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Fixing and respraying plastic interior trim

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Interior plastics looking worn and tired? Colours old-fashioned? Ash grey trim not hektic enough for your Veilside R33 GTS?

You can change it!



Trim Cleaning:


I've found the best combo is also the cheapest; Liquid hand soap, dish scrubbing brush and a hose. Hot water is fine, just not boiling.

My results with the 'recommended' prep cleaners has been very mixed, so I stick with what works. Cheapness is a bonus.



Rattlecan Vinyl Dye Prep:


Clean the surface with liquid soap and water, then lightly run steel wool over the surface to remove any small nicks, scratches or particles of grit/plastic on the surface.

The idea is to produce a nice texture, whatever the colour.


Almost all imperfections will be displayed after coating, so take care if sanding a textured section, as it will be obvious in the finished product.

To repair deep cuts or scratches, you can fill them with molten plastic of the same grade (don't mix different types of plastic) using an old soldering iron to fuse the molten material with the inside walls of the scratch. Once filled, sand down and hope you can apply adequate texture when dying.


Be sure to clean the surface again before painting.


In brief, if the surface is in the condition you want, then a good clean is all that's required. Sometimes buying a replacement panel of a different colour is better than repairing a damaged one of the same colour. That's the benefit of recolouring - it doesn't matter what it starts as!



Plastic Repair Using Molten Plastic:


If body filler can't be used, or isn't desired, the alternative is to use molten plastic. It's low tech, but it works.



- Scrap interior panels (from the same car if possible) that can be cut into pieces

- Fat soldering iron with a few different tips (45 degree flat tip is best)

- Ventilated area, and breathing protection (fumes are bad for your health)


The process is quite straightforward:

A. Cut off a section of scrap plastic

B. Use the soldering iron to melt off a small section

C. Scrape the molten plastic sitting on the tip into the section to be filled

D. Insert the soldering iron tip into the section to be filled, so you melt the inside edges (needed to fuse the plastic together)

E. Rearrange the molten plastic to smooth out disruption caused by Step D


Once filled, cut and sand down the excess to the desired finish.


It should be noted that melting plastic is effective for more than simply filling gaps. The same technique can be used to fuse cracks, reattach broken sections of trim, insert new pieces of plastic, or even to cut holes in plastic. The strength of the bond can vary, but the advantage is the rapid setting time and relatively clean fitting process.



Rattlecan Vinyl Dye Application:


Any can of vinyl dye with a decent nozzle will work fine imo. VHT is a good choice.


Dust it on lightly from a distance, repeat a few times to get a patchy-looking base coat happening, then go for thicker coats. Application and preparation is less forgiving than paint; get it wrong and sections will bubble and peel right off like a thin veneer. Get it right, and it will be like a new version of the existing surface, showing everything below it.


For a textured finish, turn the can upside down, spray a little on a cardboard box, get some splatter happening, then dust the surface. If done correctly, you'll have lots of little raised dots which will give texture to sanded sections on textured panels.



Rattlecan Paint Prep:


Clean the surface with liquid soap and water, then lightly run steel wool over the surface. Be sure to clean the surface again before painting. Cuts and scratches can be filled with bondo and sanded, as paint hides more than vinyl dye and can achieve a better 'texture' finish. You won't be replicating fake leather grain, so in some cases it's easier to simply sand everything smooth.


Rough or sanded surfaces on ABS plastic don't necessarily need an adhesion promoter, whereas plastics with greasy feel do. I usually prime the surface for consistent colour and to smooth things out, but this isn't always required, and in some cases isn't wanted.



Rattlecan Paint Application:

Ricey 'Painted' Finish

Just paint as you would anything else. Build up layers and achieve a solid paint finish. It will look like it has been painted, and some people are into that.


'Dry' OEM Finish

I just made up this term to describe a style of factory interior paint finish. The S15 silver trim is a good example , whereby the silver on the console has an almost powdery look, but isn't a satin or matt.

Lightly dust the paint on from a distance (think crop dusting, not cleaning things with a brush), ideally with a high-quality touch-up can or any paint with a really fine mist pattern. I took this approach painting my s15 lower trim and most non-enthusiests think it's factory.


Textured Finish

You want a combination of light application and spray splatter. You can buy texture paints, or just turn the can upside down and get some splatter happening.


When you tip a rattlecan upside down and spray, paint moves away from the pickup point and produces an inconsistent paint feed.

The end result is a whole bunch of little paint blobs, rather than a smooth mist. Once dry, you're left with a surface covered in tiny bumps.

If you spray the paint in light coats from 20cm away, this texture will mostly be retained instead of being filled in. Think of 'crop dusting'; a light mist from far away.


So it makes more sense:

A. Find vertical surface that can get paint on it (e.g. cardboard box, wall, neighbour's laundary)

B. Tip the can upside down

C. Spray a little bit onto the vertical surface until the spray turns to crap

D. Return to the plastic trim and carefully spray a little paint onto it whilst the spray is still crap (it will soon recover, so you can only do a little at a time)

E. Repeat Steps A-D until the trim has a nice texture covering it

F. Leave the paint to cure

G. Paint the trim with light coats from 20cm away or more. Build it up in stages so you don't lose the texture.



Mixing Paint Finishes


One technique to net interesting results is to mix gloss, dry, smooth and textured finishes. Cohesive design usually dictates using only a few colours, so changes in texture really break it up. I feel that 'dry' paint suits textured sections best, whereas smooth sections lend themselves to gloss, or gloss with a clearcoat. Apart from being harder wearing, you can break up the look of the interior whilst still using the same colour paint. The effect is similar in concept to a manufacturer using brushed steel or chrome to break up silver paint.


As an example, my lower S15 dash trim is a light arctic blue/silver with a dry oem-texture finish, whereas he spokes on the wheel, horn button surround, ciggy plug and spinner knob are the same colour, but with a gloss clearcoat.



Selecting Paint Brands:


I've found that brand doesn't matter too much, but nozzles and spray consistency varies a lot. Experiment with what's available.

VHT and 3M seem reasonably consistent, as are the Dupli-Colour touchup paint. Although expensive, the latter are my paint of choice for interior pieces, as the colour is very consistent between cans. This makes touchups less noticable and blending a possibility years later.



Vinyl Dye VS Paint. Points To Note:


- Paint hides texture and imperfections better than vinyl dye

- Vinyl Dye on a surface feels like plastic, because it's a polymer itself. Paint always feels like paint.

- Vinyl dye does really work with body fillers, unless they're polymer based

- Vinyl dye can be worked into fabric fibres with greta results, whereas paint usually hardens the fabric's fibres

- Paint is more effective at creating surface texture than vinyl dye

- Bad prep can lead to vinyl dye peeling off in sheets, like dead skin. Not so with paint.


Edit: Some pictures to give you an idea. Excuse the lack of awesome camera:


Ice Blue Metallic:





Shaved Logo:







Satellite Brown Metallic:








Edited by pmod

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