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Basecoat Did Not Adhere

31K views 126 replies 18 participants last post by  69 widetrack 
#1 ·
I have gotten myself into another newbie screw up, but I don't know what I did wrong and could really use some guidance.

This is an 05 superduty. I had some major bodywork on the bed, but the cab was sound. Original paint was sanded flat with 180 (did not break through to metal) and I sprayed 3 coats of SPI 2k. That was sanded flat with 320 and then 600.

4 coats of TCPGlobal's Restoration Shop basecoat was applied (coverage was less than expected) with a half hour between coats. Outside temperature was 66 degrees with a humidity of 40%. I only had slow reducer in stock, so I have it a much longer recoat time to be safe (TS says 10 minutes at 70). The base flashed off in approx 10 minutes. The basecoat was activated with SPI clear coat activator.

I waited 1 hour and shot SPI Intercoat Clear with HOK Ice Pearl. 2 coats, 30 minutes between coats. Intercoat was activated as well. Temperature was 75 degrees at time of shooting intercoat and stayed above 65 degrees for about 6 hours. I do not know actual metal temperature.

Truck sat overnight and 5 coats of SPI Universal was applied with 45 minutes between coats, normal activator with a air temperature of 75 degrees.

The truck was untaped the next day and pulled into the sun. I have waited 1 week in the sun (as I normally do) and started color sanding. I then noticed the basecoat is peeling off of both front doors in sheets. I have attached pictures in this link: Paint Delamination pictures by Brad4321 - Photobucket . I also added one picture of the hood a day after being painted. The paint looked really good, layed down like normal, and I didn't expect this to happen.

In the peeled paint, I can see grey outlines of where I sanded. This is the first vehicle I sanded with 600 before basecoat, I have always stopped at 320. I sanded to 600 as I read on here that it gives a smoother finish to metallics, pearl, flake, and etc. I strongly suspect that this is the source of failure, but I am not certain. The temperature was also marginal, but I have never had problems before with this temp.

It is actively peeling from both doors, but not from the rest of the truck. It may very well peel from the entire truck, I haven't tried past the doors. I should also mention that I used SPI waterborne and tact rags as well.

Anyone know the cause of this and how I should fix? Can I sand it back down to spi primer or will I need to start all over?
 
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#3 ·
I've used activator in my base and I dont think that is your problem. Berry says 1 oz per thinned qt will help your base become stronger. Done it many times. Seeing as how the base is peeling from the primer I would say either you didnt get it clean enough or you didn't get it sanded enough. I always sand my primer with 320 or 400 and thats it. no 600 or finer. Just did a black hood and no sand marks.
 
#4 ·
I wish the whole "2k" description would leave the paint world, I have to assume "2K" means Urethane, but being every product that you put a hardener in including epoxy are a 2K I am not sure what was used here.

But anyway, was the primer sanded wet? How long did you wait after sanding before base coat was sprayed?

The lack of adhesion is between the primer and base is what we are talking about so something to do with how it was sanded and how the base was applied is the issue.

First off, 600 isn't too fine if everything is done properly, heck, you don't even use 600 on a blend panel, 1000 is often used, or even a gray scuff pad. I am thinking either the primer was wet sanded and it wasn't throughly dry that could be an issue. It is unlikely being it's such a big job, unless these panels that are peeling were the last ones sanded right before it was painted. Is it peeling everywhere? Or is it just these panels, and are these the last panels sanded?

Next possibility, were these the last panels sanded and the urethane primer "healed" before it was painted? Some urethane primers can do this more than others. One primer I use has something crazy like a 4 hour window after sanding to paint, it "heals" that fast. So if it was sanded and sat for a number of days this could be the problem.

That and of course the metal temp was too hot and the basecoat flashed the second it was hit and didn't bite the primer.

Brian
 
#7 ·
Next possibility, were these the FIRST panels sanded and the urethane primer "healed" before it was painted? Some urethane primers can do this more than others. One primer I use has something crazy like a 4 hour window after sanding to paint, it "heals" that fast. So if it was sanded and sat for a number of days this could be the problem.
Brian
I'm sorry, I meant to say they were the FIRST panels sanded thus they sat longer before the paint was applied. And yes as Henry stated wet sanding helps the ISO's kick even more and often the urethane primer will have a different recoat time if it is wet sanded than dry sanded. Being sorter if it's wet sanded allowing less time to get the top coat on.

Brian
 
#5 ·
It is human nature and takes practice not to apply more on the horizontal surfaces so the hood is a common place for too much material which can cause problems like you have.

If the doors are the only things peeling, and the hood is the only place that did that, you have to think what was different with THOSE parts primer and paint application? Let's say the whole truck is peeling but the tail gate, yet they were all sanded with 600, you can eliminate that as the reason, if the whole truck was painted at once, but the tail gate was done the next day after you sanded it the morning of, that can tell you that the wait after sanding on the truck is the problem. If the tailgate was sprayed in a different temp, that could be the reason it worked and the rest didn't.

Toss out all your preconceved thoughts blaming something and study it to see WHAT WAS DIFFERENT about the panels that are failing? Why is the hood different than other panels? THESE are the questions you need to ask yourself.

Brian
 
#6 ·
good response. Could also be he wet sanded, didn't clean the sludge off, then tried to rinse it off after it turned to concrete.:D Or it could have been sanded, left to collect dirt in the scratches, then painted. Are we talking Urethane 2k? As Brian mentioned, technically anything with two parts is a 2k but most companies will call a Urethane Primer a 2k, but just want to be sure cause if it's an etch 2k the acids in it might be giving you trouble.
 
#8 ·
As swvalcon said, Barry recommends adding activator to the base and intercoat. I have done this before without issue, so I do not think that is it.

The primer I used is "regular 2k" from SPI. That is what it is named. Yes, it is urethane primer.

I did not wet sand. I always dry sand primer. The primer was shot and sanded the day before. It was approx 12 hours inbetween applying the primer and the base. The last coats of primer were block sanded first with 320 and then 600. I was wondering myself if I missed a spot sanding when I first seen it flake off, but I didn't miss the entire door.

After sanding, I clean with waterborne wax and grease remover and a white, lint free cloth until no more dirt shows up. The towel comes out clean. I give the waterborne about 30 minutes to dry with the booth fans on.

I didn't measure metal temp sadly enough, but I did monitor air temp. If anything, the metal was too cold not too hot.

The hood doesn't have any issues that I am aware of, just the doors currently (I have not tried to peel the paint on the rest of the truck, the doors started peeling on their own while color sanding). I added a picture of the hood basically to show what it looked like before sanding and doesn't have any real relevance to the discussion.

It is quite possible that I sanded the doors first. I don't remember, but it is likely. I waited about 1 hour after applying the primer to sand (SPI says 20 minutes). I wouldn't think that SPI primer has this "healing" property if it says to sand in 20 with no recoat window. Anyone know for sure?

I don't know of anything I did different between panels or for any other vehicle I have done. I thought that the bit of grey and sand scratches on the peeled paint might be a clue to someone in the field as to what went wrong. I am fishing for ideas on the cause so I don't make the same mistake twice.
 
#9 ·
Barry may recommend it, but does the manufacturer of the paint? THAT is who I would listen too about a product. He may very well be right, I am not saying he is wrong, but the manufacturer of the product is who you need to go to for something like that. It's like this peeling problem, now go to Barry, he may have some answers for you.

I am suspecting that the waterborne wax and grease remover may be at play here. It can be VERY slow evaporating, if you used it as liberally as it sounds you did that may be the crux of the problem here in that one of two things. The waterborne could have help to "kick" it healing it OR it soaked up the water and that came up between the base and primer eliminating the adhesion of the base.

With so little adhesion that the paint came off during color sanding!:pain: That is some SERIOUS loss of adhesion, one I have never seen before in my 35 years of doing this stuff.

I am thinking the primer had soaked up some water, it shouldn't as it's a quality 2k but that is what it looks like to me. Maybe the mixing ratio wasn't right on?

Brian
 
#10 ·
Brain I've been doing this for 40 yrs and I've never seen that big of a area peel like that. I dont think the water borne wax and grease would do it unless as you said he didnt get it dry. I've used it but just didnt care for it so went back to the solvent. With that long of a time span before the frist coat of paint I think a quick scuff with a scuff pad should have been done. Just cheap insurance. It's either the primer closed up or a flim between the primer and frist coat of paint and at this point its kind of hard to tell which.All that can be done is strip and redo.
 
#11 ·
You may be very right, or I am right, or we both are and the "Planets were aligned" with a little of both!:mwink: I am thinking it's something like that.

The only thing that comes close to that type of failure that I have ever seen was my sanding the basecoat test, now THAT peeled off in sheets too.

Brian
 
#12 ·
I know it said sanding can happen in 20 minutes but I've never sanded primer within an hour. That right there raises an eyebrow but again, I've never sanded a primer within an hour so don't know for sure if it healed up your scratches or not, but do know those sand times are given with the thought that you are spraying in ideal conditions, which affect curing time.

Interested in hearing what Barry says, the guy is a mad genius with some of his posts. :D
 
#14 ·
I know it said sanding can happen in 20 minutes but I've never sanded primer within an hour.
It wouldn't "heal" (from what I understand) from that as much as it would simply have solvents that didn't fully flash. But if this was left for a day it would certainly have flashed and sanding it open, though a little too soon would have helped it flash. After 12 hours of cure time before base this is pretty much a moot point I think, I think that is. :D

Brian
 
#13 ·
Now that you mention it, this is the first time I have used Barry's waterborne, so that is a new factor in the puzzle too. I have always used solvent base from my local supplier. I like Barry's waterborne much better than the solvent base I was using (I can visibly tell the cleaning difference if nothing else). I turn on the booth fans, wipe the vehicle down until clean and wait 30 minutes with the fans on, tack it off and start spraying. This has been my standard procedure and didn't think twice about it with the waterborne. The truck never sat outside and didn't contact any moisture outside of the waterborne. This gives me two things different from my usual procedure: sanding with 600 and waterborne wax and grease. While it is true I haven't talked to TCP about activating their basecoat, I have used Restoration Shop a few times in the past activated with universal clear activator without issue, so that isn't my first thought.

I would need to scuff the primer for sitting overnight between sanding and base? I have never done that before, but if it is recommended I will start. I didn't realize that urethane primer has self healing properties, so that is really good knowledge.

Yeah, I am really interested in seeing what Barry says too. I posted this here instead of contacting him directly to get everyone's comment and hopefully help out a few other new painters too. I did a search and didn't see anyone discuss this problem before.
 
#15 ·
I would need to scuff the primer for sitting overnight between sanding and base? I have never done that before, but if it is recommended I will start. I didn't realize that urethane primer has self healing properties, so that is really good knowledge.
I DON'T know if this particular urethane has much of a "healing" property. I know that others that I have used have and some are VERY short as I mentioned. I did my Gran Sport in it and after sanding the car, right before it went in the booth yes, it got a scuff over the entire thing with a gray scuff pad just to be sure.

Brian
 
#16 ·
What a mess!!! reading through the original post i would say proper times and everything else was followed to the tee and I have no doubt, everything was activated properly and of most concern would be the primer as over activating can cause this but the time frame is very important as well as humidity and i don't think this is the case at all because even then it will not just come off but takes a good chip to work it loose.

Activating the base actually increases adhesion so we know that had nothing to do with it.

With the above it really only leaves 3 possible causes:
*Primer was sanded when very fresh and then sat to long and closed up cells.
*Waterborne cleaner was still in primer pours and broke adhesion as paint dried.
* first coat of base was dry sprayed or covered from over-spray if other parts of car were painted first.

My best guess would be primer closed up but the big flakes are acting like trapped cleaner and that confuses me, so I wonder could it be a combination of 1 and two 2? It kind of sounds like it.

You mise well bite the bullet and lay some two inch tape on the other panels and snatch off to see if you have adhesion in those spots.
If you do, that kind of points to 1+2 on the doors.

This is the best I can come up with but let me know and let me know what you need to finish doors up, if you are running short.
 
#27 ·
On one of the threads we were talking about dumb mistakes we did in and around the paint booth over the many years some of us have been painting !! and one that came up a few times was adding a material from a can other then the one you thought you were adding especially when tired from hrs in and out of the booth! Especially when cans look alike with my age now I use tape and a marker and label my cans and when mixing on a note pad I write down what I just added!! I also write down what time I enter the booth and when I come out and what pass I just made LOL:D I dont know how many times over the years I answered the phone came back a few minutes later and forgot what I just added or thought is this my 5th or 6th passLOL:pain: and poring out the questionable mix and starting the mix over LOL I always order extra material:thumbup: ! But if you dont catch it and shoot you think everything is perfect till the next day LOL:pain::drunk:

Over the years Ive caught it just at that moment except once I was using material in cans that all looked the same and my wife just used the thinner to clean some bare metal in the shop before etching and she sat it on my mixing table and I grabbed it and used it as enamel reducer I went in the booth to shoot my 3rd heavy pass and man my wife's holding the hose behind me and yelling for me to stop somethings happening to the paint!!!!!:eek: the top of the quarter wrinkled like a fat woman's A S S and started falling off the car :pain::confused::eek::drunk::drunk: I opened the cup and could smell the lacquer!! ran out to the mix table and saw the can :eek: I immediately blamed her and the :boxing: was on!! But it was my fault I was tired and not paying attention. Im sure all you older painters can relate LOL

Chris
 
#28 ·
What about sabotage? I worked at a shop with four painters and the #1 didnt like it when his talent was rivaled he would add something to the W&G or the clear ,I wont say what because there are those that would do it.
I'm still thinking its the activated base but the water born W&G sounds like a good runner up,have you used activator in this base before?
 
#29 · (Edited)
I have thought about this non stop, every problem has a set of reasons, if first week in sun you get 4-7 bubbles here and there on the car, can be one set of reasons and if you get just bubbling on hood and deck lid can be another set of reasons.
Undried wax and grease removers will case certain problems, solvent trap-age another, mis-activating the substrate another but none of these causes paint to come off in sheets, like this. Easy chipping, poor adhesion, dieback, yes but not sheets.

The base worked great on the other parts of car but not doors, the base is not smart enough to say, I think I will screw up on these two panels and do OK on the others.--SO the base is perfect.

That only leaves something "in" the last application of primer or something "on it". Whatever it is, is extream, too cause this.
The primer must come off, as nothing will ever stick to it.

Paint just don't come off in sheets over primer, even if it was over activated, under activated or sanded with 3000 or not sanded at all, or closed up do ue too setting, even undried wax and grease remover the base will draw out and dissipate and you may see popping or fish-eyes but it still will not come off in total sheets, maybe a 2 inch spot and prone to chipping but not sheets.
 
#30 ·
Yep, there are patterns to most every failure. When you are dealing with problems every day in shops all over the place as when you are in the paint business there are patterns, they are so obvious it isn't funny. Same as in the collision business you can look at a car and tell the owner how it happen before they tell you, there are patterns that because so clear and cut and dry it isn't funny.

This one most certainly doesn't fall into any one common pattern. It is odd, after seeing failures day in and day out for years and you don't see something like this I can see it being in your mind non stop Barry, it is an odd one.

I still can't see it being anything but the perfect storm.

I remember I laid a stripe on an S-10 truck once, it went all the way around the truck in HOK candy. Now thinking back my mind gets cloudy on just what the problem was, but it was peeling or severe die back or something. Anyway the failure was directly related to a time issue, where as the portions of the stripe that were applied over the primer the soonest failed where as the stripe over the primer that last applied worked fine. It was as clear as day that the application time had EVERYTHING to do with the failure. All within one stripe! So the planets can be aligned on one area and not another.

Then stuff comes out of blue. I had a Ford truck that failed BIG TIME. We are talking a SS acrylic enamel complete that was striped to bare metal and primed. Sealed and painted, about a year later he came back and the paint was CHAUK! You could literally put your fingernails into it like a bear claw and scrap the paint off with your nails! Now the odd part, it was a color change. The door jambs and underhood were all perfect! Then it hit me, I had a test panel that I had painted and thrown up on the roof. I went up there and got it and you guessed it, PERFECT. WTF? I did a little detective work and found out from a friend of his (we are talking detective style fact gathering here, the guy didn't rat on him) told me he had waxed it with a sealant style wax at just a month old!

I refunded him his money but wasn't about to repaint that truck.

Every odd one, if you are there looking at it and are able to ask many questions and SEE how things are done you can usually figure out even those odd ones. And it's an easy to get passion to figure them out isn't it Barry! You get a high tracking down the cause. :) I can certainly see why it has been on your mind, it's hard to forget about one like this.

I am still thinking it is simply a perfect storm with just the perfect solvent entrapment and wax and grease remover soaking in kinda thing. Something made a "barrier" between that primer and paint! No lack of sanding could do that. You could paint right over an unsanded hood that was cleaned properly and not have it come off in sheets like that. There was a barrier, there was SOMETHING between the primer and paint, like a sheet of saran wrap laid over the primer and then painted on, there was something that totally separated the primer from the paint. No lack of sanding or hardener in the paint is going to do that! (I still will recommend never to mix products though). Nope, something is between the primer and paint, and the only thing this could be is solvent of some sort.

Brian
 
#31 · (Edited)
Yea Brian, we both have been through it and heard it all and sometimes there just are no reason for something that happened.

My favorite one:
About 3 or so years ago a shop from the Midwest called and up front, said He was a restro shop used PPG and would never use my product but would I help him with a problem and of course I did.

He had done a car and two weeks out the door, the LF epoxy is coming off in 3" to 1' sheets with just the slightest pressure. The factory PPG guy came and said either contamination on metal or solvent trap in the epoxy.
The shop owner just knew, it was a bad batch of epoxy.

So this guy starts the blow by blow and I slipped in trick questions on each product, just to verify he had no defective products.
Everything was just perfect, product wise and flash time as well as prep wise.
30 minutes later he was done and my answer was, sir you did everything perfect and overkill all the way throughout the job and a lot of the questions I asked you were questions for myself to see if, you did have any problem products and I can honestly say you do not as i have no reason to protect PPG.
So I'm telling you now, what you say happened, could not chemically happen with the info you gave me and it did not happen.

Then he said! OK what if I had use this product after the car was sandblasted?
I said we could have saved 30 minutes of conversation.

To this day, never talked to him again but I will put money on it talking to this guy after he beat the poor PPG rep half to death, he NEVER did call and let the poor guy know what caused the problem.
Oh the reason for this strange product on the metal was the owner brought a gallon in and insisted because he read how great this stuff worked and Like a, I told the owner of the shop, you better hope the customer signed something for using this product because, he is not going to want to pay to have you redo the job. Got real silent at that point!
 
#32 · (Edited)
LOL, one of my favorites was talking to a customers customer, the guy that owned the boat trailer my customer had painted. I learned stuff from the customer to repute what the owner had told me, funny stuff. Another time I had a guy who use to screw with ratios all the time. He had a customers truck that bird crap had attacked the paint. He was telling me how the paint is junk and on and on. I went and got a lacquer thinner rag and rubbed it on a spot at the bottom of the fender and in two or three passes I went to primer! The paint had ZERO solvent resistance! With the shop owner in tow I walked into the shop and where there was a tailgate that I had painted the day before. I poured thinner on the rag soaking it and rubbed as hard as I could on the tail gate, NOTHING, it didn't so much as take any gloss off, you should have seen his face.

Like I said, I KNOW you Barry and this one has been in your head, you are that type of guy like myself who WANTS to know what happened.

Brian
 
#33 ·
Something I've done on more than one occation when I'm rushing is add the wrong ingrediant to something I'm mixing if my bench gets clutterd and I grab a can of something thats in the wrong spot.
The FIRST thing I start thinking about if theres a problem is what did "I" do wrong because in all the years I've been at this I cant think of one time it was one of the products being at fault it was always me. after you've mixed thousands of gal you start doing it without thinking and thats where you run into trouble. A clutterd up paint bench is my biggest reason for trouble ,I have to keep everything up on the shelf and only what I need on the bench,so when basing theres the base and the reducer on the bench ,thats it ,when I start the clear everything goes back up on the shelf and only the clear ,hardener and reducer is on the bench. being a bit of an air head can be a problem but you can learn to get around it.
99% of the time it'll be human error thats the culprit,in my case anyways...
 
#34 ·
I did a beaut about two years ago, when I restore a car, I tend to get stupid, like the inside of the doors, even thought the factory just has over spray there I base cleat the whole inside.
So I have the vett doors laying on stands and its Sunday and I get a tech call as I'm mixing the clear, so talking on phone and activating clear, like an idiot and activated it with reducer, shot four coats on each door, after dinner went out and clear is still wet.
You would have thought I would have known better. LOL
 
#36 ·
It is probably better today but 25 years ago it was really hard to get the old timers to learn the technology that went along with the new catalyzed systems. Some of the concoctions people used were unbelievable or else they would say "that is the way I always did it". You couldn't hardly get someone to read a spec sheet. I painted my first Catalyzed paint in 1978 or so. It was S/W acrylic enamel with Polysol catalyst and that got me fascinated with the "new" technology. As a matter of fact I still am. By the way, I parked beside that same S/W paint job tonight at the Sonic.:)

John L.
 
#38 ·
Yeah John, there are still plenty out there that REALLY think they are smarter than the manufacturers tech dept! This one customer of mine, he was what we called a "Junior Chemist" and he TOLD the tech rep when I brought him in how the company was wrong and there was too much hardener! He would do the damnedest things. Like Barry was saying there are patterns, you can't believe how clear these patterns are. I walked into this Junior Chemists shop after being called about a problem. I walked in there, looked at the car and I told him EXACTLY what he did, how he sprayed it, the number of coats, the reducer he used I told him EXACTLY what he did like I had been watching him thru the window! His jaw dropped, he couldn't believe what he was hearing. LOLOL

Brian
 
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