of the job. We avoid any contaminants thereafter - right down to sweaty palm prints!

Cheers

Phil

What do you use instead of a solvent based de-greaser?

We don`t. Once the boat has been linished to bright metal we avoid all contaminants - even sweaty palm prints. We use tack cloths to remove dust thereafter.

Cheers

Phil

ps - pushed the wrong bit - hence the double reply !

Edited December 16, 2009 by Phil Speight

[boaterphil]

We don`t. Once the boat has been linished to bright metal we avoid all contaminants - even sweaty palm prints. We use tack cloths to remove dust thereafter.

Cheers

Phil

ps - pushed the wrong bit - hence the double reply !

Having repainted my boat last year, the first repaint after being built 9 years ago, I repainted with toplac which is what we used originally, the colour retenttion was pretty good, it failed because, the original painter used thinners, and it caused the red to go milky, Ialso had some micro blistering which at the time was put down to mill scale, this problem came after 4 years i rubbed them out and repainted the roof and no problems whatsoever, I have used thinners to clean the mettle work, applied undercoat for it then to blister, I was advised not to use thinners as it it did blister stright away!! Craftmaster are on the defensive, my neighbour used there paint and is had far gloss retention, than toplac. I had my boat lifted at the same time as having it repainted and was delighted to find the Comastic in perfect condition after 3 years UNDER the waterline I put on 4 coats the last time and applied another 4 coats, but do not apply over black tar varnish, as it may react and not go off,

[buggsy]

We don`t. Once the boat has been linished to bright metal we avoid all contaminants - even sweaty palm prints. We use tack cloths to remove dust thereafter.

Cheers

Phil

ps - pushed the wrong bit - hence the double reply !

 

Sometimes i bloody wonder why i dont listen to people that are in the know. I visited Phil's paint dock and watched John painting and he told me exactly the same only tack cloth. I work with automotive paint and we produce solvent panel wipes so i thought i would use these as well tack cloths. How wrong am i , during this cold snap i have noticed microblistering on my roof and on some small areas luckily not on the main panels. For the record i found the Craftmaster paint excellent and the advice from Phil and John excellent. So the moral of the story is follow the advice that you are given.

 

Steve

[starman]

Was wrong there is a 3). I forgot. If a painter chooses to clean either synthetic primer or undercoat with a solvent based de-greaser ( or white spirit ) some of that can be immediately absorbed before it has time to flash off. This will also cause solvent retention and , ultimately, micro-blisters.

Phil

 

Just resurrected this post so I can ask what exactly is a 'solvent based degreaser'? Would that include liquid Panel Wipe or is that just the active constuent of tack cloths?

[wrigglefingers]

Just resurrected this post so I can ask what exactly is a 'solvent based degreaser'? Would that include liquid Panel Wipe or is that just the active constuent of tack cloths?

 

Hello Kevin, I've never seen John ever use Panel Wipe so I would assume - as I don't exactly know - that it contains solvent. John is meticulous in his preparation but doubly so when the boat is down to bare metal. I can ask him for you but he's on holiday for the next few days and so not at Dadford's or indeed on the end of a telephone. Dunno if that helps, but he's the man to ask.

[Bob18]

Tack cloths are designed to pick up dust of the surface, without leaving anything behind. Most of the time they work well enough.

Panel wipe is a solvent (in the good old days thinners) on a cloth that is intended to get rid of grease from the surface you are about to paint, trouble is that all too often all it does is spread the grease around in a thinner film.

[GSer]

I know you can buy tack cloths, but are there any little tricks that can be used to make your own?

[wrigglefingers]

I know you can buy tack cloths, but are there any little tricks that can be used to make your own?

 

I'm sure there are but they're so cheap I'd really not think it'd be worth the bother - the muslin used is quite expensive and I can't source the unsticky fabric for any less than the price you pay for the tack cloths complete with the sticky stuff. I would assume it's a gum of some description but clearly not an oil-based one. When I was painting Cobbett, I probably used about thirty in total for the inside of the entire boat which cost me the princely sum of constant supply of cake and biscuits. Even so, buying them at Brewer's isn't horrific compared to the cost of the paint and the brushes.

Edited November 8, 2011 by wrigglefingers

[melkaren]

As the original poster of this topic I would like to update the forum on the subsequent saga of our boat roof....

 

The initial blistered paintwork was completely removed in October 2010, taken back to the metal and then re-painted with six coats of primer, undercoat and topcoat...this was done indoors and boat out of the water..within 2 weeks the paint re-blistered, but not micro blisters, it blistered like the ones you get on your heels from a bad pair of fitting boots...the painter was unhelpful in the extreme and never put the problem right, but that's another story...

 

I subsequently discovered the process had involved 'panel wipes' that are normally found in the car industry, now I am no paint guru or scientist...but did wonder if that was the cause, if you burst one of the blisters it emitted an acetic acid smell...

 

Now thoroughly pissed off with 'professional' boat painters I took the stance of if you want a job doing right, do it yourself.... so I removed the offending paintwork, de-greased with white spirit from B & Q, and painted the roof myself using a well known brand of exterior metal paint (no not Hammerite), I did it outdoors, got the odd fly stuck, but they do break off at the ankles when paint is dry...and did it as scientifically as reading the instructions on the tin...total cost was £300..this was done in May, it still looks excellent...although I am blowing my own trumpet, it has now lasted far longer than both the pro jobs it has previously had...

Edited November 8, 2011 by melkaren

[Phoenix_V]

As the original poster of this topic I would like to update the forum on the subsequent saga of our boat roof....

 

and painted the roof myself using a well known brand of exterior metal paint (no not Hammerite),

Do tell, which one

[Phil Speight]

As the original poster of this topic I would like to update the forum on the subsequent saga of our boat roof....

 

The initial blistered paintwork was completely removed in October 2010, taken back to the metal and then re-painted with six coats of primer, undercoat and topcoat...this was done indoors and boat out of the water..within 2 weeks the paint re-blistered, but not micro blisters, it blistered like the ones you get on your heels from a bad pair of fitting boots...the painter was unhelpful in the extreme and never put the problem right, but that's another story...

 

I subsequently discovered the process had involved 'panel wipes' that are normally found in the car industry, now I am no paint guru or scientist...but did wonder if that was the cause, if you burst one of the blisters it emitted an acetic acid smell...

 

Now thoroughly pissed off with 'professional' boat painters I took the stance of if you want a job doing right, do it yourself.... so I removed the offending paintwork, de-greased with white spirit from B & Q, and painted the roof myself using a well known brand of exterior metal paint (no not Hammerite), I did it outdoors, got the odd fly stuck, but they do break off at the ankles when paint is dry...and did it as scientifically as reading the instructions on the tin...total cost was £300..this was done in May, it still looks excellent...although I am blowing my own trumpet, it has now lasted far longer than both the pro jobs it has previously had...

Well done. However - your suuccess is down to your appropriate preparation - that`s all thatwas needed in the first place.We ( John and I ) would only use white spirit on bare metal - no solvents whatsoever once we had started the paint process.

 

Someone somewhere among all this suggests that Craftmaster are "on the defensive" here - although I may have misinterepreted the comment. Let me say anyway that Craftmaster has no need to be defensive on any issue involving product quality - especially in the canal market where working conditions are usually inadequate ( even indoors )," professional" skills can be disappointing a lot of the time and where professionals and amateurs alike are unwilling to blame themselves for being less competent than they may have thought.I`ve said it many times - none of the leading brands, absolutely none of them, readily available on the canals, make bad paint. None of us is that bloody stupid.If a well applied paintjob goes wrong it`s extremely unlikely to be a paint fault. Almost zero likelyhood in fact.