Painting Interior Plastic Trims

For those wanting to paint any plastic trims themselves, heres a write-up on how to paint your plastic trims.

*DISCLAIMER* 
THE FOLLOWING IS PROVIDED AS A GUIDE ONLY. I AM IN NO WAY GUARANTEEING SATISFACTION. USE AT YOUR OWN RISK! I TAKE NO RESPONSIBLITY FOR ANY DAMAGED PARTS OR MISUSED PRODUCTS.

Things You'll Need:

• Hot/Soapy water (dish soap will be fine)
• Prep Solvent (vinly cleaner, wax & grease remover, alcohol wipes etc..)
• 3M Scuff Pad or 800 grit wet/dry Sandpaper
• 2000 and 2500 grit wet sand paper (for flattening clear coat)
• Plastic Adhesion Promotor (I use HB Plastofix or 3M plastic adhesion promotor)
• Automotive Primer (If required to fill-in scratches and imperfections)
• Base-coat Paint (Aerosol Paint is perfectly fine)
• Clear Coat
• Microfiber Towels
• Microfiber Applicator Pad
• Rubbing Compound, Polish or Scratch Remover

STEP 1: Location
Remove the part you wish to paint from the car and find a location to paint it. If painting indoors make sure you have plenty of fresh air coming in and some sort of exhaust to filter the over spray (and wear a mask). If you are going to paint outdoors, make sure it is not wet & windy. You want a nice warm day.

STEP 2: Prep & Keying
NEVER RUSH AND SPEED THROUGH THE PREP PROCESS

• Prep is the most important part of the process when it comes to painting. If you rush this step to save time, you'll just ruin the result. If you do not prep correctly the paint may not stick properly and start flaking off at a later stage. Often with bad prep the only solution is to sand it down and start over again.
• Firstly wash the trims you are painting with some Dishwashing Detergent.
• Rinse and dry the part. Mask any part of the trim that you don't want to paint with painters tape.
• Using a small amount of the 800 grit wet-and-dry paper, scuff the surface of the trim all over. Make sure that you get into all the awkward corners and rub thoroughly all over flat surfaces. When you’re done, the original part will have a dull, scratched surface.
• Wash and dry the part thoroughly. 
• Once it is dry, wipe it down with alcohol wipes or paint prep wipes.

STEP 3: Adhesion Promotor/Primer and Base-Coat

• Now you want to apply about 2 or 3 coats of your Adhesion Promotor. Wait about 3-5mins between coats, letting the previos coat become tacky before applying another coat.
• Next you want to apply either a filler primer or move straight on to your base-coat. If you surface has lots of imperfections, you might want to use filler primer otherwise move on to the base-coat. 
• Next... Apply very THIN and EVEN coats of your choosen base coat colour, allowing enough drying time between coats (Until it becomes tacky)
• After last layer of base-coat allow enough time for base-coat to dry before applying clear coat. Different paint systems have different recommended times. Please follow the recommended waiting time of your paint system. Preferably wait a full 24hrs (or more depending on drying temperature)
• Be sure not to apply a thick coat of paint. Thin & even coats give better results.
• If any runs or sags happen let part dry and wet sand with 1200 grit sandpaper, let it dry, use a tack cloth and re-paint.

STEP 4: Clear Coat
Clear coat acts differently than the base coat. A lot of people think its just clear color paint. It has very special techniques to get correct and you have to take your time and practice.

• Once your base coat has dried, you are ready to begin clear.
• You want to apply VERY thin coats of clear. Make sure you are applying an even coat to the entire surface.
• Apply 4-5 coats of clear, allowing 5-10mins or so (depending on temperature) between coats.
• After the base-coat has dried (24hrs or more depending on temperature), you want to begin wetsanding with your 2000 grit paper and move up to 2500 grit. Be sure the paper has been soaking in soapy water for approximately 30mins prior
• Use very light sanding pressure in one direction. You are not removing paint here, you are simply smoothing and flattening out the last layer of clear.
• Once you have a uniform smoothness to the clear (you will be able to see the sanding marks), move on to the final polishing step.

STEP 5: Polishing
This is the step that will give you the deep gloss mirror shine and show you a finished product.

• Grab your compound or swirl remover and applicator pad
• Apply a dime sized ammount on your applicator
• Begin making small overlapping circles with moderate pressure on the painted surface.
• You should see the sanding marking begining to disappear over time.
• In order for the marks to completely be removed, it may take more than one application.
• This will remove all sanding mark and produced a brilliant shine from the paint.