Bob da builder
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| posted on 7/1/03 at 11:07 AM |
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Pealing paint!! HELP!!
Are ythere any paint experts out there!????
i have preped and degreased all pannels, etched all alu and firerglass body work with Bodyline 2K etch and top coated with ICI 383 paint as
recommedned by my uncle who is a coach painrter with 45 yr experiance, also recomended by supplier as well.... any way the paint is pealing of the
alu, can rub it off with my finger!!
The etch has stuct like it should but where it has contacted the top coat it has reacted causing a lach of adhesion!!
no one has seen this before, this is the 3rd car that i have painted, previous 2 with no problems.... any idesa why the paint is peeling???
Cheers, Bob.
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heyzee
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| posted on 7/1/03 at 08:51 PM |
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paintwork
i also am a coachbuilder not with 45 years under my belt though.the top coat you have used, ici 383 is a polyurathane top coat,which is a comercial
vehicle type paint.which shines like a sh*t house door when it is put on then generaly fades,due to the fact of chemicals in car and truck washes
etc.it has probably reacted with the etch primer the primer may not have been dry properly,or the top coat thinners might have bittern into the etch
causing it to swell up as if it has had paint stripper put on it.what i would try to do is stripp off all the top coat sand down the etch and start
again.coat it up with etch let it dry (overnight)then lightly scuff it off with 600 or 800 wet and dry.for a top coat i would use two pack paint
although a little more expensive the results are a lot better.and if things do go tits up it is a lot easier to put right.you are also supposed to use
the same brand primer as the topcoat .i.e. i.c.i. incase anything go,s wrong ,so you stand a chance when you tell the supplier his paint is crap
and he sometimes supplies you with a bit more f.o.c.you should be able to purchase a cheap two pack for the price of ici 383 because its not
cheap,unless your uncle had it away from work that is
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stephen_gusterson
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| posted on 7/1/03 at 11:04 PM |
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I did a fantastic job of spraying a metro turbo once.
Did all the undercoats with primer surfacer in a can. Acrylic based.
Put the top coats on with cellulose.
Big mistake.
If the paint was slightly impacted, it didnt scratch - it just chipped lumps off.
The primer wasnt compatible with the top coat.
Use compatable systems or all your work will be for nothing.
My car wasnt exactly losing paint as you watched, but it worried me and inspired me to sell it for 500 quid - good for the time 6 or so years back.
atb
steve
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stephen_gusterson
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| posted on 7/1/03 at 11:06 PM |
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also
about 2 pack.
I have always heard that its lethal to use at home without the proper breathing gear.
Is it as bad as is said?
I didnt use it cos I would like to live to see the results and cyanide fumes in my garage might not have allowed that.
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David Jenkins
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| posted on 8/1/03 at 08:47 AM |
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Steve,
What I was told (and it may be a 2-pack of lies  ) was that any droplets of cellulose paint that get into your lungs will eventually get broken down
and disposed of.
With 2-pack paints they're in there forever - eventually resulting in a silicosis-type affliction. Mind you - 'iso-cyanate' doesn't sound too
pleasant either!
I have some iso-cyanate chromate primer at home, which I only brush on. this is the green-yellow stuff you see sprayed on aircraft in the factories.
While using it I wear a mask with filters designed for paint vapour, and disposable gloves, and I use it either outdoors, or in the doorway of the
garage (it stinks).
Bl**dy good primer, though!
David
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stephen_gusterson
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| posted on 8/1/03 at 11:04 PM |
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Looks like, as I thought, best avoided. I was under the impression that the cyanide element was more instant - ie - stops you breathing.
My father has only 30 - 40% lung efficency caused by smoking. It almost kills him getting up stairs. Its worth looking after your lungs.
atb
steve
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johnston
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| posted on 8/1/03 at 11:40 PM |
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i thought that proper 2 pack was already banned form amatuer use
and the stuff u get now is the same to paint as lrp is to petrol
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David Jenkins
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| posted on 9/1/03 at 09:30 AM |
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quote:
Originally posted by johnston
i thought that proper 2 pack was already banned form amatuer use
So did I - but then I went into a paint shop in London, where it was sitting on the shelf!
I'm sure that place was breaking the law - but I wasn't going to tell them...
another hazard with this stuff is that the correct solvent is MEK (methyl-ethyl-ketone)... described by a 'friend who knows' as 'not inflammable -
explosive is a better description!'. Highly volatile, carcinogenic, and so inflamable that it is near-enough an explosion. Not stuff to keep round
the house...
cheers,
David
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Bob da builder
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| posted on 9/1/03 at 02:21 PM |
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MEK is also bloody good at glueing or should i say melting plactic togrther!! well thats if its the same stuff as in my garage!!
Correct me if im wrong but you cant brush apply 2pack?? im brush painting the top coat none of this spraying stuff!!
still duno wot to do with me peeling paint!!! if i leave it it may go away!!! 
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Mark Allanson
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| posted on 9/1/03 at 06:42 PM |
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the effects of 2k paint if used without an air fed mask are cumulative, you dont die the first time you use it and probably not the second, but
somewhere along the line you will start spraying and never see the results. THE STUFF IS LETHAL UNLESS YOU STAY TO THE SAFETY GUIDELINES.
You should also paint in a temp controlled booth, the hardeners are not designed to make the paint go off by themselves, but need the heat of the
paint oven to fully cure.
If you want good results, buy the paint as a system, etch, primer, isloators, hardeners, solvents and colour coats all from the same paint maker. You
supplier is legally obliged to supply HSAW data on the paint, and also data sheets on how to use it properly, including viscosity requirements etc.
Even using the wrong degreasant between coats can destroy the paint adhesion, because the primers are designed to 'grab' the first liquid they come
into contact with. I once ruined a BMW respray by wet flatting a new 2K high build primer, it was designed to be dry flatted but smart arse here
didn't read the data sheet.
The best systems are 'wet on wet' which is what it says, you just pile on the coats of primer then colour coats and clears one over the other, just
observing a critical recoat time between coats, then baking the whole thing for about 30 mins
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Skirrow
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| posted on 9/1/03 at 08:45 PM |
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Yeah, 2-pack is nasty stuff. Its not got cyanide in it but the cyanate bit is in the same group of chemicals and it is a respiritory poison. You need
a mask with an air feed from outside your booth, and therefore need a booth.
Some people play it down and say it isn't that bad but I wouldn't take the risk. 2-pack is wonderful stuff compared to the rest, more shiny, harder
wearing, less coats needed etc. but if you are spraying in your garage and dont mind spending a bit longer spraying and polishing you should get
almost as good results from cellulose and you shouldn't die in the process.
Besides, I imagine most locost builders spend as much time polishing their pride and joy as they do driving it. Using 2pack means you miss out on
hours of polishing fun. 
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kingr
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| posted on 10/1/03 at 10:11 AM |
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Forgive my stupidity, but if you have to bake 2k paint, can you use it on Fibreglass? I understood fibreglass shrunk if baked, or do you just bake it
at a lower temperature for longer (gas mark 2 for 30 mins rather than gas mark 3 for 10 mins).
Kingr
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Mark Allanson
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| posted on 10/1/03 at 08:11 PM |
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The shrinkage is not in the overall size of the moulding, otherwise the Scimitar I keep repairing would be the size of a pedal car by now!
Shrinkage is when the surface imperfections are amplified by the baking process, or more accurately the cooling down afterwards. Every tiny scratch
comes out the size of the grand canyon. The other problem is any tiny air bubbles in the gel coat tend to pop and ruin the surface.
We painted the first Avion prototype for Richard Oakes who lives and works quite close to us. The preparation that went into that was ridiculous, but
it paid off if anyone has seen this car at the shows (the yellow one)
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Skirrow
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| posted on 10/1/03 at 10:11 PM |
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They dont bake it at a high enough temp to damage the fibreglass, although it might melt rubber trim and stuff.
2-pack works like 2 part adhesive (like epoxy resin in 2 tubes) When tou mix them together a chemical reaction starts which cures the paint. If you
remember school science lessons though you'll remember that heat speeds up chemical reactions so when you bake it, it cures faster.
The problem with doing this stuff in your garage is you cant bake it so it will take ages to dry and because you are in your garage and not a booth,
you will get all kinds of bits of crap, dust and airbourne insects and so on landing on the paintduring the long drying time. Cellulose drys quicker
at normal temps so you dont have sat there wet while it collects whats it the atmosphere for as long.
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Mark Allanson
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| posted on 10/1/03 at 10:24 PM |
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Remember, we bake complete cars, the only thing it melts are the mars bars and boiled sweets left in the glove box
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stephen_gusterson
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| posted on 10/1/03 at 11:12 PM |
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as a point about 2k paint being possibly banned for amatuer use.....
how is a paint factor gonna know you are an amateur? Some kinda licensing system? Or do you just knock up a fake letterhead on your printer, put on
your paint covered overalls, and go and get some pretending to be a pro.
Then, once you have done this, who's gonna find out.
I dont plan on using 2 pack - just wonder how the regulations could ever be enforced for a home sprayer.
atb
Steve
[Edited on 10/1/03 by stephen_gusterson]
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Skirrow
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| posted on 11/1/03 at 12:38 AM |
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quote:
Originally posted by stephen_gusterson
as a point about 2k paint being possibly banned for amatuer use.....
how is a paint factor gonna know you are an amateur? Some kinda licensing system? Or do you just knock up a fake letterhead on your printer, put on
your paint covered overalls, and go and get some pretending to be a pro.
[Edited on 10/1/03 by stephen_gusterson]
I'm not even sure if it is banned at all but if it is is not enforced very well. You dont even need a letterhead, I imagine most places would sell it
to you if you sounded as though you knew what you were talking about or even just said that you work for a re-finisher. Failing that there are plenty
of places on the internet that will sell it. All you need is your credit card details and a mailing address.
I would think that anyone who knows enough to be able to use 2-pack properly and where to buy it from and what to ask for would know enough about the
health risks to not use it at home. Having said that theres always someone foolish enough to ignore saftey issues.
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David Jenkins
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| posted on 11/1/03 at 10:14 PM |
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My local paint supplier for 'real car painters' just won't supply paint to anyone walking in off the street. They want to see an official order
from a registered company.
Of course, if you should make up a company name and print your own 'official order'...
I guess this is down to liability - if they sell paint to an 'amateur' then they could be liable for any harm. If they sell to a 'company' then
that company is responsible for the welfare of its employees.
cheers,
David
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Mark Allanson
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| posted on 12/1/03 at 10:19 PM |
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Every paint wholesaler has to acount for every gram of VOC (volatile organic compounds) that it sells. If it sell to a registered bodyshop, this is
then transfered to the bodyshops VOC acount and it than has to acount for its use or disposal. The bodyshop can reclaim VOC from its acount by
returning used VOC (used thinners or cleaning solvents etc).
The bodyshop wants to keep its VOC use to a minimum because there is a sliding scale of HSE and EPA regulations that they have to adhere to depending
on the amount of VOC used.
If a paint factor sells a litre of paint it has to book it to someone, cellulose can be booked out to private sale, cellulose and synthetic are
getting increasingly hard to get hold of because each factor has to maintain a paint mixing scheme to make the colour that someone orders. This means
they have to keep about 2 litres of every tinter to make any colour that might be ordered, the average scheme has about 50-75 tinters, which they have
to carry about £3000 for every scheme (2K - you can treble that figure) so they aint going to carry a scheme for a paint line that isnt going to sell
enough to justify the maintenance of a mixing scheme.
The time of being able to order a couple of litres of celly to flash over you own car is coming to an end
This means much more business for me!!
Guess where my car is going to be painted!!!! d:
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Skirrow
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| posted on 12/1/03 at 11:33 PM |
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quote:
Originally posted by Mark Allanson
The time of being able to order a couple of litres of celly to flash over you own car is coming to an end
That's bad news, I wasn't aware of that situation. A lot of people, myself included, can't afford to have professional resprays. Especially when
you are a car enthusiast and own more that one that needs respraying.
I hope there will always be a source though, it would suck big time if it became unobtainable. I suppose there is always Halfords aerosols
though....hmm 
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kingr
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| posted on 13/1/03 at 10:19 AM |
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I would imagine that there will be places to get celulose paint for the concievable future, think of it this way : while there may be more shops
selling the paint than there are enough customers to justify tints, innevitably some will drop those tints completely, but there will then be few
shops and more customers, therefore being profitable once again for the shops to have the tints.
The one thing that could cause problems for this is the regulations on mailing of substances. I suspect it probably can be mailed faily easily, but
you may need certifications for the packaging of it. If anything the thinners might be the most dodgy thing as regards mailing, but then, how hard is
it to get celulose thinners?
Kingr
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Skirrow
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| posted on 15/1/03 at 03:01 PM |
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Yeah, I suppose if everyone stopped selling celly, then there would be a nice large gap in the market for me to exploit.
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Mark Allanson
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| posted on 15/1/03 at 06:57 PM |
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It's no loss to locost builders, celly is just about useless on both GRP and aluminium.
synthetic was a much better option as long as you dont want a metallic finish
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Mark Allanson
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| posted on 15/1/03 at 07:40 PM |
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It's no loss to locost builders, celly is just about useless on both GRP and aluminium.
synthetic was a much better option as long as you dont want a metallic finish, it tends to shear (the metallic particles drift in the substrate to
give a hammerite finish)
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Mark Allanson
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| posted on 15/1/03 at 08:47 PM |
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OOps, I seem to have developed a stutter!!
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