Primer color under white paint.

[neil_w]

My paint regimen is Rustoleum, 2x for most stuff and Stops Rust Metallics when needed.

I have always used one of two possible primers (or both): grey primer/filler, mainly for the "filler" part, and white 2x primer. My use of the white primer is irregular; sometimes I'll go top coat right on top of the filler/primer, and usually that works out OK.

Recently while stocking up, I bought a can of grey 2x primer. I thought that I should use it on white base coats, because then I'd be able to see what the heck I was doing. When I had white paint on top of white primer, I couldn't tell where I had coverage. Then I thought oh no, white paint on grey primer will be dull. And *then* I thought, this should be no worse then when I've painted right on the filler/primer, and that has always worked out fine.

I know there are some paint colors (red, yellow) that are less opaque and really call for white primer or undercoat to achieve maximum color intensity. But for white paint, what is the generally recommended procedure? I'm probably going to try the grey primer either way, but curious if this is officially considered a no-no.

 

[mikec]

I've never had a problem with white over gray primer. I use white primer only for red/yellow/orange color coats or fluorescents. BTW, I've given up on Rusto 2x gloss white because I've had too many cottage cheese experiences; semi-gloss seems OK. I like Rusto appliance epoxy for fiberglass rockets.

 

[Bill S]

I use white Tamiya lacquer spray over grey primer. It seems to need more coats (4-5?) than if I were using a darker color over grey. But I can't complain. Just do lots of thin coats, with a slightly heavier last coat to make the surface nice and glossy.

 

[lakeroadster]

Neil, I used Rustoleum sandable gray primer (& sanded it) under the white on my F-79. Worked well for me.

 

[dr wogz]

if you look a teh modeling world (plastics not babes) a dark undercoat usually give a heavier 'feel' the final paint job. So, I would assume white on white will give you a pure light white; snow white. But white on a grey base will give you a heavy sort of white, something with substance / weight / heft..

 

[neil_w]

But white on a grey base will give you a heavy sort of white, something with substance / weight / heft..

That makes it sound intentional and desirable.

 

[David Schwantz]

neil, you may be having a lighting issue if you cannot see the paint going down. when you put white over white primer. if you can, set up better lighting, you don't want any shadows in your paint area.

 

[neil_w]

neil, you may be having a lighting issue if you cannot see the paint going down. when you put white over white primer. if you can, set up better lighting, you don't want any shadows in your paint area.

I paint outside during the daytime in front of my shed.

 

[kuririn]

The white primer I use is runnier than grey filler/primer.
So I use two light coats, drying in between
I use it under light colors: white, tan, yellow, orange, red and fluorescents.
For medium colors, it's grey filler/primer: green, blue, grey, medium brown
For dark colors, dark grey or black primer: Navy blue, purple, maroon, dark green, dark grey, dark brown, black.
Black primer for metallics.
Coverage for gloss white on white primer shouldn't be a problem.
Just look for the sheen.
Flat white on white primer is more problematic.

 

[modeltrains]

I'm probably going to try the grey primer either way, but curious if this is officially considered a no-no.

Haven't ever been any officials come to my house and tell me that.
Been using DupliColor grey filler-primer for a long time on rockets and other models which were getting painted white.
As you have said it is helpful to better see where the white paint coat is going and how well it is covering.

 

[dhbarr]

I alternate a brown and a grey primer so I can better see where I haven't got coverage. My paint jobs probably shouldn't be used as how-to examples ^_^

 

[Antares JS]

IMO putting white paint over white primer is unnecessary. I've found that if your final intended color is white, just using the white primer for your color coat works out pretty well, and you can just add clearcoat on top of your primer to seal your decals and get your gloss/matte finish. Primer is also more opaque and better at covering up a color underneath it if you need to put gray filler primer under your white.

 

[Mugs914]

IMO putting white paint over white primer is unnecessary. I've found that if your final intended color is white, just using the white primer for your color coat works out pretty well, and you can just add clearcoat on top of your primer to seal your decals and get your gloss/matte finish. Primer is also more opaque and better at covering up a color underneath it if you need to put gray filler primer under your white.

I just read through this thread and was going to post the same thing! This is exactly what I do for white finishes.

I use 2X white primer, sand everything smooth, add secondary colors, decals and clear coats. If I have a bunch of surface detail that I don't want to cover up, I'll use Tamiya white primer. It is much "finer" and doesn't clog the small details.

 

[neil_w]

I must say, the idea of using primer as topcoat is something I had never heard of or considered. And despite reports of success with it, I'd be reluctant to try it.

That said, I must admit the 2x white primer is incredibly easy to lay down, although I'm not convinced its coverage is any better than the 2x white. I've switched to the Semi-gloss in the hope of reducing the likelihood of cottage-cheesing.

 

[Mugs914]

You might want to give it a try sometime. It lays down very nicely, as you said, it is absolutely opaque, and any problems can easily be sanded out. I bet it is lighter than gloss paint too, if you worry about weight to that degree.

It works well for me, though I must admit that I do kinda feel like its cheating a little bit!

The white on all of these is the primer coat...

Gloss coat. I used Future floor polish on this one...


Testors matte coat...


Don't remember what the topcoat was on this one, but it is a semi-gloss.

 

[jqavins]

My paint regimen is Rustoleum, 2x for most stuff and Stops Rust Metallics when needed.

I have always used one of two possible primers (or both): grey primer/filler, mainly for the "filler" part, and white 2x primer. My use of the white primer is irregular; sometimes I'll go top coat right on top of the filler/primer, and usually that works out OK.

Recently while stocking up, I bought a can of grey 2x primer. I thought that I should use it on white base coats, because then I'd be able to see what the heck I was doing. When I had white paint on top of white primer, I couldn't tell where I had coverage. Then I thought oh no, white paint on grey primer will be dull. And *then* I thought, this should be no worse then when I've painted right on the filler/primer, and that has always worked out fine.

I know there are some paint colors (red, yellow) that are less opaque and really call for white primer or undercoat to achieve maximum color intensity. But for white paint, what is the generally recommended procedure? I'm probably going to try the grey primer either way, but curious if this is officially considered a no-no.

You and I have had so many similar thoughts on a number of subjects that I've occasionally suspected us of secretly being the same person. The way you're overthinking this, I now have another piece of evidence for that hypothesis.

 

[dpower]

I always use gray primer for a white top-coat, mostly because I've tried a lot of primers, and none of the white ones sand as nice as my favorite gray primers - 3M Bondo, and Dupli-Color. White primers are reserved for times when I need a white undercoat. I used primer as a top-coat just once, to get just the right rust-red color for a Patriot, followed by a clear coat.

 

[Lord Rory Gin]

I just read through this thread and was going to post the same thing! This is exactly what I do for white finishes.

I use 2X white primer, sand everything smooth, add secondary colors, decals and clear coats. If I have a bunch of surface detail that I don't want to cover up, I'll use Tamiya white primer. It is much "finer" and doesn't clog the small details.

I second that. Tamiya primer is the best I've found. In fact Tamiya paints are better than Rustoleum too because of the finer base. Right now I use Rustoleum as a filler coat and it sands really well. Then I apply a 2nd coat and wet sand.

Tamiya is a lighter grey and doesn't hide as much of the model detail work and has less tendency to run but it needs an extra coat or two to finish completely. If it weren't for the fact that they only come in 100 ml cans and cost so much, I would use them exclusively.

All that said, I wouldn't mind trying out an airbrush in the future for anything smaller than 3" dia. rockets. Maybe in the future.