Have you ever painted a car before? You can spray over glass smooth primer and still get orange peel. Orange peel is a result of the solvents in the paint drying too quickly, period. Has little to nothing to do with the flatness of a panel; steel dose'nt have orange peel in it, it has waves so the OP isnt coming from the body. Primer is sanding down flat by using guide-coat and still, primer dose'nt get OP, it's too thin.

What?? urethane is as think or thin as you spray it, one coat thin, 5 coats med to thick. The whole purpose of spraying extra coats because you know you will wet sand 2-3 coats off and buff of 1/2 coat. Also, if you used a slow reducer and a slow - med hardener, your paint would not dry so fast.

 

Also wrong, if your environment is not controlled then you will have orange peel; the reason for sanding down the base prior to clearing is to knock down as much orange peel as possible to lesson the sanding of the topcoat or clear where you will see the scratches. You will not see any scratch's in the base unless you are sanding with rocks (400 grit), you do not sand the base with 4 or 600 grit between the coats, you use 800 to 1000; PPG, Glasurite, and RM print it right on the damn can. The reason for this is so that less sanding needs to be done to the clear coat (which fill in the minute 800-1000grit sanding scratch's in the base coat) While it may not be necessary in most paint jobs, there is absolutely nothing wrong with the practice.

Again, the coats are as thick or as thin as you spray them, read the can. If 800 grit is not going to smooth it out, how do you expect that 2000 grit does? One coat of clear is the same thickness as one coat of color; you know why? because clear is colorless base. Clear coat is paint with no pigments in it to add color, acrylics for the gloss and a hardener or activator that is added separately. Not trying to flame you but how many cars and how long have you painted?

 

Primer doesnt get orange peel it is too thin?
what is that lol primer is thick. Y2k high build primer will cover a 180 scratch. that is not thin and it is the least reduced out of any of base or clear. 3 coats of high build and i can guarentee that you will have orange peel.

clear is not base with no pigments in it.( Binder is base with no pigments in it.) If that was true then why do you not add a catalyst to the the base like you do the clear? dry times? it is a whole different chemical makeup than base. FYI I work in a paint shop and we paint 10-12 cars a day on a normal day. never have I seen anyone sand the base and we are using dupont paint.

I use ppg at the house. never sand the base then clear. I am not disagreeing that you shouldnt sand any imperfections out of the base and then rebase the car and then clear it im saying at the end of the day your still going to be spraying an unsanded coat of base over the top and not sanding it before clearing it if its a metallic paint or pearl or a threestage.

Im sure that you can sand a solid base and be fine without recoating but not metallic. If your taking all this time to wetsand the base and remasking everytime you get the car wet then your probably going to take the time to wetsand the clear and buff the entire job flat right.

nextime you paint a metal panel check it with a mill guage after you have primed it, then base the panel to the point you are happy with and check it again with a mil guage then clear the panel with two coats of clear and check again with a mil guage. I can bet that your two coats of clear are alot thicker than your 3-4 coats of base. half of the base you mix up is going to be a reducer and evaporate if your mixing the minimum 1-1 recomendation. I am not trying to flame you either sorry for the long posts. by the way as i stated far above im talking about eurethane paints (ex. PPG dbc line) btw have you used ppg 2060 matte clear? Im looking for info on the spraying characteristics

 

Wasn't talking about a hi build primer, I usually used PPG DZ3 though; reg primer is like gray water.

The catalyst and hardener were for the top coat, and yes clear is a bit different that base, base has no glossing agents in it but essentially thats it w/o getting to technical.

Well yes, I said that. The only purpose sanding the base serves is to knock down bad op or to get rid of trash or to fix a mess up. Most of the time, I'd say it isnt done; just that it can be.

No, I never said sand the base without re coating, you absolutely have to re coat, at least 2 coats.

I never got that serious to measure the metal. I use to try and follow the 1-1 rec but found that it was just a get you close to spraying rec.
I either got strings coming out of the gun or not enough material coming out of the gun. I usually just got close then used test panels; most of the time it was closer to 1-1.10-1.20 (paint to reducer) but depended upon the weather and humidity; had to watch it though, at those amounts sometimes it would flash over too quick. Never used matte clear, never could find a real reason or person who wanted it. I believe that it may be in use on some ford mustangs with the matte finish hood and the new Challenger but I haven't looked at either very closely to see it it is actually paint or vinyl.

 

The thing that causes orange peel in WHATEVER your spraying, the paint starts to set up BEFORE it hits the surface, you have dry and wet paint hitting the surface causing peaks and valleys. Adjusting reducer and airflow can greatly reduce this. Many manufacturers have TONS of peel in their paint because they spray so dry-Fords in particular but a lot of GM's have it too.

To ge a smooth surface, the paint has to be thinned enough to flow when it hits the surface (but not so wet it runs easily). This is a delicate balance and can change with temp/humidity/reducer/hardener.

You ALWAYS need to shoot test paint BEFORE you shoot a panel to get the pattern/flow you desire. Wonder how many people read the data sheet on the paint they shoot???

 

None

 

I do.

 

WOW!! My head hurts

 

mine too lol

 

Thanks for all the comments

Maybe I should have taken the panels to the local paint shop

 

lol yeah didnt mean to steal that or nething.. that got out of hand

 

Not at all it's been an interesting discussion

I'm not sure I dare post up the pics of my panels now though