Multicoats painting: best way?

[e9999]

still trying to learn a bit about painting.

One general question:

if you're going to put many layers of paint on something:

in general, are you better off doing one at a time, letting fully dry, and I imagine sanding for better adhesion before the next coat, then coating again

or

putting one down, waiting only a bit so it's still "wet" and "sticky" and going with another one of the same stuff right on top of that so that they stick well together and so on...?


in other words, if the previous coat is not fully dry or cured yet, does the next coat stick OK?

 

[thecrazygreek]

I always go with what the paint recomends.

If it's an auto grade paint its usually around 20 minutes between coats. And this will vary based upon what speed hardener you are using etc. There are so many variables it's hard to say.

But I usually let the paint set up (not dry) then shoot again. Letting the paint fully cure between coats is usually not recomended.

 

[73fj55]

Great question. I too am looking for the magical time to re-shoot. I usually do a test area and when I can put my finger on the test area and it is tacky I will shoot again. Usually 30-40. This also depends on humidity and warmth.

That being said. I rattle can sprayed some auto primer on my hood. Waited, for what I thought was long enough. Sprayed again and cracks started to form. It looks like the bottom layer dried and pulled the top layer away from one another....

 

[Wile E Coyote]

I generally don't want the preceeding coat to fully dry. Spraying while tacky or once the coat has flashed, gives the best tie-in between coats.
One time the above does not apply is with the lately popular $50 Rustoleum rolled-on paint jobs.

 

[webelk6]

You should be able to recoat when the 1st coat is tacky. Shouldn't have to do 4 coats unless you want to. If you want to wet sand, fine, in between dry coats only. Shoot it again, and clear coat if applicable. Typically that is buffed.

 

[e9999]

do you get a better finish if you sand in between dry coats than if you recoat wet?

I would think that the only thing that matters is the smoothness of the last coat, right? so OK just to sand that one?


And along those lines, do you even need to sand/buff the last paint coat before the clear coat or do you just shoot the clear coat over the raw color coat and only buff the former?


(yes, I know that I don't know anything about this, so sorry about the lame questions)

 

[webelk6]

do you get a better finish if you sand in between dry coats than if you recoat wet?

I would think that the only thing that matters is the smoothness of the last coat, right? so OK just to sand that one?


And along those lines, do you even need to sand/buff the last paint coat before the clear coat or do you just shoot the clear coat over the raw color coat and only buff the former?


(yes, I know that I don't know anything about this, so sorry about the lame questions)

1. coat tacky for best results, and to avoid runs.

2.You can get a smoother finish if wet sanding in between coats.(coats should be dry then) I find that recoating tacky is best. Let dry, then wet sand . If you want , shoot it again, just for good measure. You could prolly paint a whole cruiser with 1/2-3/4 of a gallon, so it's not like you are piling the paint on.

3.Wet sanding is for smoothness, and to get out dust particles. Use a cleaner post wet sanding(can't think of the name right now).

4.When last coat(2nd) is done, wet sand, clean, then clear coat. Clear coat is typically buffed. Some guys "poor, pile" it on. Because they are excellent buffers
Hope that helps.
best
Scott