plastic painting

 
Painting the plastic is not for the faint of heart.  To do it right, the entire interior, including the dash, must be removed.

For the plastic panels, I used SEM products.

(2) SEM Soap

(2) Sand Free

(2) 39863 Plastic Adhesion Promoter

(2) Plastic/Leather Prep

(17) Color Coat (Satin black)

The key to using the SEM system is prep, prep, prep.  The surface needs to be perfectly clean.  This is especially true for pieces that have had Armor-All applied.

Any piece small enough to fit got ran through my dishwasher.  They came out perfectly clean and ready to prime.

In the SEM world, there are basically two kinds of plastic -- ABS-type and everything else.  If the plastic softens with lacquer thinner, then it is likely ABS.

On the back of each Look on the back of each panel. There is a plastic code:

ABS = Acrylonitrile Butadiene Styrene.  SEM paint sticks to ABS like OEM.  Most of the hard plastic -- dash and dash panels, OH console, Expy console -- is ABS. To those reluctant to paint, note that many of the interior parts -- ashtray, glove box cover, surfboard, etc., are painted from the factory. And many of the replacement interior parts are now listed as "paint to match," which I assume means that the dealership has to paint them before installing.

PP = polypropylene. Not known for good adhesion. Requires careful prep. About half of the large panels are PP, as well as some of the smaller dash panels.

HCPP = High Crystalline Polypropylene. This is the PITA stuff. It is a cheap plastic from, where else, China. This includes the other half of the large panels.

TPO = ThermoPlastic Olefin. OK adhesion (TPO is a cocktail of plastics, one of which is usually PP). Door sills are the only parts I have noticed were TPO.

TPE = Thermoplastic elastomers (TPE):  The surfboard and the airbag cover (unmarked plastic) are TPE.  I just scrubbed them with lacquer thinner and went straight to the Color Coat.

For the parts that are already painted from the factory (dash, ashtray, glove box door, etc), use a very light coat of Sand Free, and then very light coats of paint, allowing each to dry between coats.  If you lay anything on wet, it will begin to wrinkle the factory paint (I learned this by ruining the glove box door, so be careful here).

The SEM paint sticks to ABS and to some TPO because it can dissolve the surface layer of the plastic and chemically bond.

PP and HCPP are a problem because they are immune to lacquer thinner, which is the SEM solvent.  These are the panels to that need extra super careful attention.  Clean them well.  Then wipe down several times with lacquer thinner.  Then sand with 400 grit paper.  Then hit them with lacquer thinner again.  Finally, apply Plastic Adhesion Promoter and Color Coat per the standard SEM instructions.

Panels from a Harley-Davidson truck are an option, but you need to mix years.  AFAIK, the 2000 is the only H-D with our doors.  If I can't get OEM or near-OEM durability with the HCPP panels, then I'll probably buy Harley panels and spray them with SEM (the problem with the gray panels is just that the gray shows through when scratched).

Removing the dash was a huge chore.  I could not find any way to remove it without cutting this piece:

Here's the dash naked:

Yikes.

 

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05/17/2008 Tim Skelton