Metallic base coat

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PostPosted: Thu Jan 03, 2019 2:28 am
Hi folks,

Newb question here. I just shot a metallic silver base coat (ready to shoot)... should it be totally even in appearance all over? I have a fairly big section which is cloudy and then a couple of other spots that kinda look like i tested my gun on it (which i didnt).

Been reading up on the cloudy appearance thing and saw that moisture can cause this. I also read that if you change gun angle or distance during painting you can risk that the metallic flakes stand on their ends... (or something like that). It feels different to the touch than the other side.

Any ideas?

Cheers,

Mike

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PostPosted: Thu Jan 03, 2019 4:49 am
In Brazil it would be mid-summer, just as here in Australia.

The heat means that your base coat will dry much faster so even small variations in your spray technique like pulling the gun back a bit, could result in areas where the paint will have a dry finish because some or all of the thinner has already evaporated on the way to the panel. A slower thinner will help to keep a consistent wet application.

If you're in a humid area the humidity can, as you suggested, become entrapped in the atomised particles of paint coming out of the gun, resulting in a cloudy or milky look. Often the simple application of some heat, by a heat gun or even hair dryer can evaporate the water and restore the look. If exceptionally bad some time in sunshine may help, or you may have to rub back and respray.

Silver can be difficult. Try the heat trick on the cloudy areas. For the dry spots, very gently rub back with P1500 to get the surface smooth and then respray your base, being careful to ensure that the application is consistent. Don't spray base or any acrylic based paint (most solvent base coats are modified acrylic) when it is overly humid or raining.
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PostPosted: Thu Jan 03, 2019 3:05 pm
It should all look the same.

Silver is tough color to shoot

Air pressure to the gun needs to be consistent water and oil free air, No tilting or flaring of gun while spraying keep gun perpendicular to substrate and gun distance's from substrate robot consistent with a 50% overlap. Being robot consistent is the trick to spraying any metallic.

a Drop coat can also help with some inconsistency.

Also Use the correct temp Reducer for when spraying.
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PostPosted: Thu Jan 03, 2019 4:25 pm
Spraying silvers to wet or to dry are the biggest reasons
for uneven silvers.
JC.

(It's not custom painting-it's custom sanding)



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PostPosted: Thu Jan 03, 2019 4:57 pm
:goodpost: JC
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PostPosted: Thu Jan 03, 2019 8:45 pm
NFT5 wrote:In Brazil it would be mid-summer, just as here in Australia.

The heat means that your base coat will dry much faster so even small variations in your spray technique like pulling the gun back a bit, could result in areas where the paint will have a dry finish because some or all of the thinner has already evaporated on the way to the panel. A slower thinner will help to keep a consistent wet application.

If you're in a humid area the humidity can, as you suggested, become entrapped in the atomised particles of paint coming out of the gun, resulting in a cloudy or milky look. Often the simple application of some heat, by a heat gun or even hair dryer can evaporate the water and restore the look. If exceptionally bad some time in sunshine may help, or you may have to rub back and respray.

Silver can be difficult. Try the heat trick on the cloudy areas. For the dry spots, very gently rub back with P1500 to get the surface smooth and then respray your base, being careful to ensure that the application is consistent. Don't spray base or any acrylic based paint (most solvent base coats are modified acrylic) when it is overly humid or raining.



Thanks heaps NFT5.

I did as you suggested. Just finished painting and i'm happy with the result. It was down to technique in the end, knowing what to expect (basically wysiwyg). I had been spraying a bit too wet. Watching guys on youtube helped a lot - I should have done that to begin with.

Thanks again.

Cheers,

Mike



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PostPosted: Thu Jan 03, 2019 8:46 pm
Doright wrote:It should all look the same.

Silver is tough color to shoot

Air pressure to the gun needs to be consistent water and oil free air, No tilting or flaring of gun while spraying keep gun perpendicular to substrate and gun distance's from substrate robot consistent with a 50% overlap. Being robot consistent is the trick to spraying any metallic.

a Drop coat can also help with some inconsistency.

Also Use the correct temp Reducer for when spraying.


Thanks Doright!!



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PostPosted: Thu Jan 03, 2019 8:49 pm
JCCLARK wrote:Spraying silvers to wet or to dry are the biggest reasons
for uneven silvers.


Yeah you nailed it, i backed off the fluid and added a little more distance and bingo... consistency!

Thanks,

Mike

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PostPosted: Fri Jan 04, 2019 1:09 pm
i will add silver goes best over dark sealer. dark gray is best
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PostPosted: Sat Jan 05, 2019 4:44 pm
Good tip painterDave!

Thanks!

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