So, the car is back on the road after its collision with a Titan(ill post pics tomorrow), I picked up the parts, replaced the front inner aprons and radiator support. By the way, I hate spot welds. I have stripped and primed the fenders in a dupont 2k epoxy primer and am thinking of painting the entire car instead of just the front cap once I get the hood straight.

I have a booth to do it in, I just need to know If I could do spot repairs on the body (sand, fill/skim coat, prime 2k) and then scuff the rest of the car with a grey or red scotch pad, or if I should just wetsand the entire car with a 500 (?) grit long block and then be able to apply a new base/clear over that. The paint on the car is only 4 years old, but has seen lots of sun here in hawaii and salt air, and there is just something in the rain out here that kills paint. Waterspots everywhere.

I thought about just blending the color from the front cap to the rear, but with that I may as well just re-clear or repaint the rest of the car too.

Please give me your suggestions on repainting the rest of the car. I found a rattle can 2k primer at Napa, that could possibly work if I need, but I do have more dupont 2k for any spot repairs.

 

if you plan to paint the entire car, then make sure you get the final prime (or seal) in one consistent color.

as far as what grit, refer to the p-sheet or tech sheet for whatever you plan to spray as it should recommend a grit. in terms of using scotch brite pads, just be sure you have the right one (you can look up the grit for the pad) for the paint you're spraying. a red is probably on the course side if you were to spray something like a topcoat.

rattle can primer doesn't provide much film build for sanding. also i'm not sure how you can have a 2k primer in a rattle can, but i haven't really looked at the rattle can stuff.

 

As with anything it depends on how much you want to spend and what you use the car for. If it is a daily driver you should hold off on a show quality paint job. In order for a good repair and final appearance I would also avoid the rattle can primer, this primer is thinner and unless you are willing to put in extra hours it is tough to get a coat thick enough for a good blocking.

As for the rest of the car, first apply wax and grease remover as wax can gum up your paper/pad and you end up wasting material and time. If the paint is only 4 yrs old it probably is worth saving. A simple scuff and buff is done by wetsanding the car with 2500-3000 grit (3000 if unfamiliar with this method) and then simply buffing. This method removes the outer-most layer of the clear and leaves the rest, resulting in a revived paint.

Try this on an inconspicuous spot and if unsatified, blending of the sections of car is a somewhat easy process.

 

On places you want to do body work, (filler etc) an 80 grit scratch is all but essential.

Usually when I am doing a "well worn" complete that I want straight and smooth, I will BLOCK sand the entire car with 80, this will show me everywhere bodywork is needed, and if I am not taking all the old finish off, it allows me a 1st block without the expense of primer.

After this, depending on the car, I might spray 1/2 a gallon of high build primer, and I might sand (no less than a few days later) another time at 80, or I might move to 220 or 240... repeat the process, and then sand at 320, and then again at 400 before paint.

If you car is straight enough, you can start with 400 and shoot, but the biggest mistake I see people make with bodywork is to move too quickly to fine paper. Body filler should be worked with 80 grit. Fine paper will get things smooth, but smooth wavy filler ain't cool. Get straight with 80, then smooth with finer paper. Blocking with a guide coat is your friend....

Don't go finer than 400 before paint unless you are shooting a really fine metallic, then you can go to 600.

If you are going to use spray primer, 80 scratch will be hard to fill, is so, sand to 220 then prime.

1. A scuff pad works great (purple is what you want), but it wont straighten out anything.

2. get a block that is about 18" long for use over the entire car. Areas with filler may require a longer block.

3. Sanding with a block will show imperfections (low and high spots) before paint, finding them after paint just sucks...

4. When blocking, sand til you see metal, then stop. Evaluate the situation, leave it alone, or add filler, add primer, OR tap the offending metal down and fix the surrounding area with filler or primer.

5. keep filler under 1/8" thick whenever you can. Make sure you don't "make" edges with filler. Get the edges right in metal.

6. If (when) you find old filler on your car, evaluate it, if it is not too thick, and it is cot covering something bad, you can leave it in place and use it to straighten your car. The same rule of "sand til you hit metal" applies. A drill bit and/or a carefully used cut off wheel can allow you to evaluate the thickness of old filler, and to see what it is covering.

7. Lots I forgot to post....


The best, nicest, and cleanest paint booth I have ever had the pleasure of using was in a craft shop on Ft. Huachuca... I am thinking this is what you have available to you? If so, way cool

8. Oh yea, don't expect TOO MUCH fill from spray can primer. If you can afford it, 2 part primer will make your life easier. (If you go too thick with spray can (lacquer) primer, it will continue to shrink for a long time, maybe causing your finish to craze, check, or crack. Spray can primer used modestly in thin coats will work ok.

9. Primer is more of a smoothing agent than a "bonding agent". People think that primer is a needed step for the paint, not really. It is to be used to get the surface smooth for paint. (High build primer, used properly, can do some amazing things.) You DO NOT HAVE to use primer over your entire car. You can safely put new paint over properly cleaned, sanded, and prepared paint without primer. I DO recommend a good two part sealer that is close to the new top coat color over the entire car RIGHT BEFORE paint. If you do this right, you WILL NOT use a whole quart of sealer. You WILL need 3/4 gallon of paint and another 3/4 gallon of clear to cover the car, if you don't make many mistakes, and if you don't paint under the hood, under the trunk, etc. Budgeting for, and purchasing, a gallon of paint and clear is prudent.

10. ANY TIME you let paint or primer get dry, (check the can for top coating rules) it MUST be sanded for the next layer to adhere properly.

11. If you go base/clear.... You can sand and repair the base as much as you want prior to clear, if and ONLY if, the base is a solid color, metallic bases can not be sanded without a respraying the effected area. (sanding "breaks off" the metallic particles, changing the way metallic might look once cleared) I advise sticking with a SOLID color for your first car, (or 2 or 3) it is tons easier to get good results with a solid color. Take note, sanding a base too quickly may result in it balling up into little boogers that are difficult to get off the surface, be PATIENT, but be wary of flash times. (Take your time but hurry up)

12. Oh yea again.... After getting things straight with a block, you will need to get the scratches and gouges out out of the finish that the block will put in on inside curves, etc. A D/A works best for this, and a CHEAP Harbor Freight one will work just fine for a car or two... Or you can address the scratches by hand, either way, don't put new different scratches and gouges in when fixing the block scratches.

13. Buy good filler, don't buy AutoZone Bondo.... stuff in the neighborhood of $15 - $20 a gallon is what I use, (Z-Grip). Rage Gold is the bomb, but at $35 to $50 a gallon... well it ain't that good...

 

James, you are awesome. Thanks for taking the time to write that all out. I have more questions though.

Today I started blocking the entire car with 500 on a 16 inch or so block. Is that going to be deep enough for laying on some epoxy dupont 2k to the rest of the car?

I dont mind spending the money to buy the paint, its a metalic base/clear dupont 3 qts of base a gallon of reducer, and an activator for the base also. Plus a gallon of clear for about $260 here in the dupont store right down the street.

The question is, should I just scuff and shoot a new base over my existing clear coat or shoot the entire car with the light gray 2k that I still have, block it, and then base/clear it? I drive the heck out of this car, daily, but I try to keep good care of it though.

Im just torn on how I should go about getting the paint to look right again.

Im also afraid of how much base its going to take to get coverage over the light colored primer.

 

Yeah 500 will be enough, that is what we used on mine.

250 dry sand and then go back over with 500 wet sand.

 

OK. I think I will make my repairs, then prime those spots with the 1/2 qt. of 2k that I still have, then get a dark gray sealer to lay down then paint.

Can anyone talk me through gun setup. I seem to keep sagging the paint. I am awesome with a rattle can, but the couple of times I used the gun I didnt do so well. Better the second time though.

I was running the inlet pressure at 60psi the first time, and didnt realize that the gun said to use 30psi at the inlet. So I figure thats why. It shot in a pretty straight conical pattern. The next time, I lowered it to 30 and adjusted for a vertical line but still ended up with too much paint in spots. I think I may be letting too much paint out, so I will adjust the needle a little so that it doesnt back into the gun as far right? And I believe that my spray distance of about 8 inches may have been too close? Any suggestions?

 

What kind of gun are you using? Here is a great link on setting up your gun..

http://www.southernpolyurethanes.com...your%20gun.htm

Memorize this! "Orange peel is fluid adjustment and run control is an air pressure adjustment."

 

Since Im going with such a dark color base, do you think the color will really be that much different if I didnt prime the entire car and just shot the whole thing again with the front end being in the light gray and the rear being dark?

Im trying to save some cash on primer. I know I can finish what I have to fix and prime that with my remaining 2k but the rest of the car is going to take another qt.

Again. Is my dark base going to provide coverage over the light primer?

 

It will cover, but it is harder, takes more base, and not as "sure".

The problem is that you might not notice a "shadow" til you get the car out in the sun... been there...

A quart of dark grey sealer is cheap insurance, and will (imo) make your base sit down better. (in a pinch, you could get by with a pint of sealer to put over the light spots only)

Black usually covers pretty well, but it also "shows" a lot if you don't get full coverage.

The base is the MOST important thing to get right, you can fix just about anything, but it is about 10 times easier to fix clear than to fix base. A sealer will help with the base, and it will allow you a "trial run" right before you lay down the base.

In my experience, you want to use just enough pressure at the gun to get a nice spray, but not too much. One gun will differ from the next so it is hard to say just ho much is right.

With the sealer, you will want to lay down a coat that is all but translucent when wet, very thin....

When shooting a non-metallic base, don't get in a hurry, and don't try to "paint" the car, just get it covered in as many coats as you like. If you get too close, or try to put too much paint down in any one goat, you will end up with stripes, that won't fully go away after clear coating. Even, even, even. You want the car to look satin before clear, not shinny, and no shiny stripes. If you end up with stripes, you can cover them but you will need to let the base dry for a few hours, and then dust from fresh base on top to get everything back to a consistent satin. If you try to cover stripes too aggressively, (with lots of paint) the paint already on the car will soften and the stripes will reappear.