So i sanded this piece down with a green brillo pad to ensure proper adhesion.



I then applied two coats of primer. It was looking very good, so I wiped it off with 70% Isopropyl alchohol, dried it, and applied 1 coat of orange. I go out to check it today, and this is waiting for me.



Now this wasn't where I was painting it. I painted this piece along with 3 others in a well ventilated barn that very dark and cooler than the outside. It looks like this is the product of heat, but i'm not sure. The other items I painted in unison with this piece all turned out great. What happened??? I am scrubbing down this item with a brillo pad soaked in paint thinner, and setting it back to square one. I don't understand why this happened....could it have been related to the fact that I was at the bottem of a can on this specific piece? Please help so I can avoid further dissapointments. Thanks

That looks like a few of my previous paintjobs.

In my case it was caused by putting on too much clearcoat but you didn't mention that you used clearcoat.

Its wierd that it only affected 1 piece though...

Quote: Originally Posted by ratchetfps I wiped it off with 70% Isopropyl alchohol...

You could have missed some.

As you said, it looks heat related, because it occured around the edges of the piece. Maybe the metal expanded a lot or something. But that is too weird.

The green pad you speak of, is it like a kitchen scouring pad?

Humidity?....

I'm in So. Cal. and it is humid like a mother right now.

It looks like oil.
Ive had that happen on engine parts that werent completely grease free

I use acetone to degrease on metal.

Maybe some of the alchhal was trapped along the edge and bled into the paint?

Use denatured alcohol from the hardware store. I use it to clean copper on blank circuit boards before masking and etching.

if you use a lacquer paint don't clean it with denatured alcohol since it will strip it off.
it looks like the top layer cured faster than the bottom layers so it wrinkled. what primer are you using? you might want to try a can of duplicolor metal etching primer if your painting aluminum.

The crinkling come from the paint eating the previous layer, possibly from applying too heavy a coats.
The spots in the center(called fisheye) are from oils left on the material.

holy ************************************************

i hope i dont get like this thing im my project !!

Man Good luck to fix it

i think it need sanding befour new paint ( THIS COST )

Good luck

it looks like a humidity/didnt let the primer dry enough,, i have had this happen to me before..it actually looks like paint which i just put on some "spray paint remover" onto..it starts to bubble up..i used it instead of sanding the whole thing down because i found it was MUCH quicker and got to the metal immediatly

Quote: Originally Posted by WuGgaRoO it looks like a humidity/didnt let the primer dry enough,, i have had this happen to me before..it actually looks like paint which i just put on some "spray paint remover" onto..it starts to bubble up..i used it instead of sanding the whole thing down because i found it was MUCH quicker and got to the metal immediatly

Definitely. I did the same thing on my powerbook. The primer only had 1 day to dry, that wasn't enough. My mum's a professional painter, and she told me to wait, but I jumped the gun. What'd you expect? Patience?

it was dead for almost a year.........

Dangit.... I'm really sorry... I followed the link from another thread on this project and completely forgot to check the date. Accept my aplogies?

Quote: Originally Posted by saxartist Dangit.... I'm really sorry... I followed the link from another thread on this project and completely forgot to check the date. Accept my aplogies?

Don't worry about it saxartist. Your response was helpful, and we all make mistakes in forums. Welcome to the site btw!

I would not use alchohol to prep the surface..it just isn't the best for the job..."Prep Sol" wax and grease remover is what we used at the body shop, it comes under other brand names, you can get it from an automotive paint supplier.

Bare metal should have a cleaning with Metal Prep to "Etch" it first idealy to promote paint adhesion...its a mild acid.

Bare metal should also have a somewhat rough texture for the primer to "Bite" on, it looks like the primer lifted under the paint...this is real common if you mix and match paint types, a laquer based paint over an enamel or epoxy primer..its best to use the same primer, top coat and clear coat of the same brand, and definately of the same type (Laquer primer, laquer paint, enamel primer, enamel paint..etc, otherwise it can cause "Lifting" like you had)

The metal should be sanded with 320-400 grit at most, using something like 600-100 grit will be too smooth for the primer to bite into, you can even get away with 120-220 on the primer coat (not recomended though) as long as you sand it before the color coat..wich is always a good idea, primer should be left to dry overnight idealy..but not neccesary...4-5 hours is more than enough if it isn't real thick.


Leave plenty of time between coats (20 mintes) you want reasonably thin layers to build up..not heavy thick coats sprayed quickly. Use some judgement though, when i say a "Coat" I mean enough to cover things, wich could be multiple passes...just don't over do or under do it.

To thin of a coat, and it will have a rough texture, too thick and it won't dry properly (Also called "Flashing") between coats.

Your first few layers, don't worry about it being shiny, your building up a base, they can be somewhat thin.

The last few coats can be a bit thicker, with your final one being heavy enough to make it glossy, without making it run..it should appear "Wet"

If you are using a clearcoat over it, it can be of a slight benefit to put a thin layer of it on while the topcoat is still a bit tacky for good adhesion...one of the "Tricks" we used at the body shop was to mix a small amout of the color in the first coats of clear in our spray guns..it helps it "Blend" but this isn't possible with spray cans.



FYI, as a general note...Laquer thinner will often do the job too, but again, it's not the ideal, but probably better than alcohol since its more compatible at the chemical level...some alchohol will leave behind a residue, unless its the 99% pure stuff.

A revival of an old post, but I experienced the same thing recently, and figured the info might help prevent someone from making a similar oops.

If it is cold where you leave the panel to dry after painting...almost the exact same thing happened when I painted the chassis of the Modding On The Cheap case. The primer (much more forgiving to temperature) went on fine. When that was dry, I sprayed on a few thin coats of metallic black (with about 20 minutes between coats). When I left it, it looked like it was gonna be fine. But several hours later (I did the painting in a heated but rather chilly garage when there was still snow on the ground outside), I came back to see the wrinkle finish you showed. I had to sandblast that sucker to do-over.

wasnt saying its bad, I've never seen this thread and I was wondering how it got so big, then I saw computerking and I knew it was messed up...

I'm sorry if I'm reviving a dead thread and if my question is defeating the purpose, but I wonder if there is a way to reproduce that effect safely?
Safely as in the paint will peel a little on the edges but otherwise stay on? I reckon just covering it with clear-coat won't be enough to sustain it.
It really sucks if a paint job is ruined by this but I could imagine a sweet two colours effect with a darker layer of paint breaking open and revealing some brighter colour.
(Or should I just let it be because sooner or later the paint will peel completely eventually?)

It looks to me like you had two problems. One was 'fish eyes' probably caused by the oils on the tips of your fingers. Use of rubber gloves when handling parts will end this. Also most places that sell automotive paints sell a product known as 'fish eye limiter' that changes the surface tension on the paint applied and eliminates these fish eyes.
I believe the 'krackling' of the top coat is caused by a reaction to the strata of paint beneath. After you wet sand with 320 wet or dry paper you may want to use an automotive sealer to prevent reactions from occuring.
Each paint system is different so thinner recommendation is tough. Take a drop of your top coat paint and put it in a small "shot glass" of thinner. If it slowly disappears then you are OK, but if it curdles you are screwed. Find another thinner. This test works well with paints and clears to make sure you don't have a reaction.
Lastly small light coats, keep your gun parallel, and 50 overlap will keep you from having tiger stripes or dry spots. Good Luck.