Remove or apply new paint directly on old paint

[DMM]

Hi,

 

I painted my 1/350 battleship hull in gloss red, and after looking at it, I don't really like how it looks, I want to wipe the red off and use the dull red spray instead, can I use 91% isopropyl alcohol to wipe it off? Will it melt/damage the plastic if I soak it in 91%? OR can I spray the dull red directly onto the old paint?

[Canute]

I'd just respray with dull red paint.

[CPDDET]

I would rough the old surface, prime and repaint. But I'm no expert in the field.

[Toolmaker]

Is it the red or the gloss that you don’t like?

 

If it’s the gloss then try spraying on a dull coat (clear matt varnish). 

[Roger Pellett]

I agree with CPDDET’s post above.  Rub the old finish down with FINE wet/dry sandpaper.  Try 400 grit.  Once the glossy finish Is dull,  wipe down with a soft cloth and repaint. Chemicals  are unnecessary and you don’t know how they’ll react with either the old paint or the plastic hull material.

 

Roger

[DMM]

Thanks everyone! 🙂

[LEGION 12]

On 9/3/2023 at 9:35 AM, Toolmaker said:

Is it the red or the gloss that you don’t like?

 

If it’s the gloss then try spraying on a dull coat (clear matt varnish). 

This is what I do if I have gloss paint on hand , just a coat of dull get's rid of the gloss . 

[Jack-in-the-Blue]

On 9/2/2023 at 5:24 PM, DMM said:

can I use 91% isopropyl alcohol to wipe it off? Will it melt/damage the plastic if I soak it in 91%?

Yes you can. Isopropyl alcohol won’t damage polystyrene but will dissolve acrylic paint. (I am assuming you have used acrylic paint because of your suggested solvent.) 
 

Personally I would remove the paint that you don’t like and start again with primer and topcoat. Painting over the gloss is risky because gloss paint isn’t a very good base layer. Sanding it might lead to unwanted scratches and texture showing through.