Is this the proper technique to paint matte white onto a GPU shroud?

[AccDossNumber15]

Hopefully this is correct:

• Sand the shroud with a 100 grit.
• Use a flat white primer and wait for an hour to dry.
• Use a flat (matte) white spray paint and wait 24 hours then sand with 1500 grit.
• Repeat the step above 2 more times then finally sand with 3000 grit for a matte look.
  • Does using 5000, 7000, etc. grit make a difference in-terms of feel and appearance?

Is that correct?

[Needfuldoer]

100 grit is way too aggressive for scuffing plastic. All you need to do is dull the gloss so the paint has something to grab onto. I'd start with 400 or 800 grit.

 

You also shouldn't have to block sand with 1500 grit or higher unless you're working up to a polished surface. Just paint several light coats with a matte white spray paint.

[AccDossNumber15]

6 minutes ago, Needfuldoer said:

100 grit is way too aggressive for scuffing plastic. All you need to do is dull the gloss so the paint has something to grab onto. I'd start with 400 or 800 grit.

 

You also shouldn't have to block sand with 1500 grit or higher unless you're working up to a polished surface. Just paint several light coats with a matte white spray paint.

I'm a bit confused about you second paragraph. Are you saying I can sand it by hand (aka without a sand block) or are you saying I shouldn't sand between each light coats? Just to clarify I'm using sandpaper. JayzTwoCents said to sand it with per coat to smooth out any dust that attached itself.
 

[Needfuldoer]

9 minutes ago, AccDossNumber15 said:

I'm a bit confused about you second paragraph. Are you saying I can sand it by hand (aka without a sand block) or are you saying I shouldn't sand between each light coats? Just to clarify I'm using sandpaper. JayzTwoCents said to sand it with per coat to smooth out any dust that attached itself.
 

You don't need to sand between light coats. If you're putting them on light enough, it's going to take two or three coats to completely cover anyway.

 

Sanding with 2000, 2500, 3000, etc paper is what auto body shops do before they cut and compound then polish to restore gloss. If you're after a matte finish, you shouldn't need to do those steps at all.

 

Don't paint in the open outdoors, use something like a big cardboard box as a 'booth'. (You can get a one for a few dollars at any hardware store.) That should minimize the amount of dust that gets onto the wet paint.

[Poinkachu]

Agree with what @Needfuldoer said, 100 grit is crazy, especially if you plan to use it on plastic.

So far for all my DIYs I didn't even need to use 220 grit, and that includes a DIY steel top exhaust cover for my pc case that were made from salvaged old pc case.

[AccDossNumber15]

3 hours ago, Poinkachu said:

Agree with what @Needfuldoer said, 100 grit is crazy, especially if you plan to use it on plastic.

So far for all my DIYs I didn't even need to use 220 grit, and that includes a DIY steel top exhaust cover for my pc case that were made from salvaged old pc case.

Regarding metal (and plastic), does acrylic based spray paint work well? I found the sprays I needed but I'm not sure if this is too much:

• Primer white matte (primer)
• Flurescent flat white (coat)
• Flat clear matte (clear finish)

[Poinkachu]

1 hour ago, AccDossNumber15 said:

Regarding metal (and plastic), does acrylic based spray paint work well? I found the sprays I needed but I'm not sure if this is too much:

• Primer white matte (primer)
• Flurescent flat white (coat)
• Flat clear matte (clear finish)

I'm not the best person to ask about this since :
#1. I'm not that much savvy about it, mainly due to reason #2 and #3

#2. In my country pretty sure every local brand selling the same type.

#3. Only a small amount of local brand actually put the type on the label

It is acrylic, just not sure whether they're lacquer or enamel.

 

Maybe @Needfuldoer have some better info/insight about it.

 

Here's a suggestion for you though if you are new to it :

Do trial runs using a small piece of junk of the same or pretty much same material type as your project.

Take note of each trial run's configuration and see which result is best

This is also to make yourself familiar to spray painting and the spray paint you use.

[AccDossNumber15]

On 5/14/2024 at 7:12 PM, Needfuldoer said:

You don't need to sand between light coats. If you're putting them on light enough, it's going to take two or three coats to completely cover anyway.

 

Sanding with 2000, 2500, 3000, etc paper is what auto body shops do before they cut and compound then polish to restore gloss. If you're after a matte finish, you shouldn't need to do those steps at all.

 

Don't paint in the open outdoors, use something like a big cardboard box as a 'booth'. (You can get a one for a few dollars at any hardware store.) That should minimize the amount of dust that gets onto the wet paint.

Hello, this is a follow up, I tried to apply the primer, but should it be thin where I can see the base color of the metal case, gray in this case? My application is a bit off, with some areas have denser primer, visible streaks, and one area having run off/drips. Should I sand it with 220 grit after 24 hours to flaten the primer?

[Needfuldoer]

Just now, AccDossNumber15 said:

Hello, this is a follow up, I tried to apply the primer, but should it be thin where I can see the base color of the metal case, gray in this case? My application is a bit off, with some areas have denser primer, visible streaks, and one area having run off/drips. Should I sand it with 220 grit after 24 hours to flaten the primer?

Prime and sand the rough parts until the primer fills in all the little divots and brings them up level with the surrounding surface. Then do a full primer coat over the entire piece. Top coat with paint after giving the primer as much time to cure as the instructions on the can tell you to.

[Poinkachu]

3 hours ago, AccDossNumber15 said:

Hello, this is a follow up, I tried to apply the primer, but should it be thin where I can see the base color of the metal case, gray in this case? My application is a bit off, with some areas have denser primer, visible streaks, and one area having run off/drips. Should I sand it with 220 grit after 24 hours to flaten the primer?

Do try to avoid run-offs / drips, it's a sign you applied too much to soon on that particular area

[Poinkachu]

Like I have said btw

When it's about spray painting... it is much more preferable if one practice first.

At least until one is familiar with basic spray painting technique.

[AccDossNumber15]

2 hours ago, Poinkachu said:

Like I have said btw

When it's about spray painting... it is much more preferable if one practice first.

At least until one is familiar with basic spray painting technique.

Yeah, I did as fuld said and there are still a few areas thin with primer like the edges/corners and I haven't been able to remove blend the run off.

[AccDossNumber15]

@NeedfuldoerHere's the final product, I screwed up somewhere but I don't know exactly. Should I hit the thinner areas with a 4th thick coat? Only the first pic seems decent.

[AI_Must_Di3]

What gpu does this shroud go to? You could have just Plastidipped it and saved yourself a ton of work and headaches. Plus its peelable if you want the original look back and it doesnt affect any warranty you may have like painting would.

[AccDossNumber15]

1 hour ago, AI_Must_Di3 said:

What gpu does this shroud go to? You could have just Plastidipped it and saved yourself a ton of work and headaches. Plus its peelable if you want the original look back and it doesnt affect any warranty you may have like painting would.

I used this PSU shourd as a test run. Also, my the GPU itself out of warranty because the previous owner removed two of the memory modules.