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Spots on gold spray paint


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Anyone know why I'm getting these reactions with gold cars? Doesn't matter what brand paint. This is Tamiya rattle can but its happened with Rustoleum too. The only thing in common is Mr Hobby clear. I think the gold may be tarnishing.. I would spray color, let it dry. Wash with dawn and clearcoat, wet sand and more clear. It looked perfect for a day or two at the end and these came up 

 

Kinda bummers but I'm not gonna redo it

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Edited by Hondamatic
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To me it looks like the spray nozzle might be partially blocked causing small droplets to form and be propelled onto the model's surface. The other possibility may have to do with your humidity levels. Hawaii is a beautiful place but is also known for high humidity.  

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Posted (edited)

These are some pictures from a few days before, with the first coat of clear. It looked really good and the spots came out afterwards. Also using a food dehydrator 

I only think its tarnishing because back when I was a kid my gold cars would tarnish because I didn't use clear

Wondering if I should clear the car without washing it beforehand. I always wash and use hair dryer to remove dust, etc. If there's a better way I'd love to try. This is why I rarely 2 tone cars too

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Edited by Hondamatic
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1 hour ago, espo said:

To me it looks like the spray nozzle might be partially blocked causing small droplets to form and be propelled onto the model's surface. The other possibility may have to do with your humidity levels. Hawaii is a beautiful place but is also known for high humidity.  

Maybe he could go "up-country" to paint.

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Try spraying your clear as soon as the last coat of paint flashes. I've sprayed two coats of paint one day. Then sprayed a coat of paint and a coat of clear the next day. Whichever paint you use, make sure your clear is the same brand. 

The spots on your paint looks like the clear has spit out. Droplets can can effect the paint because they're thick at the moment they hit the paint which can make that spot wet again. 

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16 minutes ago, 1972coronet said:

Never wet/colour sand metallics (or pearls); only the clear coat(s). Even if the gold/silver/copper/brass is 'solid' (no obvious metallic), they're de facto metallic. 

Disagree.  What are you gonna do with a lump of dirt or cat hair or something in your color coat?  Just clear over it?  How are you going to fix that with polishing?

Here's a video from a much better painter than me demonstrating how to fix boo-boos in metallic and pearl paintjobs:

 

To answer OP's question, I would try a different clear and see what happens...that would at least pin down what's doing it...

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23 minutes ago, 1972coronet said:

Never wet/colour sand metallics (or pearls); only the clear coat(s). Even if the gold/silver/copper/brass is 'solid' (no obvious metallic), they're de facto metallic. 

Yes, I know this too well. Thats why I'll lay a coat of clear before sanding 

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1 hour ago, CabDriver said:

Disagree.  What are you gonna do with a lump of dirt or cat hair or something in your color coat?  Just clear over it?  How are you going to fix that with polishing?

Here's a video from a much better painter than me demonstrating how to fix boo-boos in metallic and pearl paintjobs

Thanks for that tutorial. I should've specified that the final coat shouldn't be wet/colour sanded of metallics/ pearls. I wasn't speaking to fixing goofs, removing contaminants, etc.

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You should apply your method too a spoon without using the dawn and see if the same thing happens.  If same thing happens try a different clear doing same method on a different spoon. 

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4 minutes ago, Sandboarder said:

I also think it because of the washing. Either step this step or shoot the clear coat closer to the last colour coat. 

I do it to remove dust, etc. I would love to minimize washing bodies but I'd like to learn what other guys do. Gotta use the search function sometime 

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13 minutes ago, Hondamatic said:

I do it to remove dust, etc. I would love to minimize washing bodies but I'd like to learn what other guys do. Gotta use the search function sometime 

You don't need to use dawn to remove dust when washing the body

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1 hour ago, Hondamatic said:

I do it to remove dust, etc. I would love to minimize washing bodies but I'd like to learn what other guys do. Gotta use the search function sometime 


I normally just blow air to remove dust (airbrush or from mouth) 

 

I only wash after sanding or polishing if I need to remove particles. 
 

You could spray your clear coat 30 minutes after your last colour coat depending on paint thickness and it it’s the same paint that’s flashed off (normally won’t taken more then a few minutes) That would reduce the time/chance that dust has to settle on your model. 

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If my base color coat gets a hair or lump of dirt I scuff that, then shoot a final base coat,just a single coat to even things up. Once dry I go right to the clear, no washing. I just blow it off with the airbrush ( air only) then shoot the clear.

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Thanks for all the replies, guys. When I used to build 15 years ago I would let the color flash and put down clear, and I just got back into the hobby last year and read some stories that if I didn't let the base dry enough, the clear could crack over time ( I'm guessing due to different drying rates, and I do have some older cars that did this) so I've been being a little cautious. But now I'll have to take a better look into my methods, and I'll post if I figure out what happened to the gold paint

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On 3/23/2022 at 4:28 PM, 1972coronet said:

Thanks for that tutorial. I should've specified that the final coat shouldn't be wet/colour sanded of metallics/ pearls. I wasn't speaking to fixing goofs, removing contaminants, etc.

I completely understood what you meant. That video keeps getting shared on here but I'm not really understanding the controversy. You can't actually sand metallic/pearl coats and bring back the depth with clear coat. You have to respray the last coat as you sprayed and live with that result before clear coating. You can sand your clear coat and respray that.

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You can wet sand metallics and pearls. I've done it with hok on a deep chip (dropped my sprue cutters on the roof) and it turned out fine. The secret is not to change direction and not to press too hard on it. You can see how it was done here       http://www.modelcarsmag.com/forums/topic/159305-57-bug-with-working-suspension-teardrop-trailer/

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Don't wet your color coat between color and clear. First, try a blast of air to remove any dust, then wipe with a Tack Rag, or Tack Cloth. Don't use the very tacky ( yellow) ones from the home center, those are for the heavier dust of wood workers. Instead, find an auto-body/paint supplier and get the light blue tack cloths. These have a lower tack, but will absolutely pull away any stray dust particles. Don't rub hard, simply lightly move it over the entire surface with the least amount of pressure you can. If you're not familiar, a "tack rag", as they're often called, is cotton cheese cloth impregnated with a somewhat sticky resin that grabs and holds dust like nothing else, while being chemically inert as far as paint coats are concerned.

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