Restoration of exterior plastic parts and targa top X1/9

Jeff Fischer

Daily Driver
Hi Guys
Wondering if there is any advice in restoring air scoops, targa top and other plastic items on the exterior of the car. I would assume that I would throughly clean the part with a degreaser but not sure whether I would sand the part afterwards since it is a plastic. Also not sure if there is anything I should do with the Targa top. Let me know if you have any suggestions
Thx jeff
 
I've had good results with vinyl paint. Very lightly sand the part, clean with alcohol (depending on the part, I will use a primer), then spray a light dust cost, followed by 1,2 or 3 heavier coats. The finish seems to last well and will look like new for about a year. It it may dull or flake after some time. I've sprayed all my black exterior plastics over 2 years ago, and they still look new. The elephant ears (foam rubber) are the only parts that have dulled and had any flaking. Again after about a year and roughly 60-80 car washes. GL
 
As Eastep suggested, I'd go easy on the sanding as the parts do have some texture to them. What I would do is run the scoops through the dishwasher (low water temp, no heat drying) and then paint.

For the targa top, you have to decide if you want to keep the texture or not. Some have removed the texture and sanded the top smooth and painted. Others have suggested spray-in bed liner, though I have not seen what what would look like.
 
I've had good results with vinyl paint. Very lightly sand the part, clean with alcohol (depending on the part, I will use a primer), then spray a light dust cost, followed by 1,2 or 3 heavier coats. The finish seems to last well and will look like new for about a year. It it may dull or flake after some time. I've sprayed all my black exterior plastics over 2 years ago, and they still look new. The elephant ears (foam rubber) are the only parts that have dulled and had any flaking. Again after about a year and roughly 60-80 car washes. GL

I've had good results with vinyl paint. Very lightly sand the part, clean with alcohol (depending on the part, I will use a primer), then spray a light dust cost, followed by 1,2 or 3 heavier coats. The finish seems to last well and will look like new for about a year. It it may dull or flake after some time. I've sprayed all my black exterior plastics over 2 years ago, and they still look new. The elephant ears (foam rubber) are the only parts that have dulled and had any flaking. Again after about a year and roughly 60-80 car washes. GL

Hi Eastep
Thx for the suggestion on the paint and how to clean them. What grade of sandpaper would you use? Wet 600 or 800?..
 
As Eastep suggested, I'd go easy on the sanding as the parts do have some texture to them. What I would do is run the scoops through the dishwasher (low water temp, no heat drying) and then paint.

For the targa top, you have to decide if you want to keep the texture or not. Some have removed the texture and sanded the top smooth and painted. Others have suggested spray-in bed liner, though I have not seen what what would look like.
Great suggestion how to clean them, the wife might not like it. I would like to keep the texture so I will try some light sanding. Putting it into the dishwasher might be trouble. Will use alcohol and a degreaser.
 
Hi Eastep
Thx for the suggestion on the paint and how to clean them. What grade of sandpaper would you use? Wet 600 or 800?..
Hello, your welcome and like 1200 grit. Basically just enough to knock down the .... Oxidation?? Deterioration??.. layer that plastic tends to get.
 
I went thru this with my 85 this past summer. I cleaned all the plastic parts with Simple Green. Basically I took the parts all off the car and scrubbed them in a bucket with Simple Green and water. Then rinsed them really well and let them dry. I used Rustoleum Bumper and Trim black, instead of Dupli-Color brand. If I do it again I will try harder to find the Dupli-Color as I wasn't crazy about the way the Rustoleum went on.

I painted the front grill, side scoops, side mirrors housings, door handles, wiper arms, small side vents at base of targa sail panel, and the corner trim pieces by the engine cover. I painted the engine cover and rear grill with Rustoleum satin black. Here are a couple pictures.
IMG_1840.JPG IMG_1841.JPG

I think the only parts I sanded were the two tops of the two corner trim pieces by the engine cover. The Bumper and Trim paint kept puddling on those parts and I must have repainted them 4 times before I called it good enough.

On the small side vents on the sail, I taped off the silver Bertone badge prior to painting. Then used a black paint stick to fill the Bertone emblem and text. Filling those areas with fresh paint made a big difference in the look of the final product. This the best picture I could find of the small vent.
IMG_1832.JPG
The repro bumpers were installed as delivered from MWB, so I didn't have to paint those. :) Oh, and I somehow forgot to paint the reverse lights. :(
 
Hello, your welcome and like 1200 grit. Basically just enough to knock down the .... Oxidation?? Deterioration??.. layer that plastic tends to get.

Comet cleaner with a green scotch brite pad... Or Softscrub if they still make it. Leaves the surface super clean and ready for paint in most cases.
 
Every surface is a little different. But most plastic parts shouldn't require much sanding. Short of doing repair work, pre-paint sanding is mainly done to give the surface a slight 'roughness' so the paint has something to attach to. But unlike paint, the surface of plastics tend to be porous so that isn't needed. If it really needs a more aggressive prep, then a ScotchBrite pad like stingray250 described should work well. Otherwise you may be creating a surface that is too rough and then needs to be primed and filled. And speaking of primers, plastics will benefit from a coat of 'adhesion promoter' before painting (if you go with paint).
 
Every surface is a little different. But most plastic parts shouldn't require much sanding. Short of doing repair work, pre-paint sanding is mainly done to give the surface a slight 'roughness' so the paint has something to attach to. But unlike paint, the surface of plastics tend to be porous so that isn't needed. If it really needs a more aggressive prep, then a ScotchBrite pad like stingray250 described should work well. Otherwise you may be creating a surface that is too rough and then needs to be primed and filled. And speaking of primers, plastics will benefit from a coat of 'adhesion promoter' before painting (if you go with paint).
Thx Dr. jeff
That makes sense, the top is in great shape but looking dull so giving it a fresh coat of paint will bring it back to life. I am just getting back into working on the car but the weather up here has been cold so little has been done since I saw you in LV.
 
Hey Jim
I liked what you have done with your car, it inspires me of where I want to be with mine when I am finished. I have never heard of the product simple green but I will see if I can find it up here in Canada. I can get the Duplo product up here so I will look into that. Again the car looks great!
 
Hey Jim
I liked what you have done with your car, it inspires me of where I want to be with mine when I am finished. I have never heard of the product simple green but I will see if I can find it up here in Canada. I can get the Duplo product up here so I will look into that. Again the car looks great!

Thanks Jeff,

All it takes is time and money, then more money for someone else's time. :) I bought this 85 X in 2013 I think. It was in primer when I bought it and half-way to the early bumper look. I finally got it painted last summer and put in new seat upholstery. It is a nice driver level car now, certainly not a concourse car. Good luck with your project, we all look forward to seeing it as you progress.
 
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I was wondering... with all of our plastic parts becoming fragile due to age, has anyone priced out 3d metal printing? Aluminum would probably be a great alternative with a black powder coat like the Beretta 9mm. If no one has then I will take some parts to a local 3d fabrication shop here in Tampa to see what the cost would be and if we order bulk would reduce the cost any. I have a few pieces in mind right out the gate that are greatly needed by our XWeb'ers.
Mike
 
Mike, it will be interesting to see what you find out. 3D printing has come a long way and they are doing amazing things with it. But from what I've seen it is quite expensive to have done. So it might depend on what parts you are considering; are they no longer available new or good used, are there no other options to remake them more affordably, are they that important to be worth the investment, etc. Let us know what you find.
 
the top is in great shape but looking dull
Jeff, there was a thread about refinishing tops awhile back. That textured finish seems to be a coating of some sort. Attempts to remove it required a lot of sanding to get down to the base fiberglass. So unless that is your goal, it might be best to not sand it. Instead try a good cleaning with a scrub brush and cleaner/degreaser. Then maybe go over it with a wax/grease remover pre-paint cleaner to help remove any silicone products that might have been applied in the past. Finally do whatever refinishing coating you choose.

Here is one thread talking about top refinishing (there have been others but I can't locate them):
https://xwebforums.com/forum/index.php?threads/what-is-under-the-targa-top-coating.35221/#navigation
 
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