11 replies to this topic

[Merlin01]

I know I've brought this up before but recently found some YT videos of people using progressively finer grits of sandpaper to sand back the outer layer of plastic before polishing.

I have been using Mequiars Plast-X which does bring them up nice, however after a couple of washes they quickly return to the old faded/foggy look. I'm curious if the sanding back will actually get rid of the problem or simply create an alternative one - like when the polish washes off your left with scratched plastic instead of faded plastic.....

Here is one example of using the sanding method but he also uses a buffer with cutting compound before he applies the Plast-X. Apparently this will remove the scratches the sandpaper applied....
YT link

Anyone tried the sandpaper method with cutting compound/Plast-X and a buffer?

[Cam.]

You will find that most of the time it's just dust, and crap that's built up really. Before you go out and spend some $$$ on plastic polish. Grab some dish soap, a brand new "rough sponge", a chamois and a microfiber towel. First, get some dish soap on a soft sponge and rub a nice thick layer using heaps of elbow grease on the headlight. This should loosen any surface dirt. After letting it sit for a minute or two get that rough sponge and give it a good rub! Now wash the car as you would normally. After chamoising the car use that microfiber towel to rub your headlights that one last time, Just to grab any left overs. Sure that guys method is the right way to do it, But dish soap can do wonders.

[Alex]

Cammy. You have plastic headlights? Or glass? Dish soap won't touch plastic headlights. They genuinely yellow. It's in the plastic, and how they deteriorate due to the effects of UV rays, and the degrading of the polycarbonate lens. The joys of plastic headlights. Thankfully, mine are AOK, but its a neat little trick to give them a spruce up! Can't see why it wouldn't work Merlin! (if I were you, I'd test it either on a headlight that's been damaged at a wrecker, or someone other person's car! )

[Cam.]

Hmm, Maybe my headlights only had a bit of crud on them. I've seen my boss do the youtube method on cars, It seems to work. I don't like the thought of sandpaper near a cars paint, Maybe taking them out would be a nice and safe approach when you get around to it Merlin?

[Merlin01]

(if I were you, I'd test it either on a headlight that's been damaged at a wrecker, or someone other person's car! )

hehe, Brothers wife's imprezza here I come...

I don't like the thought of sandpaper near a cars paint, Maybe taking them out would be a nice and safe approach when you get around to it Merlin?

Yeah good point, I didn't like the thought of such a big buff pad near the paint either.. 'spose you could mask around them, but probably take just as long as taking them out......

Never bought cutting compound before - assume I can get small quantities from auto store?

Also, my housemate has small buff pads that attach to a drill... probably better suited to this job than a full size commercial buffer - well, better suited to me anyway..

[SUBARU]

Don't go near your headlights with sandpaper. The plastic covers onthe gen3 is the "new" type plastic that doesn't fade. Older model cars often had headlight fade due to the plastics not being treated with UV protection. You'll see it a lot on ef falcons, Toyota soarers to name a few. Not the case with your car. If there is any dullness in your lights then it's due to scratching and wear and tear, or you just generally frigging around with them. Plastic polish should do a good job at restoring them and doesn't need to be used often as it chemically strips the plastic down, effectively thinning your headlight lense. I'd like to see pictures of said fading as I seriously doubt you've got any UV burn. It sounds like you have not much detailing experience, so I cannot recommend strongly enough that you DO NOT go anywhere near your car with sandpaper, cutting compounds or a buff. Keep in mind that windex and regular paint polish can do wonders. Btw, what year is your car? The rev a-c gen3 rx's had smokey looking headlights compared to rev d-e.

[Merlin01]

I'd like to see pictures of said fading as I seriously doubt you've got any UV burn. It sounds like you have not much detailing experience, so I cannot recommend strongly enough that you DO NOT go anywhere near your car with sandpaper, cutting compounds or a buff.

Btw, what year is your car? The rev a-c gen3 rx's had smokey looking headlights compared to rev d-e.

LHS


RHS


I still don't know what Rev. it is but assume it's an A.
June 1999 is what the compliance plate says, which I believe is about a month before the MY00 came out.

[SUBARU]

No uv burn there. Looks like scratching. Get at it with the plastic polish, do as best you can with it and then leave them alone. Sanding and polishing may cause more damage. Oh by the way, it's a revision a.

[Merlin01]

No uv burn there. Looks like scratching. Get at it with the plastic polish, do as best you can with it and then leave them alone. Sanding and polishing may cause more damage.

Oh by the way, it's a revision a.

Those pics were taken when I first bought the car.
Then I was told to try the Mequiars Plast-X. which does work well:

Post Plast-X Pics removed

However, like I said before, after a couple to a few washes, the polish disappears and they are back to how they started...
And that is what I'd like avoid if possible. It's like a band-aid fix for something that requires surgery!!

My housemate just told me that he hasn't seen the sandpaper method used in the field (major dealership detailer), however newer cars shouldn't be susceptible to this problem. He also suggested you might be able to achieve the same result by using varying degrees of compound instead of sandpaper - Course, Medium, Fine.... But also warns - test it somewhere else first!!

[SUBARU]

The plastic polish you are using doesn't "wear out". It literally dissolves a layer of the plastic to restore a shine or clear the lense... Something else you are doing is making the lense get scratched. It's a pretty tough job to get these lense covers all swirled to the point of looking cloudy. Your housemate is right. Sandpaper on headlights is not used much at all. If your lights are so bad that you need sandpaper and hours of labour to bring them back to a usable level, it's often better to replace them with a new/second hand set. But cutting compound on plastic covers? Nup, will cause more scratching. There is no point showing us pics of when you bought the car and then more pics just after you've applied the plastic polish. Show us new pictures of the problem at hand. Seriously mate, seems like a small issue here. If you reckon the lights are faded, just make it part of your routine to polish the headlights every time you wash the car. If you're not happy with that, get a new set of JDM HID's from Import Monster.

[Merlin01]

The plastic polish you are using doesn't "wear out". It literally dissolves a layer of the plastic to restore a shine or clear the lense...

Hmm, if that's the case then shouldn't the haze be gone/dissolved permanently, leaving only a clean clear layer? But then in a matter of a couple of weeks the cloudiness reappears in the exact same size and shape. I'm sorry, but I think there is something missing here...

There is no point showing us pics of when you bought the car and then more pics just after you've applied the plastic polish. Show us new pictures of the problem at hand.

Fair enough, removed the 'after' pics from above.
Here is a couple of the LHS today - Not that noticeable from the front but definitely more noticeable from the side:

Seriously mate, seems like a small issue here. If you reckon the lights are faded, just make it part of your routine to polish the headlights every time you wash the car. If you're not happy with that, get a new set of JDM HID's from Import Monster.

It is a small issue, however after making it part of my cleaning routine for the last 4 months I went looking for other solutions than continual polishing that didn't involve replacements. Wouldn't anything from the same era be prone to the same problem? No matter where it came from?

[RX25SE]

Correct me if I'm wrong, but didn't Mark (CRUSIN) spruce up the surface of his headlights? Maybe ask him?