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EFI Rules and Carbs Drool
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Discussion Starter · #1 ·
I posted a couple of weeks ago about how painting the new frame for my T bucket was going well except the runs in the clear. Well, of course I tried to cheat and there were so many runs that I used an electric orbital sander to take the runs out. I worked really well actually. BUT, I was in a rush and sanded though to metal in some spots. OK, a lot of spots.

Primer- Omni Epoxy
Base - PPG 2000
Clear- PPG 3000

So
I sanded the clear smooth and reprimed the bare metal spots. OK so far. I went over the primered spots with a scotch pad. Then I sprayed the base coat over the primer. Here's were it get worse. The new base coat patches start to crinkle. I'm thinking since it was starting to look good again, I was recoated a lot of the spots too soon and the first coat of base never really flashed. If I give it a day and resand the crinkled areas, can I continue with repainting the patched areas?

I'd like to save the paint that's already on there, but I'll redo the whole thing if I have to. I'd like to save the $300 in materials I already layed down.

Thanks for any help.
 

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you basically sanded your fresh clear down to a feather edge which is very delicate then when you sprayed your basecoat on, the solvents in it attacked the edge wrinkling it up like paint stripper. ok best thing you can do is sand the crinkled areas down again and prime the areas. you didn't mention what kind of primer you were using. you will need a 2k or epoxy type. these (when cured) make a chemical barrier against the fresh clear. you might want to spray an epoxy if your down to bare metal again then a couple coats of a 2k and block sand because you will most likely see the burn through in the final finish if you dont, but also dont sand the primer too thin, thats your barrier. let the primer cure atleast a day but longer is better. rebasecoat the areas. use fast reducer and go SLOW!! put one coat on, wait 1/2 hour or so then the next. dont make them heavy. you should be ok.
 

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EFI Rules and Carbs Drool
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Discussion Starter · #4 ·
mrcleanr6,

Thats kind of what I was afraid of. The thing is, I did cover the repair areas with epoxy primer and then shot my base coat. Not all the areas did it so I'm thinking it was in the application where I messed up. That brings up another point. There are more areas that I sanded through the clear, but not the base coat. My plan was to cover the patch areas to get the correct color match and then spray the another coat or two of base coat over the whole thing and then try the clear again. Will that work, or will the clear lift in areas that are sanded though?
 

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there is always a risk of wrinkling when bascoating over clear that is very thin and fresh. the longer you wait and let the clear cure the less chance you have of this happening but even if it is pretty cured, if you put the basecoat on heavy then it will still do it. best recommendation i can make is spray a coat or two of epoxy over the known areas, let cure for atleast 24 hours, use a fast reducer, spray light coats of base and let each coat flash for atleast 45min or more between coats. its the reducer in the basecoat that does it so you want to get it off the surface as fast as possible before it soaks in to the clear. of course spraying in a warm enviorment helps speed up the flash too. if its cold where you spray then you might want to take a heater in and warm up the body of the car too then shut it off before you spray. if you follow as many of these steps as you can you should be fine.
 

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EFI Rules and Carbs Drool
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Discussion Starter · #6 ·
Well, to complicate things further, how would I apply grahics over the clearcoat? Let say for the sake of argument that I get everything fixed up and I get a couple of nice clear coats on. If I want to add some flames or something, will that pull up the clear again? Would I have to spray a sealer first?
 

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no, you will be fine since there will be plenty of clear on the surface. just lightly wetsand the clar with 600 to remove 70% of the orange peel and then scotchbrite the surface with a grey pad to completely dull it out. you usually only have these problems when the clear is super thin or out to a feathered edge. of course you still want to make sure you let it flash a while between coats. dont go spraying your base wet on wet.
 

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EFI Rules and Carbs Drool
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Discussion Starter · #8 ·
I sprayed another coat over the patched areas and it flared up again, but the paint seemed to calm down overnight. I think I am going to try to work with it and give it time between coats and see if I can build it up. I'd really like to save the paint I put down so far. I'll get more base coat next week and try again. The areas are actually on the bottom of the frame so I'm not going to get all crazy trying make it perfect.

Thanks for your help
 

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bubbling paint

try to mist on the first coat . i mean light mist
let it dry up maybe 45 minutes .
then do it again.
once you have the area covered you can start laying your paint the regular way.
 

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Brian Martin,Freelance adviser
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Hoss has the idea, remember it is the solvents from that next application of base or clear that will attack the feather edge and get under the base or clear you have sanded thru.

If you use a "faster" reducer, spray it drier (the "Mist" Hoss refers to) get the frame warmer, SOMETHING to slow down the amount of solvents that can soak into that feather edge. It would blow your mind the amount you messes you can save by "misting" that base or clear over these problem areas. You need to build up a "barrier" of base or clear and allow it to flash off well. That will keep the solvents from a wetter coat from soaking into that feather edge.
 

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EFI Rules and Carbs Drool
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Discussion Starter · #11 ·
Well, that seemed to do the trick. I was able to save the paint job and now everything is clear coated. I did end up with some more runs though. Man, that clear is tough to spray.
 

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Shop Owner And Troll Hunter
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Don't apply heavy coats of clear and it will not have runs.

Troy
 

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EFI Rules and Carbs Drool
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Discussion Starter · #13 ·
Well that's pretty logical, but there must be something I'm doing wrong because there seems to be a very fine line between geting the clear to flow and having a smooth finish or having it too thick to the point of where it runs. Maybe I'm not setting my gun up right.
 

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Shop Owner And Troll Hunter
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It's called experience, and it dosn't happen over night.

Troy
 

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Brian Martin,Freelance adviser
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Arrowhead, have you read this (click here) ? It may be of help.

Spraying frames and similar items is taxing even to the most experianced painter. Don't feel bad, it is very easy to get a run on these irregular shaped parts the lots of nooks and crannies.

A few things to watch out for are first off, don't narrow your spray pattern much. I remember having a guy show me how to paint a motorcycle frame back when I was a kid. He showed me how you narrow the pattern down to only a few inches so there isn't a lot of paint blowing past the frame being wasted. He also would turn the cap so the fan would spray horizontal when he sprayed the vertial tubes. Luckily I soon would be able to watch others paint to find out these suggestions were all wrong. At least, never done by any painters I had ever seen and I never use these techniques as well. Well, at least not to any great degree. Sure, here are times you use them, but not to any great degree by any means.

So, paint it like you would a fender, a normal 8-10 inch fan and just swing the gun with your hand anyway needed to get the paint and clear where you want it.

The following tip is probably the most important, and the hardest one to learn. Don't apply more clear to any one area. With each coat, ONLY apply that ONE coat EVERYWHERE. Now, that is darn hard to teach doing a fender, so on a frame it is REALLY hard. But that is the trick.

That paint and clear should be able to be mil checked and find it almost perfectly the same thickness at any point on the part.

Picture each coat as being a sheet of plastic gift wrap. You ONLY want one layer with no overlap of this gift wrap. So, you lay one layer up to a certain point and then when you lay the next sheet to meet up with it you don't want it to overlap. So when you are done the entire thing has exactly the same amount of layers on it.

Now, this is not to be confused with "overlap". Your passes with the gun have to "Overlap". I am refering to the layer of clear you create WITH that over lap, it shouldn't be "overlapped" again creating twice the thickness.

On that frame, you should shoot for almost no overlap with your passes, because whether you try or not, you WILL get overlap because of the small size and the angles you are painting. In other words, one pass will easily cover the side of the rail, don't spray it too wet. You would then hold the gun at a right angle TO THE EDGE OF THE CORNER and get that, the overspray off the side of pattern will re-wet the side, apply the perfect amount on the edge of the corner and then get a nice semi-wet start on the bottom. The pass following it on the bottom will re-wet the "overspray" from the pass you made on the edge and without any trying what so ever that edge will get "re-wet". If you "try" to get some more on that edge, you WILL end up with too much there.

This gets very, VERY tricky when you are painting crossmembers on a frame. As you get to the end of the crossmember where it welds to the frame, you have to REALLY watch how much you apply, keep it light, VERY light as you get to the end of the crossmember. A LOT of "overspray" from that crossmember will be DIRECTLY applied to the side of the frame where the crossmember welds to it. WELL, when you spray your pass on that side rail you CERTAINLY don't need any more there, you already have your "layer of plastic" there. So, when you come back and spray that rail you DO NOT have to get back in that corner where the crossmember welds to the rail, or you WILL be applying too much there.

As a kid I worked in a full on restoration shop as a painter. I would paint frames and the like all the time. The owner of the place taught me an interesting concept that I have used throughout the years. "Move your dry spot around". He didn't mean to teach me this to paint frames, but rather painting lacquer completes. When painting fifteen coat lacquer paint jobs, if you keep ending every pass on every panel exactly the same you end up with a dry spot that builds on it's self and you have this one area with different texture,and amount of paint. An example of this is right where a door meets a fender, 15 coats all stopping right at that seam, you have a super duty dry spot.

Well, this training helped me to learn how to put an even layer of paint (or primer or what ever) on the entire thing.

You can "move the dry spot" around with three coats in exactly the same way. When you see a candy paint job where the color is darker at different points on the car, this method was NOT followed. Those dark spots are proof, he applied to many "layers of the plastic gift wrap".
 

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Shop Owner And Troll Hunter
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troy-curt said:
It's called experience, and it dosn't happen over night.

Troy

Yeh, thats what I said.

When i'm painting small parts, or cross members, frames etc. I narrow the fan, decrease the guanity and go slower. That way I can control the pattern and put it where I want it. And don't try to put enough on in one coat to hide or be flowed out, like I said this will come with experience. You can watch a hundred painters paint and you will probably not paint exactly like any one of them.
Every painter does every thing a little different to make it work for himself. It will come out the same in the end with a little practice.

Troy
 

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EFI Rules and Carbs Drool
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Discussion Starter · #17 ·
MARTINSR,

I think you hit the nail on the head. I don't think I was paying attention to the areas I had already covered and covered them again when painting an adjacent part. Any runs did seem to occur near a bracket or corner. I also painted most all the suspension parts, which were mostly straight pieces like wishbones and the axles, and they turned out fairly well. I also noticed the runs mainly occured on the second coat of clear, the first coat layed down smooth with only a couple. Maybe I didn't wait long enough for the first coat to set up. Or, maybe the first coat is "slicker" than the base coat and the clear runs easier on the second coat.

Oh well, I'm learning and it is comming easier. I did invest in a new gun and that made a word of difference.

Thanks for everyones input!
 

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a couple tips that you might use in the future. one, your primer and basecoat application can tell you alot if you pay attention. use it as a tool to tell yourself how to spray the part. in other words, say you have a primer gray part and your getting ready to spray it with red basecoat. you want to basecoat to cover evenly, right?? so as you are spraying watch how it goes on. on the first coat or two you will be able to see the areas you are overlapping too far, not enough or where there isn't enought spray reaching. take mental notes and make corrections in your spray pattern now. its alot easier to see uneven coverage on color coats rather than clear, atleast on the first one or two. if you rememerber how you sprayed the base then spray the clear the same way. this should help in making too many over wet spots in the clear. another tip is after each coat of clear is sprayed and you think its flashed enough for the next coat, ever so lightly touch the masking tape somewhere right near and edge and pull your finger away. as soon as the clear stops stringing or sticking to your finger, its ready. i usually like to be able to lightly slide my finger across the clear without sticking to it. now, this works if the clear went on even, if not then you will have areas that you can touch and areas that are still sopping wet.
 

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After you do all the above advice, if you are like me you will always have a run or two on a full car paint job. I actually default @ slightly too much paint in some areas and accept self induced runs 'cause I think it is a bunch better to fix a drip than try to repair a thin spot in the paint.

If you do get a run, don't sweat it. Let it dry and fix it when prepping the paint for polishing. Look at the method I use to fix runs in my journal. Wiht just a little care, this method eliminates 100% of the flaw without damaging surrounding paint.
 
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