Some of you know that I'm new to modding, so I've been researching the topic of getting my side sills (and rear bumper) painted to match my car. ttrank discusses this in his handy !!Look here before starting a new thread!! 2003-2006 Sedan FAQ's thread.

Here's the gist:
Due to time constraints, I'm trying to find local paint shops that can do a good job with this project. Others on this forum have warned against blindly choosing a shop merely based on price because often times you get what you pay for.

So, are there certain types of questions can I ask that will help me differentiate the "quality" paint shops from the rest of them?

For eg, what do you think of these questions:
1) Will you be using paint adhesion promoter?
2) How many coats of paint will be applied? (What is the minimum?)
3) How many coats of clear will be applied? (What is the minimum?)
4) How long do you warranty your paint job (aside from normal wear and tear)?

On second thought, is it insulting (or bad etiquette) to ask the above questions?

Oh, lastly, I also plan to check out pictures of their past work if such pics are available.

Thanks for making it this far down my long winded post. Please let me know your thoughts.

 

I'm shocked there are shops that can't handle painting these things. Why? Because I painted them myself and I had absolutely no experience doing it either. It's all in the prep. Here's my DIY: https://g35driver.com/forums/showthr...ight=DIY+sills

I know most people won’t be doing their own painting of the sills, but I thought it might be useful to some that have access to the equipment or are just curious about the automotive painting process and what it takes to paint plastic parts. First off, let me say I’m a total amateur and this is the first thing I’ve ever painted on a car with a spray gun. Everything is fairly easy, but the plastic prep process takes a very long time (5+ hours). The painting takes a total of 10 minutes. I have the Aero bumper so I did not paint have to paint the front, but with this DIY, the process would be explanatory. I painted the lower sills, lower portions of the mud guards, and rear bumper which remained on the car for painting.

Equipment needed:

Air Compressor with at least 13 gallons - 1.5HP (my compressor is 26 gal./1.5 HP)
Inline water/oil separator for compressor (without the separator, you could get fisheyes in the paint from water condensate)
Spray gun – I used a $35 Husky siphon feed “detail” spray gun



10mm socket and ratchet
Various screwdrivers
Automotive clip removal tool ($5 from the auto parts store)
P-400 automotive scuff pads
Masking Tape
Plastic sheeting
Half-face respirator with organic vapor cartridges
Automotive soap
Cleaning pad
Isopropyl alcohol
Nitrile gloves
Paper towels
Tack cloth

Paint Supplies:

Graduated paint container
Can of adhesion promoter
Paint Hardener
Paint reducer
OEM factory paint – the factory paint is single stage. That means it have both a base color and clear built in. I used higher end PPG materials, about $100 total and I have a ton of paint left and I only bought a pint and that was amount smallest available.


Step 1- Removal of door kick plates
1) Front kick plates – simply grab either edge of the plate and carefully pull upwards. There are three clips holding them in.

2) Rear kick plates – remove the round clip (see pictures) by pushing in the middle part of the clip and then pry out with thin flathead screwdriver. Next, lift the plate from the back and lift up, pulling towards the front of the car.





Step 2 – Remove mudguards, if equipped

Step 3 – Removal of the rear lower ¼ fascia
1) Remove the 10mm bolt under the fascia.

2) Push the fascia forward towards the front of the car and it will release.

Step 4 – Removal of the side sills
1) Remove the 6 10mm bolts from the lower portion of the sill and remove the two screws on each end of the sill in the fender wells.

2) Using the clip removal tool, carefully remove the 8 clips that attach the upper portion of the sills to the body. See picture.



The picture below shows the sills and rear fascia removed.





Step 5- Cleaning the panels, Wash with soapy water then just water
1) Wash all the panels with hot soapy water. Use as hot of water as you can tolerate. Wash all sides of the panels because you don’t want to have dirt blow off the panel when you’re painting. It is very important you adequately clean the panels. The washing is needed to remove water soluble contaminants. The ways to test if the panel is clean is run water over the panel. If it beads, it’s not clean. The next test is to take a gloved finger and run it 6” down the panel. Run water over the panel. If you can see where you ran your finger after the water runs then the panel isn’t clean.

2) Wipe the panels down with isopropyl alcohol. The alcohol will remove non-water soluble contaminants.

3) Scuff the panels with the P-400 pads. Scuff in a horizontal motions, then vertical, then circular. Do not use heavy pressure. When you’re done, the panel should look flat and have no shine.

4) Wash the panels with hot water, then alcohol wipe, then go over the panels with a tack cloth.

Step 6 - Car prep and home prep
1) Tape and sheet off all parts of your car that you don’t want overspray on. The paint gun really doesn’t generate a lot of overspray, but you need to protect the car.

Car 50% wrapped


2) Tape off the doors and vents in your garage to keep the vapors out of the house. Auto paints are very volatile and the odors linger for a long time because the paint off gases for about 8 to 10 hours.

Step 7 - Adhesion promoter application

Spray each panel with two light coats of the promoter, waiting 5 minutes between each coat. The promoter will go on hazy and dry fairly clear. The promoter is a must if you want the paint to stick to the plastic. The promoter will be ready to paint in about 20 minutes.

Step 8 - Paint
1) Mix the paint. For my paint, I needed 4 parts base, 2 parts reducer, 1 part hardener. Fill gun.

2) Set the compressor to about 50-55 psi and adjust the spray pattern and material feed of the gun accordingly. Spray the paint on a piece of cardboard to get the correct pattern.

3) Using a side to side motion, not breaking your wrist, apply the paint. Walk the length of the panel. Don’t let your arm span the distance. DO NOT use the painting method commonly shown on auto TV shows where the tech is applying the paint in a side to side motion breaking their wrist. This is incorrect will apply more paint to the middle and less paint to the sides.

2 hours to prep the bumper and 2 minutes to paint



4) Let the paint flash for 10 to 15 minutes and apply a second coat, then wait another 10 to 15 minutes and apply a final coat.

5) The paint will be dry to the touch within 2 hours, but the paint will still be very soft. If it’s cold outside (less than 70 degrees), the paint will take longer to cure. Be VERY careful in handling the panels because the paint will be soft for at least 8 to 10 hours.

You’re done. Keep in mind that the sills have a very faint grain pattern which mean achieving a total gloss finish is nearly impossible. The finish I got was exactly what I wanted which is semi-gloss.



Before – gray nastiness and tiny OEM exhaust tips



After with 2007 Altima Fat Body tips

 

Thanks for the response, DaveB. I actually already did see your thread--that's where I read about the terms "adhesion promoter" and "flex agent" for the first time.

I could be wrong, but I get the impression that some shops shy away from painting our sills because they're unsure how well their paint job will hold up over time. Like I said, I could be wrong....