Buffing out roughness in clear coat.

[John Schmidt]

I've had a couple suggestions re. what to use, right now I'm looking for methods others have used. It's a plastic trunk from a GL1100 Wing, painted black over a couple coats of primer which was finally sanded down using 800 by hand. I then sprayed two light coats of clear, no sanding of each coat, and a heavier third coat which I'm letting dry/cure. My problem is....the sides and part of the back where the latches are, seem more rough than the top. The top is smooth and has a nice glossy finish, the sides mentioned...not so much. I'm wondering if I should use some 1000 or 1500 grit and go over the entire surface lightly, then buff it out. What method has worked for you in the past? This is just the top of the trunk, the bottom is now repaired and is next to be painted so I'm looking for a process that will work overall. I'm not a painter, just gullible enough to try anything once and this is proving I had better leave painting to the pros.

So, what methods have been used in your past, including the compound or whatever, and the type of buffer. I have a couple different ones that aren't high RPM, but also have an air driven one. I don't think I should use the air unit, the high speed would burn the finish I think.

[Walküre]

John - not seeing it, it's hard to give a definitive answer, but as a rule, you have to figure out what the roughness is, and how deep it is...

Two different types of "roughness", and different "cures" - there's "orange peel", which is a roughness in the coat itself, and then there's contamination - either actual dust, or overspray from painting.

Is it definitely from the clear coat, or is it possibly from deeper in the color layer? It sounds like it's from the clear, since you say you sanded the black. 800 grit's a good choice. That would eliminate any problems from the color coat.

Did you clear coat fairly soon after finishing the color coat? Sooner is better, as it allows the clear to bond chemically with the color coat, as well as decrease the possibility of dry overspray.

Did you possibly spray "dry"? That is, when the clear dries almost before going on the lid. That can cause a roughness, really easily. Painting in the wind, or a really warm shop, can do that. The clear should look like glass, when you spray it on. A problem a lot of people do, is go back over it "one more time", and since they are going both faster, and trying to put on less coat, it tends to go on dry, causing roughness. That you mentioned that the top is fine, but sides are rough, it leads me to believe that it went on "dry" on the sides, either with overspray, or going faster.

Did you use a tack cloth, before the clear coats? that's a MUST, even if it "LOOKS" fine, it usually isn't.

Depending on how rough it is, the 1500 grit before buffing, should GREATLY improve it. Just be sure you don't go through into the color coat, as then you might be re-doing it all.

Again, I'm not a professional painter, but I DID spend the night in a Holiday Express...

Let us know how it turns out - you are correct, use a slow speed buffer. And you definitely want to get your technique ironed out, before you go to the next piece - it's a LOT easier to do the lid two or three times, than the entire trunk!

You'll get it - suddenly it will just "click" and you'll amaze yourself!!

The big thing is, have fun.

On another note, you might take it to a pro, and just ask them - most pro's I have ever known, have been more than happy to give hints and tips to someone - they seem to KNOW that if you don't get it right, that you'll be back to pay them to do it. They'll also be able to tell you exactly what you have.

Keep us posted, please! We all like to learn from other's efforts.

 

EDIT - on a side note, I'm getting ready to paint my saddlebags - my "pro" quoted me $200, for a custom design, and two-color, with pinstripe, to match my tank. It would be hard for me to buy all the paints and other chemicals, to do it, for that! It will probably be one of the very first times, I haven't done my own painting, but I KNOW his will be perfect, the first time. He has done all my insurance work, in the past, and has always done EXCELLENT work.

My bags are going to look similar to this one, but the white will be black, and really lends itself to the tank lines...

[John Schmidt]

The surface was smooth after the 800 sanding, and after wiping with a soft cloth I then used a tack cloth. I sprayed in the garage, there was no air movement and I had misted down the floor to help keep the dust down. Only thing I can figure is either "cold" spray or overspray. It's glossy even on the rough surface, rough is actually an overstatement. It's just not as smooth as the top. I'll see how it turns out from buffing, if still not satisfactory I'll reshoot the entire thing.

I need some ideas on what to use for buffing compound, one suggestion was 3m Swirl Mark Remover, followed with 3m Finishing Wax.

[Walküre]

Sounds definitely like orange peel - usually has to do with the actual mix of the paint, or the technique to a little lesser extent. Most often because the clear didn't "flow out", and "probably" because the clear coat wasn't thick enough on the sides. Often, clear coat doesn't get reduced, so it adheres pretty good, but human nature is to not spray quite as much on vertical surfaces, as horizontal surfaces. But you need a lot of product, to flow out. But know that almost ALL vehicles have orange peel. And more so now than 50 years ago - due to newer solvents that don't allow the flow that years past yielded. Go to a new Cadillac car lot, and look at the orange peel there.

I think you'll find that the sanding/buffing will give a very satisfactory job. If not, more clear coats are called for. Practice makes perfect!   

Ooow, ooow...just found this, one of the best descriptions/resolve I've ever seen...

ORANGE PEEL

(Poor Flow, Texture)

Paint film having an uneven texture that resembles the skin of an orange.
CAUSE

   1. Under reduction and/or air pressure too low.
   2. Thinner/reducer evaporates too fast for spray conditions.
   3. Excessive film thickness or piling on of heavy wet coats.
   4. Improper spray gun set-up.
   5. Improper painting technique.

REPAIR

   1. Compound or polish to reduce surface texture.
   2. Or, sand smooth with 1200 or finer grit sandpaper, compound and polish to restore gloss.
   3. Or, sand smooth and refinish.

PREVENTION

   1. Use proper reduction ratio and spray at recommended air pressure.
   2. Select recommended thinner/reducer based on temperature, humidity, air movement, and size of repair.
   3. Avoid heavy coats and excessive film thickness.
   4. Use recommended spray gun, fluid tip and air cap for the material being sprayed. Always adjust the gun for best atomization and balanced spray pattern before paint application.
   5. During paint application, hold the gun perpendicular and parallel to the surface. Adjust speed of pass, pattern overlap, and distance from the panel to achieve the desired appearance.

   

R

[John Schmidt]

This was the 6th try at getting a decent coat, all to no avail. I sanded a bit by hand on the rough portion using 1200 and it went through the base coat to the primer in short order. I tried it elsewhere on the lid, same result. That means starting over on the entire thing, something I wasn't inclined to do again. I have a long standing approach to things that irritate me when trying to do something.  I'll try numerous times, often dozens of trials but this time it was only six.  If, after numerous tries I can't get close to the result I'm looking for and it's irritating beyond measure, I simply get rid of the source of irritation and don't look back. Today was no exception....the trunk is in the trash. My investment is small so it's not a big deal, and I'm OK with it.

At this point, I'll look around and find something already painted if I decide to continue with the project. Until then....thanks for the input and advice. Painting is something I'll never attempt again, just thought I'd give it a try this once. Lesson learned, moving on. 

[mikeb]

i have a 20 year long standing agreement with the fellow that dose my paint work ..
i dont paint  and he dont wire anything 
we have both tried to do each others jobs it just dont work out.
 .. stick with what your good with..
  its works for me !!!!!!

[John Schmidt]

You're right on that. I can do just about anything else on the bike, cars, etc., but painting I found out just isn't my bag. Especially if there's nobody to supervise until you learn the tricks of the trade. At my age, I'm not even going to try that approach. But, I had to try it at least once....and that was enough.

[wizard -vrccds#125]

When you sand MAKE SURE YOU WET SAND ! or you will go thru to primer in no time with light presure. Don't ask how I know 

[Robert]

Wizard has it right you will never get the correct finish with base then clear without wet sanding with say 2000 grit. Spray the clear and build up a pretty thick coat. Not to thick though otherwise it will crack but enough to give you some sanding room. After you sand buff it with a good polishing compound the 3m is usually pretty good and you can even use a glaze if you want then wax and your done. When you spray make sure there is no silicon around it will screw up the paint faster than dust. If you spray correctly you will be able to tell when you sand because there will be no unevenness in the haze from the sand paper. Dust really wont be a problem as long as you have enough clear.