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easytime
28-06-14, 08:29 PM
Had a very bad day with the bumper repaint. After getting the gun sorted and laying 2 'perfect coats' this began to creep across the surface until 60% of the bumper was affected. I was meticulous in prepping and am really at a loss to explain this.

Any ideas?

http://gallery.xpowerforums.com/data/500/medium/IMG_0308.JPG
http://gallery.xpowerforums.com/data/500/medium/IMG_0311.JPG

petet16
28-06-14, 08:38 PM
Paint reaction, what did you use to degrease it.

easytime
28-06-14, 08:40 PM
Paint prep wipes then a tack rag, all this after light sanding of a grey acrylic primer.

Lukeus101
28-06-14, 08:40 PM
Had a very bad day with the bumper repaint. After getting the gun sorted and laying 2 'perfect coats' this began to creep across the surface until 60% of the bumper was affected. I was meticulous in prepping and am really at a loss to explain this.

Any ideas?

http://gallery.xpowerforums.com/data/500/medium/IMG_0308.JPG
http://gallery.xpowerforums.com/data/500/medium/IMG_0311.JPG

Too much thinner in the gun?

mrmick
28-06-14, 08:42 PM
Either silicon or polish that's caused that crazing did u panel wipe it and tack rag it before u primered it

petet16
28-06-14, 08:43 PM
I've had that happen if any silicone is left on the panel, you can get a similar effect if the humidity is high as well

easytime
28-06-14, 08:45 PM
Either silicon or polish that's caused that crazing did u panel wipe it and tack rag it before u primered it

Not a trace!!!

2 coats of grey acrylic primer, each sanded lightly, washed off wet and dry sludge with water, dried (garage was warm) paint prep wipes, tack cloth then the blue.

mrmick
28-06-14, 08:46 PM
Its all in the prep

easytime
28-06-14, 08:47 PM
Paint is cellulose blue, cut 50% with acrylic thinners. Primer is acrylic from a rattle can.

easytime
28-06-14, 08:48 PM
Its all in the prep

It has been a week in prep, each step done with care and attention. I was looking out for contamination's at every step, that's why I am so stunned at this reaction.

petet16
28-06-14, 08:50 PM
I would maybe try a test piece prime with the acrylic, then lay some colour coat down, you may be getting a reaction from 2 different types of paint.

mrmick
28-06-14, 08:50 PM
I do a lot of painting and that looks like silicon or polish or if bumper has been painted before with either a sintetic paint and caused a reaction

easytime
28-06-14, 08:51 PM
Sorry blue is cut with 2k thinner as stated by manufacturer. I have done other plastic trims recently with the same paint and mix that turned out perfect, so the 'ingredients' are good.

easytime
28-06-14, 08:51 PM
I do a lot of painting and that looks like silicon or polish or if bumper has been painted before with either a sintetic paint and caused a reaction

What is sintetic?

mrmick
28-06-14, 08:52 PM
You may need to prime it with barrs coat primer it stops all the problems

easytime
28-06-14, 08:54 PM
Primer was done yesterday, sanded today about 3 hours before blue paint went on, there was actually a thin coat of blue below this that was touch dry when 2nd coat went on.

mrmick
28-06-14, 08:56 PM
Its a cheap and nasty paint that a lot of garages use to paint whole panels cause of price

easytime
28-06-14, 08:57 PM
strange that the first 'dusting of blue did not wrinkle like this, could it have been the 1st blue coat doing this?

mrmick
28-06-14, 08:57 PM
Where about are you bud

easytime
28-06-14, 08:57 PM
Its a cheap and nasty paint that a lot of garages use to paint whole panels cause of price

http://www.express-paints.co.uk/mixed-basecoat-colour/

This is the paint.

mrmick
28-06-14, 09:05 PM
Did you wash the gun out with thinners or gun was and before you put paint in gun did you put a bit of 2k thinners through it first

easytime
28-06-14, 09:11 PM
Did you wash the gun out with thinners or gun was and before you put paint in gun did you put a bit of 2k thinners through it first

The gun was washed out after use last time, about a week ago. Then to get the setup on it I put some cellulose thinners into it and a drop 10ml or so of blue, sprayed all of that onto some paper sheets on the wall to get flow and pattern shape correct. Expended all of that onto the wall, say 100ml. Mixed the blue in a new mixing tub with equal part 2k thinner, strained it into the gun (HVLP type) and painted.

mrmick
28-06-14, 09:16 PM
Can only put it down to polish or silicon really had it happen to me a few times all you can do is take it right back and start again really I know its a ball ache

easytime
28-06-14, 09:23 PM
All I can think of is the cloths I was using for the water wipe down after sanding the primer. They were a 10 pack of micro fiber cloths from asda, they might have had 'something' on them that left traces on the bumper. The only paint I used that was different from the previous trims I have done was the primer, it was previously Halfords plastic primer, mo issues with that. This time I used Halfords standard grey primer, it says it is acrylic, but that is the only difference from last time. I am really bummed about this because I have been trying for weeks to get the gun setup right and today it was 100%, beautiful even coat, no runs, no thin patches I was very happy. But as seen after about 2 mins the wrinkles started and 20 mins later most of the bumper was covered.

mrmick
28-06-14, 09:31 PM
Full strip back and start again . I use halfords plastic primer with no problems at all

Mark S
28-06-14, 09:37 PM
Paint is cellulose blue, cut 50% with acrylic thinners. Primer is acrylic from a rattle can.

celly, over rattle can acrylic???

and therein lies your problems!!!

easytime
28-06-14, 09:40 PM
celly, over rattle can acrylic???

and therein lies your problems!!!

They incompatible together?

Bobdope2002
29-06-14, 02:32 AM
eeeeep



Did you use any plastic primer on the bumper prior to grey priming it has to be done unfortunatley

easytime
29-06-14, 11:01 AM
eeeeep



Did you use any plastic primer on the bumper prior to grey priming it has to be done unfortunatley

No, this was on top of a previous paint job. What the primer is on top of is 2p2k clear.

Bobdope2002
29-06-14, 11:05 AM
thats where ya problem lies my friend

in my experience of painting/recoating plastic things they have to be taken back to pretty much naff all then re plastic primered or failing that a good coat of etch primer

two different types of paint brand will clearly differ and the chemicals used in both may not like each other resulting in blistering and a reaction

easytime
29-06-14, 12:16 PM
thats where ya problem lies my friend

in my experience of painting/recoating plastic things they have to be taken back to pretty much naff all then re plastic primered or failing that a good coat of etch primer

two different types of paint brand will clearly differ and the chemicals used in both may not like each other resulting in blistering and a reaction

Etch primer's for metal?

Bobdope2002
29-06-14, 12:19 PM
yep sorry just woke up still drunk

everything i said minus the etch primer bit

its happened to me when i used paint the bits on JCBS, if say a colleague had mixed the ratio say 2:1 and i say did it 3:1 and used a different chemical/harderner then the exact same thing would happen

I have a incling maybe this has happened here

easytime
29-06-14, 12:30 PM
yep sorry just woke up still drunk

everything i said minus the etch primer bit

its happened to me when i used paint the bits on JCBS, if say a colleague had mixed the ratio say 2:1 and i say did it 3:1 and used a different chemical/harderner then the exact same thing would happen

I have a incling maybe this has happened here

The primer was on top of 2p2k clear which is pretty much inert to other chemicals. The primer did not react so it is safe to say that part went ok. The base coat did react that was on top of the primer so the celly had a reaction to the acrylic primer. I have found out that acrylic is not to be used below cellulose for this reason. I did have the bumper back to plastic for the first attempt, the bumper was trophy yellow, but I'm not doing that again as the bumper when stripped was in poor shape with regards to chips and scores. With the first attempt paint still on the bumper is perfectly flat now and an ideal start point. Also it is getting harder to get good paint stripper thanks to the EU.

easytime
29-06-14, 12:59 PM
The first stripper I got from a local motor factors was epic but the last tin he had, it was blistering the paint on contact! That ran out and I got some from home base, alcohol based it done f all really, I don't know why it is called paint remover. Then I got some from a decorating supplies place, that stuff was based on the first stuff I had but apparently it is watered down now due to EU regs. It worked like the first epic stuff but in slow motion, took 3 hours to blister the paint but did remove the paint given the time.
Thanks EU for making a 2 hour job a 3 day effort.

Mark S
29-06-14, 08:03 PM
you seem to have a spray gun and basic eqpt. Why don't you do it properly and buy some 2k primer, top fill will be fine, use a poly base coat and 2k laquar, forget rattle cans, there for the morons of society.

easytime
29-06-14, 08:08 PM
you seem to have a spray gun and basic eqpt. Why don't you do it properly and buy some 2k primer, top fill will be fine, use a poly base coat and 2k laquar, forget rattle cans, there for the morons of society.

only used rattle cans for the plastic primer, the base was celly and top will be 2p2k clear.

Got results today though, some images of before and today.

http://gallery.xpowerforums.com/data/500/medium/IMG_0252.JPG

http://gallery.xpowerforums.com/data/500/medium/IMG_0321.JPG

http://gallery.xpowerforums.com/data/500/medium/IMG_03231.JPG


I am pleased with that.

Mark S
29-06-14, 10:17 PM
if you use 2k products, you will get an out the gun finish and shine, celly will need buffing - thats hard work!!!

easytime
29-06-14, 11:07 PM
if you use 2k products, you will get an out the gun finish and shine, celly will need buffing - thats hard work!!!

I am using a 2p2k clear coat, the base here is trophy blue pearl so it cant be buffed before clear, that satin finish is how it goes on.

petet16
30-06-14, 04:28 AM
It looks fine, once it's clear coated it should come up perfectly.

petet16
30-06-14, 04:30 AM
you seem to have a spray gun and basic eqpt. Why don't you do it properly and buy some 2k primer, top fill will be fine, use a poly base coat and 2k laquar, forget rattle cans, there for the morons of society.

You're certainly emphatic in your opinions, I feel such a moron now :wacko:

peterzs
30-06-14, 08:30 AM
You havnt seen my efforts with Lacquer, on a wheel I had Silver Sparkled. Pete!!

Dont know if I couldnt see it going on, but what a mess!!!

Still it was only a spare and still looks better than it was.

Take my hat off to the guys that get such good finishes, with whatever.

:yikes::yikes: :thumbsup::thumbsup::thumbsup: