VOC`s

[Phil Speight]

I`ve started a separate thread from "Paint pimpling" because I don`t want what I say here to be mixed up with anything I said there ! So, no particular response to something already said and no references to any persons or paintjobs previously discussed.

 

Imagine, in the light of commonly held opinion, a steel narrow boat painted in 2014. It has a full synthetic paint system of good dry film thickness. The word nowadays seems to be that it may well micro-blister and that is because of 2010 legislation banning VOC`s. So, each coat was rubbed down when it was properly through dry ( a good painter can tell, as soon as he/she begins rubbing down whether it really is dry ) and as a result of applying the correct number of coats NETT AFTER FLATTING we have somewhere ( hopefully ) between, say,140 and 200 microns of dry paint.

There will be NO VOC`s present in the paint film.

 

Now imagine a second boat, painted in 2008. Apply exactly the same theoretical paintjob as on the 2014 boat - in every detail. Once finished and properly dry we would hope for a similar dry film thickness

and - gosh - there will be no VOC`S present in the paint film. The solid content of the paint, in both cases is what remains to be measured on the boat. Everything that accounted for the difference between the wet and dry film thicknesses has gone. Vanished, in fact, into thin air! That`s why the powers that be deemed the legislation necessary - the VOC`s were considered to become harmful once they evaporated into the atmosphere. They always were absent once the paint had dried. Manufacturers may well have to replace the old solvents now but the end result remains the solid content of the dry paint. Pigments remain the same as does U/V protection and any flow agents.

Driers, present in all synthetics, act chemically to aid the drying process and are not relevant to the VOC debate. Synthetic systems have not suddenly changed into something else.

 

I`ve done this in a very black and white way because that`s how many people see it. There IS reason for concern and much research is being undertaken and acted upon believe it or not, but it could also be said that the 2010 legislation was a bit of a godsend to some when carelessness and bad practice back-fired on them, although that does not apply to the dozens of diligent professionals out there - many of whom I`ve enjoyed working or arguing/debating/discussing various things with for many years. I`ve also not muddied the waters by repeating things I`ve already said about products that were exempted from the legislation. Mainly because most readers, it seems to me, would rather ignore all that.

 

Last thing. As I`ve said before , the paint manufacturer I have been involved with for years is working very hard to solve what is, in the main, a canal problem ( measured by a comparison of blistering complaints across all markets) and they are grateful to the handful of painters who, despite the difficulties they have occasionally faced, have willingly helped.

Edited January 10, 2015 by Phil Speight

[Starcoaster]

What is/are these VOC's that seem to be the cause of so much debate?

Edited January 10, 2015 by Starcoaster

[NB Lola]

Greenie Phil, excellent post

[bizzard]

Very orrible content.

[mark99]

I guess the only way to determine the cause of any micro-blistering, in each case, is to take a sample of the affected area and have it examined and tested in an independent test house/lab.

 

(In my example, I've always suspected the application process with respect to the particular ambients at the time was faulty not the material used. But absence of lab tests means it's a guess).

 

Some questions I've thought as relevant:

 

a) How many paint docks in close proximity to water use a proper wet/dry bulb hygrometer at all stages of the process to determine relative dewpoint and

 

1) log the results for QA?

2) find the dewpoint is non preferable and stop painting?

 

b ) monitor ambient temps and log?

 

c ) Use a film thickness gauge and log results?

 

d) Have the surface preparations checked/signed off/logged by an independent, even if it's only an experienced peer?

 

I genuinely don't know the answers to the above questions as yet I've not commissioned paintworks on a boat myself and hence not looked into how much of this checking is done.

 

 

 

Edited January 11, 2015 by mark99

[Barry]

What is/are these VOC's that seem to be the cause of so much debate?

 

I'm guessing at Volatile Organic Compounds Starry. I googled same and found a description on Wiki that mentions them being in paint (here)

 

 

I think I could be wrong though

[EEng]

I don't know about boats but we do a lot of work (commercial factory) at a place that has a high end spray shop for their products, including a robot spray shop, the spray shop manager has been there for 30+ years and their paint finish is better than a mercedes car and their high end products (all hand sprayed) cost in the region of 5 figures. They have slowly switched from solvent based (VOC) paints to water based paints due to legislation and unlike most have only just started changing recently as they have a special plant that eats the solvents before they go to the atmosphere from the spray shop, the water based paint is not as good according to the manager and never will be, it doesn't wear as well and is harder to spray to get the same finish, in some cases the process takes longer and after time has problems unlike the old solvent based paints bear in mind this is not a boat that is out in the weather but an inside product. The council monitor this companies emissions from their spray shop extract and they have to be under a certain limit, if they go over this they get heavily fined.

 

Some notes here

 

http://www.coatings.org.uk/Coatings_Care/VOC_Product_Regulations.aspx

 

The regulations were bought in 2005 and came into force in 2010 i believe

 

http://www.legislation.gov.uk/uksi/2005/2773/contents/made

 

This is only what i know from the chat over the years at the spray shop where we have worked and i am no expert

 

 

[mark99]

I've cut and pasted this from a car site re pimpling (Paintyourcar.com). It does not single out the materiel but the application (which is my belief as said above).

 

"Blistering
These are the swollen areas on the topcoat film of your paint, which look like bumps, bubbles or pimples. More often than not, you will notice these marks only months after paint has been applied.

Cause:
Blistering is often caused by the confinement of moisture underneath the paint film. This, in turn, is caused by contaminated air lines, inadequate drying time after wet sanding and spraying in places with extremely high humidity.

The use of poor grade reducer or thinner or one that evaporates too fast is also another reason that could cause bumps or bubbles to appear on your car paint. It could also be because of the solvents that have been trapped after the application of wet heavy coatings with insufficient flash time in between coatings. Applying paint over rust, grease or oil and inadequate drying time of undercoats before the application of top-coating are also other reasons for the appearance of this type of blemish.

Repair:
These pimple or bubble blemishes can be repaired through the removal and refinishing of affected areas. In extreme cases though, marked parts should be stripped until you arrive at the bare substrate before you can start with the refinishing process.

Prevention:
If you prefer to do wet sanding, you must allow adequate time for the evaporation of the moisture. You must keep away from wet sanding any lacquer primer surface whenever possible though. Moisture from air lines and your compressor should also be drained frequently. When applying paint during humid conditions, you must add a retarder or allow added flash time in between coatings. If possible, only spray during low humidity weather.

You can also prevent blistering from happening of you will choose the adequate reducer or thinner for spraying conditions. You should also allow undercoating to cure or dry thoroughly before applying the top-coating.

Materials or products should also be applied based on the recommendations posed by the manufacturer and you should also allow the proper flash time before applying another coating. It is also best if you will prep and clean the substrate with the use only of recommended procedures and products".

END of Quote

I know I keep banging on about this but this link below shows a typical example of how external professional steel painting should be undertaken, checked and controlled and how we used to do it for external steelwork. It's quite comprehensive.

http://www.scribd.com/doc/61186675/Painting-Procedure-Template

From that link above here is the window allowable for painting:

"Unless otherwise recommended by the paint manufacturer and accepted by theCustomer, paints shall NOT be applied when:

 

5.2.1Incomplete surface preparation or oil, grease and dust still present onsubstrate to be painted.

 

5.2.2 The surface temperature is less than 3°C above Dew point.

 

5.2.3 The air or surface temperature is below 5°C as it would adversely affectcuring of Paint.

 

5.2.4 The relative humidity of air is greater than 85% except for inorganic zincsilicate up to 90%.

 

5.2.5 The metal substrate temperature is higher than that recommended by thepaint manufacturer for application

 

5.2.6 There is a likelihood of an adverse change in weather conditions withintwo hours after application that would result in a drastic drop in air temperature below those as specified above.

 

5.2.7 There is a deposition of moisture in the form of rain, condensation etc.upon the surface.

 

5.2.8 The available light is less than 500 Lux

 

Blast cleaned or power disc grinded surfaces shall be coated with the primer specified within four (4) hours after blasting or power grinding or within such other limits as may be specified and before any visible rusting occurs. Each coat of paintshall dry for a time period within the limits prescribed by the Paint Manufacturer before the next coat is applied (minimum and maximum over-coating time)"

Edited January 11, 2015 by mark99

[Neil2]

Can we just clear up one thing that is confusing me - AFAIIA there is no "ban" on VOC's in paint, but the levels have had to be reduced since 2010.

 

So I presume there is now a higher concentration of pigment in modern solvent based paint?

 

So can't you just reduce it by adding solvent yourself?

[Sabcat]

I painted our boat in 2014. Inside a floating dock that I hired for a week. I'm not a pro painter, I've never painted a boat before in fact. I set my target relatively low - a boat with no rust, covered in paint that didn't just fall off - and I achieved that using HMG coach enamel. After the first couple of frosts I noticed micro blistering on parts of the boat. The front and the back. The cabin sides are still as they were when the boat came out of the dock - a decent finish I'm pleased with but if someone had paid me £7k to do it they'd have wanted their money back.

 

I got 4 top coats on the boat when it was in the dock. The way I did this was a coat a day cabin sides first, then the front, then the back.

 

The point I'm making is that if the micro blisters were a consequence of the chemicals in the paint then surely all of it would be micro blistered, not just the bits I painted towards the end of the day. The blistering can only be a result of something I did or didn't do. If I had to take a guess it was due to the paint still being wet as the temperature dropped at the end of the day's painting on the front and back of the boat. I can live with it.

[Phil Speight]

 

I'm guessing at Volatile Organic Compounds Starry. I googled same and found a description on Wiki that mentions them being in paint (here)

 

 

I think I could be wrong though

You`re right !

Can we just clear up one thing that is confusing me - AFAIIA there is no "ban" on VOC's in paint, but the levels have had to be reduced since 2010.

 

So I presume there is now a higher concentration of pigment in modern solvent based paint?

 

So can't you just reduce it by adding solvent yourself?

Errr...No. The paint manufacturer has already done that. You should add only an approved brushing additive in modest quantities if the need arises.

You`re right !

Errr...No. The paint manufacturer has already done that with an appropriate and legal solvent(s) containing fewer VOCs. . You should add only an approved brushing additive in modest quantities if the need arises. My op was deliberately presented using the "facts" as people seem to understand them. I know there are still VOCs in many paints.

I guess the only way to determine the cause of any micro-blistering, in each case, is to take a sample of the affected area and have it examined and tested in an independent test house/lab.

 

(In my example, I've always suspected the application process with respect to the particular ambients at the time was faulty not the material used. But absence of lab tests means it's a guess).

 

Some questions I've thought as relevant:

 

a) How many paint docks in close proximity to water use a proper wet/dry bulb hygrometer at all stages of the process to determine relative dewpoint and

 

1) log the results for QA?

2) find the dewpoint is non preferable and stop painting?

 

b ) monitor ambient temps and log?

 

c ) Use a film thickness gauge and log results?

 

d) Have the surface preparations checked/signed off/logged by an independent, even if it's only an experienced peer?

 

I genuinely don't know the answers to the above questions as yet I've not commissioned paintworks on a boat myself and hence not looked into how much of this checking is done.

 

 

 

Relevant - but possibly unpopular in some areas !

[Barry]

You`re right !

 

Hurrah!

 

Do you want an apprentice, Phil, seeing as I am obviously a natural talent?

Edited January 11, 2015 by Bazza2

[madcat]

Interesting.

[Higgs]

Some questions I've thought as relevant:

 

a) How many paint docks in close proximity to water use a proper wet/dry bulb hygrometer at all stages of the process to determine relative dewpoint and

 

1) log the results for QA?

2) find the dewpoint is non preferable and stop painting?

 

b ) monitor ambient temps and log?

 

c ) Use a film thickness gauge and log results?

 

d) Have the surface preparations checked/signed off/logged by an independent, even if it's only an experienced peer?

 

I genuinely don't know the answers to the above questions as yet I've not commissioned paintworks on a boat myself and hence not looked into how much of this checking is done.

 

 

 

 

 

 

Non - It's intuitive. 'Black art'.

 

It's called experience. You probably couldn't think of the questions a painter asks themselves. A carpenter knows wood and has a feeling for the material. Everyone acquires experience in their prospectives lines of work.

[Boat&Bikes]

Non - It's intuitive. 'Black art'.

 

It's called experience. You probably couldn't think of the questions a painter asks themselves. A carpenter knows wood and has a feeling for the material. Everyone acquires experience in their prospectives lines of work.

Then its a pity painters/paint manufacturers cant get their acts together. Imagine if car and motorbike producers sold vehicles that had paint failing just after they sold them, they would go bust pretty quickly.

 

Ian.

[kitman]

Some questions I've thought as relevant:

 

a) How many paint docks in close proximity to water use a proper wet/dry bulb hygrometer at all stages of the process to determine relative dewpoint and

 

1) log the results for QA?

2) find the dewpoint is non preferable and stop painting?

 

b ) monitor ambient temps and log?

I wanted answer because I feel I have something to offer on this.

 

We record atmosphere every six minutes using data loggers when we have a boat in (which is most of the year). The equipment records and stores Relative humidity, air temp and surface temp on a tamper proof computer file. You have to be a bit techie minded to make sense of it all though!

 

Effectively we have a detailed record of the atmosphere of our dock night and day all year round, including all the dewpoints, so we can see at a glance how the dock is performing. Exciting huh?! I can see you all glazing over.

 

In combination with the data loggers, Myself and my staff also use dewpoint meters for spot checks before painting, so we always know when dewpoint temp is 3degrees above steel temp, spot checks get recorded as well but only on an excel spreadsheet.

 

In terms of how many other boatyards or painters do this, well, I'm not convinced data recording is common at all.

 

c ) Use a film thickness gauge and log results?

Again, I monitor thickness as I go to make sure we are creating the specified depth. Results aren't logged at present, but can be checked at any time by measuring the coating.

 

d) Have the surface preparations checked/signed off/logged by an independent, even if it's only an experienced peer?

I feel an independent would be better than an experienced peer. But, no, we don't do this, although I agree it is a good idea. They do it with the paint jobs for the super yachts, but then again we are talking £500,000.00 for a super yacht paint job compared to £8500.00 for a narrowboat paint job.

 

Like I said, I think inspection by a specialist is a good idea, I have spoken about this to International Paints before. They have said that for what it would cost it's not worth doing. And unless boat painting prices rise to accommodate the cost of doing it, it's unlikely to ever happen. The phrase International used was 'horses for courses'. In short, boater's aren't paying enough for this level of service. As if the repaints didn't cost enough already huh?!

 

Moving back to atmosphere monitoring and recording. I see the posts you have made in relation to monitoring conditions effectively on this thread and others. I think you are right to recommend customers check their prospective painter is doing this (doing this correctly I hasten to add!). It's important to record the data because it gives the customers reassurance that the atmosphere is being properly checked and maintained. And if a fault occurs later, which it may do, there are records to point to why.

 

However, further to the above it's fair to say that recording temps daily is still not high on the majority of customer's "suitable painter" check-lists.

 

In fact I read on CWDF the other day that a good professional paint job consists of "taking the windows out", but not much beyond that from what I gather!

[David Schweizer]

I wanted answer because I feel I have something to offer on this.

 

We record atmosphere every six minutes using data loggers when we have a boat in (which is most of the year). The equipment records and stores Relative humidity, air temp and surface temp on a tamper proof computer file. You have to be a bit techie minded to make sense of it all though!

 

Effectively we have a detailed record of the atmosphere of our dock night and day all year round, including all the dewpoints, so we can see at a glance how the dock is performing. Exciting huh?! I can see you all glazing over.

 

In combination with the data loggers, Myself and my staff also use dewpoint meters for spot checks before painting, so we always know when dewpoint temp is 3degrees above steel temp, spot checks get recorded as well but only on an excel spreadsheet.

 

In terms of how many other boatyards or painters do this, well, I'm not convinced data recording is common at all.

 

Again, I monitor thickness as I go to make sure we are creating the specified depth. Results aren't logged at present, but can be checked at any time by measuring the coating.

 

I feel an independent would be better than an experienced peer. But, no, we don't do this, although I agree it is a good idea. They do it with the paint jobs for the super yachts, but then again we are talking £500,000.00 for a super yacht paint job compared to £8500.00 for a narrowboat paint job.

 

Like I said, I think inspection by a specialist is a good idea, I have spoken about this to International Paints before. They have said that for what it would cost it's not worth doing. And unless boat painting prices rise to accommodate the cost of doing it, it's unlikely to ever happen. The phrase International used was 'horses for courses'. In short, boater's aren't paying enough for this level of service. As if the repaints didn't cost enough already huh?!

 

Moving back to atmosphere monitoring and recording. I see the posts you have made in relation to monitoring conditions effectively on this thread and others. I think you are right to recommend customers check their prospective painter is doing this (doing this correctly I hasten to add!). It's important to record the data because it gives the customers reassurance that the atmosphere is being properly checked and maintained. And if a fault occurs later, which it may do, there are records to point to why.

 

However, further to the above it's fair to say that recording temps daily is still not high on the majority of customer's "suitable painter" check-lists.

 

In fact I read on CWDF the other day that a good professional paint job consists of "taking the windows out", but not much beyond that from what I gather!

 

Someone may have posted that, although I cannot recall that statement being made. What does get posted frequently is that a good paint job involves removing the windows and all the fittings, and cleaning back to bare metal,before applying any paint

[Higgs]

I think you are right to recommend customers check their prospective painter is doing this (doing this correctly I hasten to add!).

 

As long as the customer is a professional painter. Nobody likes people standing over them while they work, especially customers that have read a few books on painting and think they could paint better.

Edited January 13, 2015 by Higgs

[Higgs]

 

Someone may have posted that, although I cannot recall that statement being made. What does get posted frequently is that a good paint job involves removing the windows and all the fittings, and cleaning back to bare metal,before applying any paint

 

I used to polish the brass too, but I'm afraid not always.

[mark99]

 

 

Non - It's intuitive. 'Black art'.

 

It's called experience. You probably couldn't think of the questions a painter asks themselves. A carpenter knows wood and has a feeling for the material. Everyone acquires experience in their prospectives lines of work.

 

All the logging mentioned above (and more) was done by us when we had painters paint (not boats) welded steel structural work (outside). At the end of every day, the log sheets were brought to us by the coat and wrap inspector for review, sign off debrief (normally with weld reports too) - all records were compiled for the client handover files.

 

So it's not a universal black art - some industries do it as second nature - some do it by experience I guess and some some-where in between.

 

One job (bridge over Thames***) where the records came in handy was when the paint failed. The paint experts first call "was prove me you applied the paint properly". Once the records were produced the focus went straight to his specified paints which were proved faulty - I'm not sure we would have got anywhere without backed up records. (Then followed a commercial case for losses).

 

We did almost no painting between Oct and April because external ambients made it very hard to get a decent paint window in the working day.

 

I'm glad to hear that at least one paint co seems to do what is probably, best practice QA and is on top of the game.

 

 

*** Of interest was whilst we were working on the Bridge near Putney, (6 months) we had to hang a big bale of straw off the bridge dangling over the river to warn shipping that we were working overhead.

Edited January 13, 2015 by mark99

[Higgs]

 

All the logging mentioned above (and more) was done by us when we had painters paint (not boats) welded steel structural work (outside). At the end of every day, the log sheets were brought to us by the coat and wrap inspector for review, sign off debrief (normally with weld reports too) - all records were compiled for the client handover files.

 

So it's not a universal black art - some industries do it as second nature - some do it by experience I guess and some some-where in between.

 

 

 

I'm glad to hear that at least one paint co seems to do what is probably, best practice QA and is on top of the game.

 

 

 

 

 

The scale and type of work mentioned are very different. I'm sure, in those large scale projects, keeping those types of record was prudent.

 

In the work I'm currently doing, the tools are calibrated frequently, each person signs out their work, piles and piles of paper follow the job, and at the end, these records are archived. It isn't a painting job.

 

I'm a confident painter (was) and have always relied on my work, knowledge and experience to give the customer confidence. A bit like a good chef. I never had an empty book. I was the piece of equipment that was calibrated and making all of the calculations. If all else had failed or lost calibration, I could always depend on me. Never got out of bed then, or now, to do a bad days work. What's more, I enjoyed it. Couldn't figure that out sometimes, because I put hundreds of unpaid hours in, and it was hard graft.

 

I wasn't employed to get it wrong. Some of the biggest firms with all the tech help they can afford make big mistakes. In some cases they rely too much on the tech and still get it wrong. Can't say don't use tech, but it could fail.

[smileypete]

Could be revealing to paint a narrowboat roof with the same topcoat but sections with different primers, flatting, number of coats and see which bits then keep the dreaded microblisters away!

 

In engineering the stiffness of a beam is proportional to the square of it's height, so all else equal, a thicker paint coat should better resist blistering.

 

cheers, Pete.

~smpt~

Edited January 13, 2015 by smileypete