Paint Prep

[dclewallen]

I've got a paint question. My 53s at a shop having the few dents repaired and also being trimmed out for a color change, After this is done I plan on taking it to my uncles for a good exterior paint job. My question is, the car has two paint jobs , the original then a primer coat and another coat of a different color on top of that. I am planning on just removing the paint and primer down to the original paint and stopping there. The paint appears to be in decent shape [no cracking, etc.]. Does anyone forsee a problem with this approach? Thanks for any input.

Darryl C. Lewallen

[gotti210]

well my first question is how do you expect to remove just the latest coat and the primer coat but not the orig

if you used paint stripper it would remove everything and if you just simply sanded it that would be alot of work to only remove one of three coats

my suggestion is if your current top coat is in fairly descent shape

wet sand the whole car with some 400 or 600 grit paper and light coat it in primer and paint it

next step----- drive it and enjoy it

[Jerry Johnson]

[studegary]

My opinion is to strip the car down to steel and then start with a metal etcher. One '53 Starliner that I painted was a car that I knew since it was new. One door and fender had been repainted long before due to accident damage. The original enamel looked good and solid. I decided to strip the roof. I was surprised to find that the metal surface under the paint appeared to be (slightly) rusty. I am glad that I got down to bare metal. This eliminates the possibility of ruining an expensive paint job by leaving some unknown under the new paint. I painted that '53 Starliner with nitrocellulose lacquer (seven quarts before thinning). The paint job still looks excellent more than 30 years later. I guess that it was worth the effort to do it correctly the first time. There is an old saying that goes something to the effect; Why do we not have time to do a job correctly the first time, but always have time to to do it over?

[Roscomacaw]

Let me tell you what I've just experienced in my first-ever attempt at painting a car.[}]

With the local paint store guy holding my hand (in essence) as I prepped my 58 wagon for a recolor, I sought his advice as to whether or not I could safely paint over the original paint and expect good results. His answer was an unqualified YES if I sanded carefully and then used a sealer before applying the base coat, clear coat, finish.

I prepped more than any paint shop would have with respect to the finer details that I wanted to see come out nice. Once I got brave enough to load my shiny new paint gun (a marvel of a gun it is too!), I laid on the sealer and was a bit dismayed that it had a rough texture on the very upper part of the roof. Other'n that it had laid on nicely [:I]
I wet-sanded the rough part with 400 paper to my satisfaction and then taped up the car and shot my 2-stage finish on it. I was using quality paint too, PPG brand, not some cheap junk.
The color laid on with relative ease, considering my lack of experience at the task. Because of the height of this car and the loooooooooooong roof, I had makeshift scaffolds on either side of it so I could effect, long, even passes with the gun. It was still kinda shakey - treding to and fro on the 2X12s I used for walkways![:0]
But - it went on nicely - the color coat. And I quickly followed with the clear and that too went on with relative ease. But after the second coat of clear, a long bubble rose up from under a rear part of the rain rail. I was mystified as to why it would do such and I decided to wait and see if the swelling would go back down as it dried some. Alas, it did not. I therefor cautiously pricked a hole in that rising and found that there was no fluid or anything behind it but only whatever solvents it must have trapped.
I tried pressing the bubble back down with a finger, but the film of paint had dried so well that it simply cracked in jagged fashion and looked like.... well.. you know.
Other than that and one other smaller bubble like it, the sucker looked REALLY nice for my first attempt. I figured I'd let it cure for a couple weeks and then I'd color sand it to where it had a nice gloss. And it was already looking as good as any Macco job I'd ever seen![8D]
The weather's been nice here and after two weeks I decided to try and spot that bubbled place since I was gonna shoot the top portion of the doors with the same color. (The doors were off the car)
I started wet-sanding where the bubble had been forced to lay down and instead of the paint feathering out nicely, it kept curling up under the sandpaper. A genuine pisser.[xx(] I finally started digging at the edges of the paint with a fingernail and I found how easily I could peel off my pretty layer of color with the sealer attached to the underside! In fact, what was still underneath the peeling paint was now gummy goo!
SO - I gave myself an A for application and an F for frustration. Other parts of the car, the paint appears to have stuck very well. But I'm thinking now that I may be forced to strip the rear quaters at the very least and take them to the metal. It looks as tho the sealer didn't grab onto the well-sanded original finish. Maybe even aggravated it!
My paint guy's without an definite answer (and he's been selling and using the stuff for ages) but I can't help but wonder if I'd just used the 2-stage paint right over the old finish and forgone the sealer! I sure hate to have to strip the damned thing. Of course, no one likes steping backwards.[V]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

[Kdancy]

On an old car, I never take the chance on painting over the old finish even with sealer. You just never know what old repair might have been done or what is under the paint. Much better to just take the old stuff off and apply a good epoxy primer. Since I started making that common procedure I've not had any problems with adhesion. Good quality paint just cost too much to take the chance.

53commander HDTP
53 Champion HDTP
61 Cursed Purple Hawk
64 Champ long bed V8
64 GT

[52hawk]

Mr Biggs,1 mistake-you say you 'quickly' applied the clearcoat.
You have to let the color coat dry out well before spraying the clear.Time between coats is important. PPG recommends dry-time according to how many coats of color you apply,-I think about 20 minutes.[So if you applied 3 coats of color,wait at least 60 minutes to clear,and so on.
On important paint jobs,I let the sealer dry overnight,colorcoat in the morning,clearcoat in the afternoon.
Usually rushing the process only causes 'dying back'of the clear.[that means the gloss dulls out in a few days,needs more buffing.]but can also cause 'solvent pop'-sorta like you describe.

Home of the Almostahawk

[DEEPNHOCK]

Sounds like you suffered from 'bounce'...
If the next coat goes on too quickly, the solvents in that coat soak in and 'bounce back' and try to come out to evaporate. If the coat has skimmed over, then the solvent can push the top coat out (like the bubble you described)..
PPG has a way of getting you to use 5 times the material an old paint job used to take... You can actually sand the color coat before applying the clearcoat.. You do have some time between paint top coat and clear coat. Most shops now cook the coats to speed up the process. Without an oven, it takes a while to let the solvents evaporate.


[quote]quote:Originally posted by Mr.Biggs

Let me tell you what I've just experienced in my first-ever attempt at painting a car.[}]

With the local paint store guy holding my hand (in essence) as I prepped my 58 wagon for a recolor, I sought his advice as to whether or not I could safely paint over the original paint and expect good results. His answer was an unqualified YES if I sanded carefully and then used a sealer before applying the base coat, clear coat, finish.

I prepped more than any paint shop would have with respect to the finer details that I wanted to see come out nice. Once I got brave enough to load my shiny new paint gun (a marvel of a gun it is too!), I laid on the sealer and was a bit dismayed that it had a rough texture on the very upper part of the roof. Other'n that it had laid on nicely [:I]
I wet-sanded the rough part with 400 paper to my satisfaction and then taped up the car and shot my 2-stage finish on it. I was using quality paint too, PPG brand, not some cheap junk.
The color laid on with relative ease, considering my lack of experience at the task. Because of the height of this car and the loooooooooooong roof, I had makeshift scaffolds on either side of it so I could effect, long, even passes with the gun. It was still kinda shakey - treding to and fro on the 2X12s I used for walkways![:0]
But - it went on nicely - the color coat. And I quickly followed with the clear and that too went on with relative ease. But after the second coat of clear, a long bubble rose up from under a rear part of the rain rail. I was mystified as to why it would do such and I decided to wait and see if the swelling would go back down as it dried some. Alas, it did not. I therefor cautiously pricked a hole in that rising and found that there was no fluid or anything behind it but only whatever solvents it must have trapped.
I tried pressing the bubble back down with a finger, but the film of paint had dried so well that it simply cracked in jagged fashion and looked like.... well.. you know.
Other than that and one other smaller bubble like it, the sucker looked REALLY nice for my first attempt. I figured I'd let it cure for a couple weeks and then I'd color sand it to where it had a nice gloss. And it was already looking as good as any Macco job I'd ever seen![8D]
The weather's been nice here and after two weeks I decided to try and spot that bubbled place since I was gonna shoot the top portion of the doors with the same color. (The doors were off the car)
I started wet-sanding where the bubble had been forced to lay down and instead of the paint feathering out nicely, it kept curling up under the sandpaper. A genuine pisser.[xx(] I finally started digging at the edges of the paint with a fingernail and I found how easily I could peel off my pretty layer of color with the sealer attached to the underside! In fact, what was still underneath the peeling paint was now gummy goo!
SO - I gave myself an A for application and an F for frustration. Other parts of the car, the paint appears to have stuck very well. But I'm thinking now that I may be forced to strip the rear quaters at the very least and take them to the metal. It looks as tho the sealer didn't grab onto the well-sanded original finish. Maybe even aggravated it!
My paint guy's

[Roscomacaw]

That sounds plausible, Jeff. Although I waited maybe 45 or so before hitting it with the clear (and that's when it bubbled) (and it was 85 degrees out)(and I was using the prescribe reducer for that temp rqange), I did lay on succesive coats of clear in quick fashion.
Ya know - it wouldn't have been so damned disappointing if I hadn't managed to lay the stuff on so slick! Other'n that initial bubbling, it looked great! But further inspection reveals that the color coat's not holding to the sealer at all. And I asked specifically if I had to sand the sealer before I put the 2-stage stuff on. The answer was "no". Now I think maybe I should have.[V]
The lower color (a light blue) I shot on the lower part of the jambs and just went right on over the original finish after lightly sanding it. It's stuck like glue on that original finish![}] Go figger![8]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

[studegary]

You can't compare painting jambs over old paint to painting the rest of the car. The jambs normally aren't exposed to wax, polish, silicon (that gives problems for a long time), weather, etc. On many cars where a color change isn't done, the jambs only need a cleaning.

[dclewallen]

Thanks guys for all the input on this. I'm mechanicaly capable but when it comes to paint and the changes that have taken place in that field I don't know much[?]

Darryl C. Lewallen

[Kdancy]

quote:Originally posted by 52hawk

Mr Biggs,1 mistake-you say you 'quickly' applied the clearcoat.
You have to let the color coat dry out well before spraying the clear.Time between coats is important. PPG recommends dry-time according to how many coats of color you apply,-I think about 20 minutes.[So if you applied 3 coats of color,wait at least 60 minutes to clear,and so on.
On important paint jobs,I let the sealer dry overnight,colorcoat in the morning,clearcoat in the afternoon. Usually rushing the process only causes 'dying back'of the clear.[that means the gloss dulls out in a few days,needs more buffing.]but can also cause 'solvent pop'-sorta like you describe.

Home of the Almostahawk

I started the overnight sealer dry some time ago. It gives the solvents time to evaporate some what. Next day, I apply one coat of sealer, wait 20-30 minutes and apply base. Haven't had any issue's since I started doing this several years ago. Now if only I had a heat controled booth!

53commander HDTP
53 Champion HDTP
61 Cursed Purple Hawk
64 Champ long bed V8
64 GT

[52hawk]

I have a 2 year old cross-flow booth.Not state of the art,but I'm happy with it.For the volume of work I do,a heat system is just not in the budget..Incidently,my booth is built by ColMet.The large stickers that came with it say CHAMP SPRAY BOOTHES. !!!!


Home of the Almostahawk

[Roscomacaw]

Good Gravy! Does that mean you'd hafta buy a Hawk booth just to paint one[?][?][?][8]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

[52hawk]

No,the Hawk fits in the Champ! I have some Transtar primer,but used PPG on the Hawk.


Home of the Almostahawk