Why did my clear coat turn out matte instead of glossy, and how can I fix it?

Question

A while back I fixed up some rust spots on stone kicks on my hood, and ended up repainting my whole hood to cover them up after grinding/puttying/priming. I got custom matching spray paint made and used that to paint to hood, and then covered it with two coats of clear coat (I used two since the first coat wasn't glossy and thought maybe the second would be). The guy at the auto store told me to use the following:

After it was all done, it looked like a matte finish rather than the glossy coat on the rest of my car. Since the can said "high gloss finish", you'd expect it to be glossy.

I got another can from the same company that says "Acrylic Enamel" instead of "Automotive Paint", since that's what the person at a different auto store said to get (she said to just sand it a bit and spray the enamel right on top). It also says "high gloss" on it. I've become a bit skeptical of the advice of auto store people, so before I spray that on top of the previous coat, I just wanted to check with the friendly folks on the internet to see if this will actually fix my problem.

Below are two pictures of what my hood looks like now, compared to the rest of the car. You can see that the reflective gloss is absent on the hood.

Here's a photo of the new stuff I want to use:

Answer 1

@IHNIWID ..

Yes, the "color" coat(s) need to be wet-sanded aka "color sanded". And then thoroughly cleaned of sanding dust. This needs to be perfectly smooth before clear, even if it appears dull. The quality of a mirror, for instance, is not as dependent on the glass as much as the overall flatness of the silvering reflective coating or layer. I'm not a body guy, and I learned that expensive and laborious lesson too late from a real pro -- after experiencing much poorer results than the OP. I vowed not to attempt such foolishness again without guidance. Art and experience, not so much science. I was sure clear would make it perfect. It was worse. And black, the trickiest of all.

Silver is also finicky. One reason is the metal flake to make it silver will lay differently depending on the state of electrostatic charge. OEMs paint cars with all panels completely electrically grounded to minimize variation. But there still is some.

Also, there is just no way a Duplicolor rattle can is going to perfectly color match an expensive PPG or BASF (is that a VW?) factory formula at $300 a quart. UV ages paint as well, the color shifts, and the spray can has no way of knowing. Plus, no OEM uses enamel much anymore... they are much more sophisticated urthethanes and other polymers, which can't be shot out of a rattle can nozzle easily, and also contain isocyanates and other super-nasty solvents too toxic to be deemed available to public retail -- that might spray in their driveway next to the kids and dog without a respirator and a downdraft booth. (no offense to the OP intended-)

Also also, the OP set himself up with a difficult challenge. By painting only the hood, his paint job is laid directly adjacent to OEM paint on the flat top part of the fenders. That makes a very easy instant visual comparison, making the slight difference very obvious. Even a pro would probably not attempt that... while much more expensive, the fender tops would also be stripped, and the color coat blended to the outside fender edge where it rolls over to vertical. Any color difference or gloss difference would be obscured as the light angle is different. To the eyes and brain it would just seem like a shadow and dismissed. Take a look at the two OP results pictures and you'll see instantly what I mean.

And lastly, I honestly think it turned out very well. My attempt was in a clean, temperature controlled shop environment, with expensive paint, cleaners, and a huge amount of prep work. And it looked awful. Because I didn't color sand before clear.

Answer 2

The likely cause is that the paint was applied too thin per coat or the nozzle was too far away. A coat thick enough to get a glossy sheen is seen but not too thick that runs develop is the proper technique. Practice on a similar surface is suggested. To fix it, sand the surface back to smooth with 600 grit sandpaper and then re-spray with three coats about 15 minutes apart.

Answer 3

Based on what Ben said (in a comment to my original question), I wet sanded it with 1500 grit, and then used a buffing/cutting compound (Meguiar's ultimate compound) and a LOT of elbow grease to buff it smooth. It still doesn't quite have the gloss of the original paint job, but definitely an improvement from before. It's noticeably less matte, and actually has some gloss to it now. It would have probably looked a little better (and more even) if I used an orbital buffer, but I didn't have one available.

As SteveRacer mentioned, it may also have looked better had I wet sanded it to smooth it out right after painting, but I didn't want to paint it all over again to find out.

The picture below shows my newer results.

Answer 4

If your not going to use clear coat it won't get a mirror shine since you only get that before you sand with epoxy I hear. However you can, I will explain how to do it. Once the paint surface is totally smooth and you have not created any deep scratches by anything under 1000 grit ( which is easy to do if you don't ramp up the grits). Never go under 1000 unless your very good. I use meguirs diamond cut 2, then using meguirs dual action polisher to get it pretty smooth. Then apply meguirs machine gloss, that basically acts as a thin coat of clear. Then use a sealer such as cquartz or others which will help to lock in that layer and add the depth and specular ( reflection ). Put about 10 coats of sealer on and it will shine like it was cleared because essentially you have cleared it. Probably better to use clear.

The best clear is SPI euro clear it is 130 usd a gallon. It requires a lot of research to do and some basic tools, compressor hplv gun. Which may seem daunting but really it is not so much. If it comes out bad you can always polish once you learn the skill.

Plan to put about 100 hours in if your like me and don't listen to anyone and just like to learn the hard way. Hard way is the best way just takes the longest. I now understand the fundamentals of bodywork and polishing better than just following directions which is ok because I enjoy puttering around on my car experimenting.

Epoxy paint needs a lot of coats to do a hood I learned, so really it is not that cost effective. Maybe 6 cans to get it really thick so you can then go nuts polishing it to mirror like finish. It leaves a lot of overspray and peal than needs to be sanded at 800 1000 1200 then wool pad to cut that down and cut then foam pad to remove swirls. That is pretty much it listen to this and save my last 30 hours of work.

Answer 5

If you're at an amateur level with autobody and paint work, and you're trying to repaint your vehicle with automotive spray cans, this is the best advice I can give you:

Wet sand the body until there is no more gloss. (look up sand paper grit guides online for each step) New paint doesn't stick to glossy surfaces as much as it would to dull surfaces. Wash your car. Get as much dust off as possible (even on areas not being painted). Verify all surfaces to be painted is dull. Find a garage and hang sheets of plastic to create a box large enough for your vehicle and you to work in. Make sure it's completely sealed. Get one of those box fans from Walmart and a house air filter that's the same size as the box fan. Go back to the plastic sheet box in the garage and cut a hole just large enough to fix the box fan in. Try to do it a little high and not at the floor. You could possibly use a ladder to help keep the fan mounted. Seal off the fan with tape on the sides so it's not leaking. (airflow direction of fan needs to blow inside the plastic box. Tape the air filter on the box fan and turn it on. You should now have a clean temporary painting booth to paint in. The fan keeps positive airflow into the plastic box and the filter will do as much as possible to keep dust/bugs out. Before you pull your car into the box, use the fine mist setting on a garden hose and wet the air filter, as well as the insides of the plastic of the box. DO NOT WET THE CEILING! You don't want to risk water dripping down onto your freshly painted surface. After the sides are wet, spray a mist of water on the floor. Your box should have very little dust floating around inside, and the humidity will help allow your paint to flow out better since your automotive spray can paint nozzle is nowhere close to a quality spray gun.

Use isopropyl alcohol to wipe down the surface of your vehicle to get rid of any oil. Use latex gloves to avoid touching the prepped paint surface. Install a metal chain to the underside of your vehicle so it drags on the ground. The chain will help ground the vehicle out. Before pulling the vehicle in, spray the booth one more time with water.

To spray: open your hand and look at the distance between your thumb and pinky. About 6 inches. That's how wide you want your spray pattern to be, and also how far away from the painting surface. Make adjustments with distance to find something that works. Then take a sheet of cardboard or metal and hang it on a wall somewhere. Using the spray distance you just determined, spray the cardboard/metal and count how long it takes for the paint to run. Using that knowledge, determine how fast or slow you need to spray before your paint job will start to run.

When spraying, always remain perpendicular to the surface. Don't change your angle unless the angle of the surface changes. If the surface changes, follow that angle. This is especially necessary if youre painting with metallic paint. Metallic paint can look different when sprayed at different angles.

The first coat of paint, you need to spray it lightly. It's just a tack coat. You should still be able to see through it. Once you do that, walk away. Too many people get too anxious to spray the next coat and your paint will start to run.

Follow guidelines on your paint products for how long to wait between coats.

Also, use single stage paint if you're a beginner. Single stage paint has the color and clear coat mixed into each other. This means that you don't need to go back and spray clear coat after. The difference between single stage and dual stage paint? Dual stage will bring out the best shine, but it's more difficult to do. Most standard cars these days are sprayed with single stage paint.

Answer 6

The main problem is that you are not matching the OEM clear coat coefficient of reflection. It was above Dupli-color's Protective Clear Coat Finish. You need to use Spray Max semi-gloss for clear coats.

Color matching technology is well established. There, you can use junky 1k (that is, slow drying) Duplicolor or whatever for the base coat. (If you enjoy waiting around.) But, for the clear coat, you need to be using a high tech product. The chemistry is very complex. My guess it that Spray Max has the patents, so they have the market's best products, but it does not really matter why. Using their 2k products will allow you to match the reflection coefficient, which is what you need to do.

If you want, you can download https://www.spraymax.com/fileadmin/user_upload/Downloads/Produkte/Prospekte/992466-SprayMax-Produktfolder_USA.pdf and go to the clear coat section. It will say you have two options, matte and gloss, but you actually have more. There are probably high gloss, gloss, semi-gloss, semi-matte, and matte clearcoats by Spray Max out there. As I said, the one I think you want is semi-gloss. (Gloss will probably be too reflective.) More specifically, I think you want 680067 semi gloss clear-coat/ (400 ml) 36+/-2 gloss units at 60° measuring angle. You don't need to sand or have multiple layers.

Different waxes will help you vary the reflection coefficient for perfect matching between these 3-5 levels, but it is better to match the clear coat coefficient of reflection so you don't need to use different waxes for each body part.

Having given what I think is the best answer, I'll now turn to what's wrong with the other 10 answers set out before me. After all, it is pretty dumb to be answering a question that was already correctly answered!

Most other answers complain about sanding. As I explain, it will have zero effect if you use enough paint on the last layer. Lack of sanding could make clear coat peel, but that's not your problem.

Incidentally, this is not popular advice, but I don't think you actually need more than a single layer with Sprax Max 2k. It will probably adhere well enough to have a single layer. It is that good of a product. You don't even need to sand off the Dupli-junk clear coat.

Before now, user35183 and SteveRacer had the best answer, saying that Dupli-color is junk. But, neither gave you a specific alternative you can use.

Several answers complain about thickness (number of coats). No, that's not your problem either. It may be good advice for painting, but it will not help you. You just need to make sure that the last layer is thick enough that the droplets combine on the surface.

Bad final top of top coat layer which will result in orange peel you'll need to sand:

Good final top of top coat layer which you won't need to sand and is best:

(The density of paint droplets needs to be enough that they combine.)

If you agree this is the best answer, upvote it. If you don't, please comment and set me strait.

Answer 7

Sandpaper and Rubbing Compound

Once clear coat is applied you need to sand it with low grit wet and dry sand paper and then rub it out with low grit rubbing compound. This is how you will get it to shine.

You will want to get some of this sandpaper in 1000 to 3000 grit levels as well as some rubbing and polishing compound.

Start with 1000 grit sandpaper, you can use this with water to carry away the fine debris. Work your way to a finer and finer grit with the sandpaper. Follow this up with low grit rubbing compound. You can use moist towels and rags wit the rubbing compound to make a hard surface on the rag after repeatedly buffing. If you have a buffing wheel, this will go much faster. You will see the surface of the paint improve over time begin to shine.

Answer 8

A lot of bad advice and misinformation here, as is typical of the internet. You did not need to sand the base coat, and, when applied properly, you don't need to wet sand and buff the clear.

You put the clear on way too dry. You sprayed from too far away, didn't overlap enough, and didn't lay it on anywhere near heavy enough. To spray an entire hood with rattle cans (which I can't imagine doing), I'm thinking you'd probably need 6 or more cans.

Lay on a thick wet coat, overlap about 60%. Follow up with a similar 2nd coat. You want it just shy of heavy enough to run. The clear will flow out smoothly.

Wet sanding and buffing when you're done would make it smooth as glass, which would not match the orange peel on the oem paint.

Answer 9

i am a licensed autobody tech and the problem is duplicolor. it is a garbage product that doesnt work at all. also you dont sand the color before putting on the clearcoat. if its a metallic paint, the metallics will shift with sanding and you will see it afterwards. spray the base, let it dry for about 30 min then apply the clearcoat on top, no sanding in between. no matter how much duplicolor clear you put on it wont gloss up. you can wet sand and polish the clearcoat once it dries but i havent had it work. i tried it 3 different times from 2010 to 2017 for small spot repairs when people bring me the paint, instead of using professional grade products and no success.

Answer 10

JohnP has it right. Although I've been pretty successful laying thinner coats first just to get the top coat to stick nicely, and ending the job with a "coat so heavy it's just about to run". It seems counter-intuitive, but in my opinion, it's the bast way to get a decent (shiny) result without the proper materials and workspace. Also, avoid doing this outside, because dust and bugs tend to land on wet paint; that's just what they do :)

Answer 11

There's all sorts of misinformation here. Go to YouTube and watch videos on this. Google around. Almost everyone agrees that you absolutely should not make your base coat "perfectly smooth". Most professionals recommend 600 or 800 grit sand before clear coat if they recommend it at all (it's more important if you need correct defects in the base coat). Using a grit above 800 (1000 max) reduces the amount of mechanical adhesion the clear has to stick to the base.

Clear coat will not be high gloss until you wet sand and then polish it. In general, start with 1500, then 2000 up to 2500 (some recommend up to 5000). Then use a random orbital buffer and polishing compound on it and you'll have a glossy finish.

The color comes from the base coat. The glossiness from highly polished clear coat.