Acrylic paint update
Jason James
it scratched with a hose-brush and then 12 months later went all crow's
footed, has upon inspection to remove, gone brittle. The crow'sfoot cracks
go down thru the undercoat, which is light blue?!
So what happened here? The undercoat and the top coat was not sufficiently
dry because they used the wrong thinners as John suggested? The paint also
had a frosted appearance to it.
BTW, some blisters formed which when wire-brushed, went right down to the
metal AND rusted badly with little holes and one big blister, a BIG rust
hole about 2 cms across,..what a mess.
Going to use paint-stripper and get to work repairing the bonnet with
bog,..its an LTD bonnet, so not many around.....
Jason
Ron
news:44872101$1...@news.comindico.com.au:
> The AL paint job which was so soft more than 3 months after the
> respray that it scratched with a hose-brush and then 12 months later
> went all crow's footed, has upon inspection to remove, gone brittle.
> The crow'sfoot cracks go down thru the undercoat, which is light
> blue?!
>
> So what happened here? The undercoat and the top coat was not
> sufficiently dry because they used the wrong thinners as John
Quite possibly. Best to buy it in the 20litre drum from a paint
supplier.
> suggested? The paint also had a frosted appearance to it.
Frosting is often a sign that the air was not warm enough when you
painted it. 25 degrees C is usually the minimum that I have found.
>
> BTW, some blisters formed which when wire-brushed, went right down to
> the metal AND rusted badly with little holes and one big blister, a
> BIG rust hole about 2 cms across,..what a mess.
blisters come from moisture under the paint.
I usually leave the bogged bits in the sun to completely dry, never put
water on it as bog absorbs it beautifully. Spray the undercoat on and
leave for at least 12 hours to dry, never pit water on it as it also
absorbs water. Paint the top coat, leave it for a few days then wet rub
with mild soapy water.
Make sure it is completely dry and add the top coat.
This time of the year is a bad time to paint unless you have a heated
area to do it.
>
> Going to use paint-stripper and get to work repairing the bonnet with
> bog,..its an LTD bonnet, so not many around.....
I don't use paint stripper, have had bad experience of it seeping out of
cracks and making a hell of a mess on the new paint. sanding discs are
the go :-)
Ron
>
> Jason
>
>
>
Jason James
"Ron" <X1...@newsguy.com> wrote in message
news:Xns97DC452AF2E18...@129.250.170.81...
Thanx for the comments, Ron. Which sanding discs are best? I notice there
are those new thick discs which look like a Cruskit biscuit. There's light
grey or nearly white silica ones, and wet & dry.
I found even an expensive tufted wirewheel (about $16 to buy) which produces
sparks on steel, only strips paint for a few minutes then bends over and
burns the paint.
Jason
John_H
>The AL paint job which was so soft more than 3 months after the respray that
>it scratched with a hose-brush and then 12 months later went all crow's
>footed, has upon inspection to remove, gone brittle. The crow'sfoot cracks
>go down thru the undercoat, which is light blue?!
>
>So what happened here? The undercoat and the top coat was not sufficiently
>dry because they used the wrong thinners as John suggested? The paint also
>had a frosted appearance to it.
It's called gunwash. I get mine in 60 litre drums, from an industrial
chemical supplier, for about 20% of the cost of top grade thinners.
Anyone's guess what the constituents are... and they vary considerably
from batch to batch (judging by the smell).
Very cheap and effective way of cleaning spray gear, but I did once
see it being used as primer thinners. I'd imagine the final result
could be very similar to what you describe. :)
--
John H
atec77
shop ? , the belt sander tends to be less damaging in many respects as
personally removing the swirl from wheels is a pain . ( I also have a
small helmanite blaster)
Ron
Jason,
I usually use a tough browm colouerd disc that is good for grinding rust
off metal :-) It lasts a long time and will dig into the metal, so you
have to be carefull. I also forgot to mention you need to spray etch
primer on the metal, before the undercoat. Another thing I do is then
spray "spray putty" on top of that, rub it back, followed by undercoat.
Some times you may need a few goes, before all the "Swirls" are removed.
If you paint the bonnet in a garage of shed with electric wall heaters
or something similar, you should be okay :-)
Ron
Brenden Will
topcoat will not take. It'll lift like your has. Preparation is where 90% of
the paintjob is. I sand undercoat will no smoother than 600grit paper. 800
or 1200 is a no no.
As for acylic being soft. Acrylic will always mark. Marking in some colors
it is very obvious marking. My guess is the color you used is not a good
color in acrylic. Another way to stop marking is after the paint is dry.
Make sure all the protectants are used. Wax, polish blah blah. Any decent
paint shop will put you on the right track. It cost a mate of mine around
$200 from memory for the protectants.
This is my mates car that we painted.
http://i15.photobucket.com/albums/a397/xbwgn/afdwodonga4.jpg Preparation on
that car took 8 weeks as he wanted it perfect. I wasn't so fussed about my
own. I'm not a perfectionist.
Brenden
"Jason James" <ho...@work.1.0> wrote in message
news:44872101$1...@news.comindico.com.au...
Brenden Will
http://i15.photobucket.com/albums/a397/xbwgn/xmascruise5.jpg
"Brenden Will" <br...@hotmail.com> wrote in message
news:128epch...@corp.supernews.com...
Noddy
"Jason James" <ho...@work.1.0> wrote in message
news:44872101$1...@news.comindico.com.au...
> So what happened here? The undercoat and the top coat was not sufficiently
> dry because they used the wrong thinners as John suggested? The paint also
> had a frosted appearance to it.
I'd guess they used gunwash as John suggested, and probably didn't allow
enough drying time between undercoat/topcoat applications.
> BTW, some blisters formed which when wire-brushed, went right down to the
> metal AND rusted badly with little holes and one big blister, a BIG rust
> hole about 2 cms across,..what a mess.
Nice.
> Going to use paint-stripper and get to work repairing the bonnet with
> bog,..its an LTD bonnet, so not many around.....
Here's a good tip to help with bare metal preparation:
Go along to your local chemical supplier and grab a litre of Phosphoric
acid. Mix it in a clean plastic container at a rate of ten parts water to
one part acid, and apply it directly to bare metal areas with a scotchbrite
pad or steel wool (stainless steel wool works better, but scotchbrite works
best I've found).
This mix will kill any rust, and place a nice protective layer over the
metal to prevent any rust forming for a very long time. I've used this stuff
for years, and once applied you can leave a bare metal panel in the elements
for ages before it even looks like rusting (not that you'd want to, but it
is very effective).
Incidentally, this mixture is what Dulux used to sell as a metal conditioner
under the trade name "Deoxidine", except that buying it from a chemical
supplier is around a tenth of the price, and you can "up the dosage" to suit
yourself.
--
Regards,
Noddy.
Jason James
I've seen those. I'll give it a try.
I also forgot to mention you need to spray etch
> primer on the metal, before the undercoat. Another thing I do is then
> spray "spray putty" on top of that, rub it back, followed by undercoat.
> Some times you may need a few goes, before all the "Swirls" are removed.
Yep, I plan to use spray-putty which also claims to be an undercoat as well.
> If you paint the bonnet in a garage of shed with electric wall heaters
> or something similar, you should be okay :-)
Good idea. I remeber a guy who sprayed his Torana in an aircraft hanger.
Then while the enamel was wet a chopper landed, then taxied nearby to
fuel-up blowing gravel particles and dirt onto the car.
Jason
Jason James
"John_H" <john...@hotmail.com> wrote in message
news:0jhe82prfbfiaggq8...@4ax.com...
General purpose thinners, I avoided. The proper paint thinners was about 1/3
more in cost.
Jason
Jason James
Nice job. How many top-coats did he use? Thanx for the paper-grade tip.
Jason
Noddy
"Jason James" <ho...@work.1.0> wrote in message
news:4487...@news.comindico.com.au...
> Yep, I plan to use spray-putty which also claims to be an undercoat as
> well.
One other worthwhile tip for acrylic repairs is to use 2 pak "hi-fill" as
your base system.
One of the biggest problems with acrylic based repairs is shrinkage, and by
using a 2 pak based undercoat/putty you can totally avoid the issue. Acrylic
goes over the top of 2 pak primers just fine, and you'll never get any
problems with shrinkage at all.
--
Regards,
Noddy.
Albm&ctd
> The AL paint job which was so soft more than 3 months after the respray that
> it scratched with a hose-brush and then 12 months later went all crow's
> footed, has upon inspection to remove, gone brittle. The crow'sfoot cracks
> go down thru the undercoat, which is light blue?!
>
'undercoat' over shitty crows foot and it's unlikely you have any stable
surface to apply new primer/surfacer and top coat on to, so you may have
to get it all off if you want a top job. The other approach is to have a
Lada attitude and not really give a toss about what the finish looks
like, in fact drive off at speed if critics attack your paint finish.
It's all the same in the dark at 100 km/h.
Soft acrylic top coat might react well to acetone, allowing you to remove
it rather cheaper than paint stripper. Would cost fuck all to try.
Al
--
I don't take sides.
It's more fun to insult everyone.
http://kwakakid.cjb.net/insult.html
Brenden Will
of mixed paint left. Always leave 1lt for later repairs.
After the paintworks done. Rub back with 1200grit for the experienced and
2000grit for the inexperienced. The paint should feel as smooth as glass.
Then buff with a very mild cutting compound. The wax and polish etc.
"Jason James" <ho...@work.1.0> wrote in message
news:44878657$1...@news.comindico.com.au...
Albm&ctd
Albm&ctd
says...
> 6 base coats and 4 clear. I generally just keep going till I have around 1lt
> of mixed paint left. Always leave 1lt for later repairs.
>
> After the paintworks done. Rub back with 1200grit for the experienced and
> 2000grit for the inexperienced. The paint should feel as smooth as glass.
> Then buff with a very mild cutting compound. The wax and polish etc.
>
Would be a tad quicker IMHO.
Brenden Will
top coat back with 600grit in front of me? I'd be rolling around on the
floor laughing. Why? In a very short few rubs they'll be back to undercoat
and have to respray again. Rubbing back with 600grit is fine if the cars
going to be blown over again.
1200 and 2000grit when rubbed back wet are very very fine. They leave very
slight marks which buff out. Then your left with swirl marks which buff out
again with swirl remover. To give you some idea. To rub back the boot of
that coupe with 1200grit took 4 hours. You'll probably scoff at the time it
took but thats why paintshop charge so much. Quality takes time. There are
short cuts but they aren't for a novice to attempt.
"Albm&ctd" <alb_mand...@connexus.net.au> wrote in message
news:MPG.1ef25766e...@news.readfreenews.net...
Albm&ctd
says...
> 600grit paper leaves deep marks in the paints top coat. If someone rubbed a
> top coat back with 600grit in front of me? I'd be rolling around on the
> floor laughing. Why? In a very short few rubs they'll be back to undercoat
> and have to respray again. Rubbing back with 600grit is fine if the cars
> going to be blown over again.
>
Brenden Will
not to do. I'm still learning tricks though. Off the top of my head I've
sprayed no less than 15 cars.
600grit sand paper is no good on new paint. Maybe very very very old paint.
On new paint you don't want to buff with coarse cut'n'polish. It'll rip
through the paint and possibly burn it. New paint = fine cut'n'polish. Old
paint = as coarse as you can get. I cut'n'polished a mates pile of crap
$1000 VL to make it look nice for a roady last week.
"Albm&ctd" <alb_mand...@connexus.net.au> wrote in message
news:MPG.1ef261763...@news.readfreenews.net...
Jason James
"Noddy" <dg4...@dodo.com.au> wrote in message
news:44878a52$1...@news.comindico.com.au...
Tah for the hint,..I'll check 2-pak undercoat-putty out. I haven't any
experience with 2-pak of anything, but provided its reasonably easy to use,
should be able to handle it.
Acrylic shrinkage is a common problem out here in the sticks cause the
summer temps get so high. Everything was fine (relatively speaking) with the
bonnet and boot (rest of car has very good original paint) until the car
spent one summer out of a garage,..then the AL went pear-shaped.
Jason
Jason James
Sounds good. Remember that popular rust treatment back about 30 yrs? It used
to leave a plasticy red-colured thin layer over rust,probably phosphoric
based as well.
The LTD has no rust apart from the bonnet and around one rear C-pillar and
surface stuff in the boot. The rain out here is bugger-all. If the car was
on the coast it would be a rusting hulk by now I suspect if left untreated.
I have a litre bottle of convertor, but if I find more (shudder) I'll mix up
some of that good stuff you mentioned. The worst blister was directly over a
bonnet brace and the sheet of sound deadener (code for rust hider). Aftr
cleaning and vacuuming the rust and then applying rust treatment and then
bog and refinishing work then painting, I then finish by applying fishoil
spray via the snorkel tube into those inaccessible crevices.
Jason
Noddy
"Jason James" <ho...@work.1.0> wrote in message
> Tah for the hint,..I'll check 2-pak undercoat-putty out. I haven't any
> experience with 2-pak of anything, but provided its reasonably easy to
> use,
> should be able to handle it.
It's no different to normal acrylic primer to use, so you won't have any
problems.
It's somewhat more expensive of course, but there's plenty of cheap
suppliers around for this stuff, and you'll need a good mask.
--
Regards,
Noddy.
Noddy
"Jason James" <ho...@work.1.0> wrote in message
> Sounds good. Remember that popular rust treatment back about 30 yrs? It
> used
> to leave a plasticy red-colured thin layer over rust,probably phosphoric
> based as well.
I think it was, but I never used it much.
There's a number of different metal conditioners on the market. Some good,
some not so. Some make applying paint over the top of them a fucking
horrible task, while others can be pretty aggressive and attack stuff you
don't want touched.
The Phosphoric acid works well because it doesn't hurt anything *other* than
rust, and leaves the bare metal very clean and in a perfect state for paint
bonding.
> The LTD has no rust apart from the bonnet and around one rear C-pillar and
> surface stuff in the boot. The rain out here is bugger-all. If the car was
> on the coast it would be a rusting hulk by now I suspect if left
> untreated.
>
> I have a litre bottle of convertor, but if I find more (shudder) I'll mix
> up
> some of that good stuff you mentioned. The worst blister was directly over
> a
> bonnet brace and the sheet of sound deadener (code for rust hider). Aftr
> cleaning and vacuuming the rust and then applying rust treatment and then
> bog and refinishing work then painting, I then finish by applying fishoil
> spray via the snorkel tube into those inaccessible crevices.
That'll work fine.
While we're on the subject of rust removal, here's another tip that works
well for small removable parts (Just call me Martha :)
Grab yourself some Sodium Carbonate (it's commonly sold in supermarkets as
"water softener" for bathing or laundry use in either crystal or powder
form), and throw a couple of handfuls in a 5 gallon bucket of water. Connect
the part to be cleaned to some wire, and suspend it in the bucket. Grab a
sacrificial steel rod of some sort and drop that in the bucket as well
(taking care to ensure that the rod & the part don't touch).
Connect the Negative lead of a 12V battery charger to the part wire, and the
positive lead to the sacrificial annode and switch the charger on. Within a
few seconds the part will start to "bubble" as the rust is being attacked,
and the length of time required to totally remove the rust will depend
largely on your charger, the degree of rust and how concentrated your
mixture is.
It's a non destructive process that works very well indeed, and I've used it
on a shitload of small items for the coupe I'm surrently doing, such as door
hinges and the like.
You can read more about it here: http://www.bhi.co.uk/hints/rust.htm
--
Regards,
Noddy.
Albm&ctd
> top coat back with 600grit in front of me? I'd be rolling around on the
> floor laughing. Why? In a very short few rubs they'll be back to undercoat
> and have to respray again. Rubbing back with 600grit is fine if the cars
> going to be blown over again.
>
> 1200 and 2000grit when rubbed back wet are very very fine. They leave very
> slight marks which buff out. Then your left with swirl marks which buff out
> again with swirl remover. To give you some idea. To rub back the boot of
> that coupe with 1200grit took 4 hours. You'll probably scoff at the time it
> took but thats why paintshop charge so much. Quality takes time. There are
> short cuts but they aren't for a novice to attempt.
>
thought we were talking about a home handyman type job that is usually
pretty sandy and awful anyway and also thought you were talking about
lightly knocking the fuzz off before buffing.
For the average paint job on an old dung heap done in a home workshop we
seem to be going to a lot of trouble getting that mirror finish which
tends to attract the 20 cent brigade and critics such as those that just
painted a fence with old lumpy paint strained through a stocking.
I'm also wondering where all the tradesmen went that got very acceptable
buffable top coats straight off the gun. Maybe they all died from cancer?
IIRC Jason lives in Qld.. and the summer tends not to be kind to clear or
metallics. Dunno about you but if I had an old Ford dung heap fitting the
horrid mental image of Jasons, I'd do it in a light nonmetallic colour
without clear top coats, making it easy to touch up when the rust pops
through.
I don't do much painting these days but the last I did was for a friend
with a BMW motorcycle and although he complained bitterly when I
requested he remove all the previous clear coat and unstable metallic
paint, then requested he rub back the primer surfacer leaving no
imperfections, rejecting it a couple of times, he was rather impressed
with the final top coats that came up with cutting compound hand applied.
Actually I've got an old fuel tank on a bike painted 13 years ago left in
the weather for the last 10 years, painted with super-cryl series11
but no clear top coat. Although the paint is still quite good apart from
an area that had some filler under it, I'll give a small area a few rubs
with 600 and see if I hit the primer, as you suggest, if not then see if
the scratches will buff out.
It would be quite nice if acrylic were this easy to remove as it would
solve Jasons present problem and have prevented my friend with the BMW
from going 'fark this' and other utterances.
PS:
I'll remember to read posts fully.
I must remember to read posts fully.
I really must remember to read posts fully.
Albm&ctd
atec77
Albm&ctd
01.sydney.pipenetworks.com.au>, atec77##@hotmail.com says...
slight snip
> Albm&ctd wrote:
> > mmm, now to find a bucket big enough for the Lada.
> >
> > Al
> You drive it onto the back yard pool and then raise the sides..
>
I thought it would have to be a bucket for a rust bucket or perhaps a box
for a shit box?
atec77
> In article <4488ea10$0$17549$61c65585@un-2park-reader-
> 01.sydney.pipenetworks.com.au>, atec77##@hotmail.com says...
>
> slight snip
>> Albm&ctd wrote:
>>> mmm, now to find a bucket big enough for the Lada.
>>>
>>> Al
>> You drive it onto the back yard pool and then raise the sides..
>>
> I thought it would have to be a bucket for a rust bucket or perhaps a box
> for a shit box?
>
> Al