Painting small trim item

Painting small trim item

Author
Discussion

inline6bmwfan

Original Poster:

93 posts

29 months

Sunday 21st May 2023
quotequote all
Ive seen so many different guides online and im completely confused on a simple way to spray 2 small external pieces of trim on the outside of my car.

2 pieces are currently grey. Want to spray gloss black, pieces are plastic.

What grit sandpaper? How many times do i use said sandpaper, do i need hi build primer? Do i need lacquer if i use GLOSS black spray paint?

Any simple step by step?

steveo3002

10,659 posts

181 months

Sunday 21st May 2023
quotequote all
grey bare plastic or already painted in grey?

inline6bmwfan

Original Poster:

93 posts

29 months

Sunday 21st May 2023
quotequote all
steveo3002 said:
grey bare plastic or already painted in grey?
Already painted in gray, as it comes from the factory.

steveo3002

10,659 posts

181 months

Sunday 21st May 2023
quotequote all
sand with 800 wet n dry (used wet) or a grey scotch pad , just sand enough to take off the shine , dont try and sand all the paint off

spray with your gloss black until its covered , 10 mins between coats , if its direct gloss then no clear needed , if youve been sold basecoat it will dry dull and need 2-3 coats of clear

anonymous-user

61 months

Sunday 21st May 2023
quotequote all
Rub down with a Scotchbrite cloth to get a good key. Undercoat to create a flat surface (you generally only use primer for unpainted material) then gloss paint over the top. I think you'd only need lacquer over the top if a metallic or pearlescent paint.

inline6bmwfan

Original Poster:

93 posts

29 months

Sunday 21st May 2023
quotequote all
steveo3002 said:
sand with 800 wet n dry (used wet) or a grey scotch pad , just sand enough to take off the shine , dont try and sand all the paint off

spray with your gloss black until its covered , 10 mins between coats , if its direct gloss then no clear needed , if youve been sold basecoat it will dry dull and need 2-3 coats of clear
So no primer or anything basically?

inline6bmwfan

Original Poster:

93 posts

29 months

Sunday 21st May 2023
quotequote all
pocketspring said:
Rub down with a Scotchbrite cloth to get a good key. Undercoat to create a flat surface (you generally only use primer for unpainted material) then gloss paint over the top. I think you'd only need lacquer over the top if a metallic or pearlescent paint.
Is undercoat not the same as primer?

V8covin

7,860 posts

200 months

Sunday 21st May 2023
quotequote all
There is no need for primer or 'undercoat' on a previously painted item so long as the surface is intact.
Red or grey scuff pad,degrease,paint.Job done

inline6bmwfan

Original Poster:

93 posts

29 months

Sunday 21st May 2023
quotequote all
V8covin said:
There is no need for primer or 'undercoat' on a previously painted item so long as the surface is intact.
Red or grey scuff pad,degrease,paint.Job done
Amazing thank you sounds a lot simpler than i expected!

anonymous-user

61 months

Sunday 21st May 2023
quotequote all
inline6bmwfan said:
Is undercoat not the same as primer?
Nope.

V8covin

7,860 posts

200 months

Sunday 21st May 2023
quotequote all
pocketspring said:
Nope.
What's undercoat ?

Blackpuddin

17,361 posts

212 months

Sunday 21st May 2023
quotequote all
pocketspring said:
Rub down with a Scotchbrite cloth to get a good key. Undercoat to create a flat surface (you generally only use primer for unpainted material) then gloss paint over the top. I think you'd only need lacquer over the top if a metallic or pearlescent paint.
Would this technique apply for repainting an old original Mercedes wing in a different colour?

paintman

7,765 posts

197 months

Sunday 21st May 2023
quotequote all
^^^^
As V8covin has said, if the old paint is sound & of a type not likely to react with whatever you are painting over it then you don't need to apply primer.
(If the old coat is likely to react - something from the old days of synthetic enamels & cellulose - then you will need to either strip back to bare metal & start again or use isolator over the old paint. Also a concern if the item has had a SMART repair, as some used a single pack clearcoat which wasn't resistant to solvents or petrol.)

Clean, scuff the surface to provide a good key for the new paint, degrease, paint.

Base coat - which can be solid colours, metallics, xirillics, pearls etc - dries matt & will need clearcoat.
Top coat - which is solid colours - is glossy from the gun & doesn't need a clearcoat.



Edited by paintman on Sunday 21st May 10:44

anonymous-user

61 months

Sunday 21st May 2023
quotequote all
V8covin said:
pocketspring said:
Nope.
What's undercoat ?
You should know if you gave the advice.

V8covin

7,860 posts

200 months

Sunday 21st May 2023
quotequote all
pocketspring said:
You should know if you gave the advice.
I know,and I also know it's not a term usually used in the vehicle painting trade, it's usually used by painters and decorators.
I think what you're referring to is ground coat which is used under certain colours that don't cover well.....ground coat is often black because black DOES cover well so you'd never use a ground coat under black

inline6bmwfan

Original Poster:

93 posts

29 months

Tuesday 23rd May 2023
quotequote all
So ive done it, first time spraying anything and i made a few basic mistakes. First of all the can from halfords was crap, light spray then heavy, it didnt help i didnt clean the nozzle in between coats, also sprayed outside and tiny bits of fluff or something got on occasionally.

There is also a few run marks where its ran, none of this is massively noticeable but i was wondering if it would be easy to correct? Like if i give it a good sand and then do 3 to 4 more coats will it be okay? Without sanding it all the way back to the original colour?

bern

1,271 posts

227 months

Tuesday 23rd May 2023
quotequote all
I did my wing mirror trim bits just over 12 months ago using some vinyl peelable paint. Just roughed them up slightly with scotchbrite, degreased, and painted them. If it doesn't go well or you don't like the finish you can just peel it off.

12 months later they still look like new. The slightly rubberised coating stands up very well to stone chips etc. I did the grill surround at the same time and it is unmarked.





It's brilliant stuff.

https://www.matt-pack.co.uk/



paintman

7,765 posts

197 months

Tuesday 23rd May 2023
quotequote all
inline6bmwfan said:
So ive done it, first time spraying anything and i made a few basic mistakes. First of all the can from halfords was crap, light spray then heavy, it didnt help i didnt clean the nozzle in between coats, also sprayed outside and tiny bits of fluff or something got on occasionally.

There is also a few run marks where its ran, none of this is massively noticeable but i was wondering if it would be easy to correct? Like if i give it a good sand and then do 3 to 4 more coats will it be okay? Without sanding it all the way back to the original colour?
Sand smooth using fine wet&dry wet.
Apply enough light coats to cover.
Depending what the paint is there is a risk that if you apply heavy coats any sanded edges where you've gone through to the original finish will pickle.
If that happens it will be easier to remove it all & start again.
Warming the aerosol can help with the spraying.

https://uk.ppgrefinish.com/en/paint-defects/pickli...
In your case the 'underlying paint' referred to is the first lot you sprayed on.

inline6bmwfan

Original Poster:

93 posts

29 months

Tuesday 23rd May 2023
quotequote all
paintman said:
inline6bmwfan said:
So ive done it, first time spraying anything and i made a few basic mistakes. First of all the can from halfords was crap, light spray then heavy, it didnt help i didnt clean the nozzle in between coats, also sprayed outside and tiny bits of fluff or something got on occasionally.

There is also a few run marks where its ran, none of this is massively noticeable but i was wondering if it would be easy to correct? Like if i give it a good sand and then do 3 to 4 more coats will it be okay? Without sanding it all the way back to the original colour?
Sand smooth using fine wet&dry wet.
Apply enough light coats to cover.
Depending what the paint is there is a risk that if you apply heavy coats any sanded edges where you've gone through to the original finish will pickle.
If that happens it will be easier to remove it all & start again.
Warming the aerosol can help with the spraying.

https://uk.ppgrefinish.com/en/paint-defects/pickli...
In your case the 'underlying paint' referred to is the first lot you sprayed on.
Thank you i will give it a go.