Painting Problems

[ThePhantomBan...]

I have a K8 Bandit 650 that I bought recently. I've been experimenting with repainting a few areas, most recently I have been repainting the plastic cover over the clutch release actuator next to the gear selector lever. I sanded, keyed, primed with a good quality plastic primer then painted Matt black. All looked good yesterday then this morning I noticed defects in the finish and I can figure out what I did wrong. Anyone who would take the time to look at the photo and provide insight i would be very grateful.

https://photos.app.goo.gl/Cnmm8rVkQTttcmsX9 [/img]

[Riejufixing]

I would guess "surface contamination". How did you clean the plastic (and do you know what sort of plastic it is, and what primer did you put on it)? A pro paint sprayer will be along to tell you what's happened in a minute.

[jeffyjeff]

If you are painting plastic, you need to use an "adhesion promotor" to make sure the paint bonds with the material you are painting. Here is a link that explains the need: https://coatings.specialchem.com/selection-guide/select-adhesion-promoters-for-coatings. You can google "adhesion promoter" for more information and some youtube links that explain further. Good luck.
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History shows again and again how nature points out the folly of men - BOC

[A100man]

Looks like your primer might have pooled in those corners and was not cured when you sprayed the top coat.
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[ThePhantomBan...]

[ThePhantomBan...]

[ThePhantomBan...]

[jeffyjeff]

[andy_uk]

How many coats of the matt black did you give it?
Plenty of thinner coats are better than fewer heavy coats.
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Aprilia Classic 125, GS500E, ER5-A1, ER5-C4, ER6 & an XJ6 project frame...

[A100man]

[MCN]

Moisture, humidity and or Electrostatic effect.
Items can hold a static charge and a magnetic field like which repels atomized paint or attracts it.
But usually that effect looks like the paint was very thinly applied.
Paint equipment is connected to the target electrostatic to control the effect.

Over thinned paint can cause that too. Where the solvent carrier evaporates and leaves the clay base which pools causing gaps in the coating.

Anyway... rub it down again. (Properly this time. Remove all the little lumps bumps and fill the dings. New paint looks much better on a flattened surface.)
Repaint using the top coat.
Thin coat.
Tack dry.
Thin coat.
Tack dry.
Thin coat.
Rubbing down with flour grade wet and dry helps to show up any imperfections. The coats can fill smaller dings too.
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[Easy-X]

I was trying to think of a way to create such an effect intentionally and all I can think of is spraying over a wet layer that then shrinks
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Royal Enfield Continental GT 535, Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter