Rods 'n' Sods - UK Hot Rod & Street Rod Forums banner

1 - 20 of 38 Posts

·
My name is Martin
Joined
·
2,613 Posts
Discussion Starter · #1 ·
Last night I removed all the snow off the car so today I could take my car out for a drive.

I've noticed that some of the paint is micro blistering. It wasn't there 2 weeks ago, so I guess the cold weather didn't help.

Is there anything that can be done about this, or is it something that's going to bloom up in the winter months?

Car is stored outside all year round with a breathable cover. I've had it 15 months and it was resprayed by the previous owner.
 

·
Cadillac fanatic
Joined
·
890 Posts
Micro blistering normally occurs when cars are covered in sheets, do you have a proper car cover or is it like a cheap tarp type cover, only top dollar car covers will prevent this happening, but even that is NOT gospel.

I would doubt that it was anything to do with the paint now, It was painted a fair while ago, and anything that was going to show would have by now.

Even though the cover is breathable, it is the water content that it holds which causes the micro blistering to occur, water get under the paint and then heats up, causing the paint to lift.
 

·
My name is Martin
Joined
·
2,613 Posts
Discussion Starter · #3 ·
Its a £250 cover, breathable thing. I've had the car since September 08, not sure how long before that it was painted, but like you say it's not recent either way. One wing has always had minor blistering on it, that was pretty hard to notice, but this recent blistering is a patch on the boot and is quite noticeable
 

·
Cadillac fanatic
Joined
·
890 Posts
Its a £250 cover, breathable thing. I've had the car since September 08, not sure how long before that it was painted, but like you say it's not recent either way. One wing has always had minor blistering on it, that was pretty hard to notice, but this recent blistering is a patch on the boot and is quite noticeable
Umm, Not exactly a cheap cover, and no easy cure either, it does sometimes go back down and becomes harder to see, but from experience it never goes away without going right back to the metal, or in the case of Fibreglass, back past the gel coat in some cases.

Bummer
 

·
My name is Martin
Joined
·
2,613 Posts
Discussion Starter · #5 ·
Yep it's an arse.

Question is how many £K do I need to steal to have a full respray done?
 

·
Registered
Joined
·
1,109 Posts
No easy answers on this topic, I've had the same problem on a '73 camaro, I thought it was down to a cheap cover that went on during the worst winter months. A more expensive cover was bought but didn't help... I know this will sound wrong to some but I now think no cover can be a better option.
My Firebird has suffered from micro blistering that has got steadily worse, to the point where it needs totally taking back to bare metal and the start of a mega project. Here's the weird bit- the areas worst hit are those areas exposed most to the sun [roof, tops of wings , hood and trunk] The shadier lower parts of the car are untouched by the blistering.
By the way my 'bird is bright red [ a colour I was advised by a friend not to go for] Won't be red next time!
 

·
Premium Member
Joined
·
4,207 Posts
Micro blistering is moisture trapped in between paint coats,usually at the time of the paint being applied,ie water in airlines,if its in there a car cover will accelerate the apperance of the blisters,if the paint system is moisture free you will never get the problem-ever !,Bry
 

·
www.53catalina.co.uk
Joined
·
2,454 Posts
My car has lots of micro blisters. It's worse on top of the bonnet and boot, but oddly the roof is unaffected. That s a different colour so may have been painted differently.
The vertical sides have much less blistering, but its still there.
The only option is to bare metal the car, but it's a big task, hence I have lived with mone for 5 years now. It hasnt got worse in that time.
I keep the car garaged which may have helped.
 

·
Full Time Metal Junkie
Joined
·
248 Posts
Micro blistering is moisture trapped in between paint coats,usually at the time of the paint being applied,ie water in airlines,if its in there a car cover will accelerate the apperance of the blisters,if the paint system is moisture free you will never get the problem-ever !,Bry
Bingo :D bigjob :tup:
Paint is Porous , so if at the time the layers of paint was applied wet over wet to many times with out proper time between coats or the material was not thinned to proper viscosity this would also trap solvents that will appear much later given the opportunity.
Moisture will travel back down until it hit the steel and return back to the top surfacing any problems on the way...... I have also experienced wet sanding primers with to much talc content which acts like a sponge and traps water.
I have painted in the worst conditions and had show winning results and painted in perfect conditions and dissaster..... I guess what I am saying paint don't care who you are or what your painting you are at its Mersey ... :S
 

·
Registered
Joined
·
1,109 Posts
Sorry if I'm getting obsessive on this one but this subject really bugs me. I get the basic science that moisture trapped in the paint is' breaking out' ,but there almost seems to be no escape from this problem and the amount of money spent on the job almost seems irrelevant .
The 73 Camaro I had painted cheaply [over several previous layers+ various local repairs],it blistered but not terrible...
My Firebird was sanded down to the 'factory' topcoat ,sprayed with a sealer by me, then taken to a well established painter who mostly restores classic cars. So the sprayer is a professional ,using good equipment. When freshly painted it was an excellent 'driver quality' job just what I wanted...but slowly went from small blisters to a total mess!
My last example is a friend's 1st gen Camaro. Taken to bare metal by a top quality painter prep, primed sprayed to a really beautiful show standard. Couple of years later some small bubbles begining to show up:sniff:
 

·
Registered
Joined
·
12,501 Posts
Sorry if I'm getting obsessive on this one but this subject really bugs me. I get the basic science that moisture trapped in the paint is' breaking out' ,but there almost seems to be no escape from this problem and the amount of money spent on the job almost seems irrelevant .
The 73 Camaro I had painted cheaply [over several previous layers+ various local repairs],it blistered but not terrible...
My Firebird was sanded down to the 'factory' topcoat ,sprayed with a sealer by me, then taken to a well established painter who mostly restores classic cars. So the sprayer is a professional ,using good equipment. When freshly painted it was an excellent 'driver quality' job just what I wanted...but slowly went from small blisters to a total mess!
My last example is a friend's 1st gen Camaro. Taken to bare metal by a top quality painter prep, primed sprayed to a really beautiful show standard. Couple of years later some small bubbles begining to show up:sniff:
One has to question the traditional method of wet 'n' dry sanding - if the filler/primer/paint finishes are moisture absorbent then wet sanding and washing down with water or even solvents is likely to cause problems if not given sufficient time to dry out. Perhaps you need to select the time of the year to have the paint job done if you don't want it effected by condensation issues in the painters premises. Would 'drying off' a wet sanded car in a heated booth cause moisture long trapped under the surface to create issues where perhaps if the car was finished under normal atmospheric conditions it would remained dormant (only to raise-up at a later time)?
 

·
Registered
Joined
·
1,109 Posts
You make some good points Roscobbc, I've always used the wet sand method both to keep the dust to a minimum and to stop the paper clogging. The thing is over the years I have done some fairly big repairs on some of my cars [I don't do it as a trade/for a living]and these seem to have lasted better than some of the total resprays done by the pros. Now got to the point where I'd be scared to pay for the really top job , maybe your idea of doing it in the warm dry time of year is the answer!
 

·
Full Time Metal Junkie
Joined
·
248 Posts
Rosco made some great points. I quit painting back around 2002 to concentrate just on the sheet metal part of the job. I remember thinking how much material was costing raising the cost of the overall job, like how much can you charge for these jobs?
The last six to eight years I had installed infra-tech heating to dry the primers and bring the body to an ambient temperature.
This would greatly reduce the opportunity for moisture to be trapped in the primer coats.
The learning curve was what temp to keep the body at while spraying to not flash the base coat to the point of no adhesion.
Once I got the system in order and the timing of the infra-tech versus coatings my jobs had improved the right out of the booth finish. Normally we would (before the infra-tech) let the car in the booth or if weather permitted out in the front yard in the sunlight for a week or two before we would flat sand and buff.
The great part of this new inferred curing was the paint and or top coats would shrink so any small imperfection would be able to flat sand and buff out right away before delivery.
Here is a sample of one of our finished jobs......


Here is one we did for PPG back in 1998 as a pro car for Radiance





Here is our 41 Willys we painted back in 1996 I have a whole build they did an article on. If I can dig it up (before digital cameras ) I will post more.




The Willys is done in a color we made from two tints top coated with blue pearl, stunning changes in lite from purple to blue highlights....
The aqua colored car next to it is a friends 33 Plymouth we painted 6 years before hand and was back for a drop axle up date after a bad accident . I know I have the photo's of the accident I will dig them up and load them for you.
 

·
Registered
Joined
·
12,501 Posts
Very interesting comments - I haven't done any body painting in a long while - at some point my Vette looks as though it will need some sectioning round the o/f front wheel opening and a hood re-paint - may consider doing it myself - in late spring/early summer (after reading some of the above comments)
 

·
Registered
Joined
·
1,109 Posts
Thanks for your input regarding the infra red Steve, I definitely think you have part of the answer here. After all it must heat the inner layers and drive moisture out before new paint is applied , so in theory if the atmosphere is dry and the water filtration on my compressor is OK then micro blistering should be a thing of the past.
Liking your paint, great work!
 

·
I'm a grown up drunk!
Joined
·
2,645 Posts
My Nova was painted by Larry Ward nearly 7 years back,
he painted plenty of other rods and muscle cars in that same oven over several years, also had an in-line air dryer, none of which have any problems worth mentioning except one,
a red 65 el-camino owned by one of our club members, Ian who owned it had no garage space for it as his camaro was in there,
his wife bought him one of those big dollar custom fit outdoor breathable covers,
he always had it covered, never put it on if the truck was wet,
within a couple of years the tops of the wings, bonnet and roof all had plenty of micro blisters, basically all the surfaces where the cover rested on, all the sides were fine,

Larry doesn't cover any of his cars for any long periods of time, me neither,
his opinion is it's best to leave it exposed allowing the paint to breath,

might be a different story covering a car thats garaged as there isn't such a moisture problem.
 

·
Registered
Joined
·
12,501 Posts
Thanks for your input regarding the infra red Steve, I definitely think you have part of the answer here. After all it must heat the inner layers and drive moisture out before new paint is applied , so in theory if the atmosphere is dry and the water filtration on my compressor is OK then micro blistering should be a thing of the past.
Liking your paint, great work!
While we are talking about infra red heating I work for a company that are agents for this type of heating - although our heaters are 1 and 2 KW domestic/light commercial units, not specifically for auto trade use - interestingly there is a IP65 weatherproof unit, suitable for use in all external weathers!
 

·
Premium Member
Joined
·
1,910 Posts
my thames van is in a paint shop at the moment. The old owner kept it coverd and its suffered with micro blistering on the roof bonnet and wing tops.
 

·
Registered
Joined
·
1,109 Posts
My Nova was painted by Larry Ward nearly 7 years back,

Larry doesn't cover any of his cars for any long periods of time, me neither,
his opinion is it's best to leave it exposed allowing the paint to breath,

I hope this is the final answer to our problem ,I know when my car get re-done I will be painting it in summer with infra red and when its finished, NO MORE COVERS !
 

·
Exceeded sell by date
Joined
·
7,742 Posts
A mate of mine had a 70 RT Charger 4spd. in triple black which was restored including a bare metal paint job. The car was an absolute picture and sold to a guy who kept it in a heated garage for a number of years. It then changed hands again and came to live outdoors with me for a short while as a favour. Within a couple of months a chunk of paint came off a rear quarter. I rang the owner and explained that it wasn't caused by my kids it literally just fell off. Within months the whole car was nearly back to bare metal, the paint came off in sheets. Amazing what a change in climate can do even after a number of years.
I think the wet sanding of primers is as much to blame for micro blisters as anything else.
 
1 - 20 of 38 Posts
Top