How to fix Lexan windows

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Mike PhillipsMike Phillips is verified member.

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How to fix Lexan windows


Anytime I get questions via e-mail, a PM or a FB message I prefer to invest my typing time where

A: It's easier for me to share links, pictures and videos.

B: More people can read and thus benefit from the information. (no just one set of eyeballs


So I get an e-mail asking,


Hi! We have a racecar with Lexan side windows.

New to racing,we used shoe polish for our 1st dial in time-it would not come off.

Friend used Brake fluid-it came off,but we now have a hazy smear in that area.

Other friend recommended Mcguires Lexan polish-said it comes in 2 tubes-he thinks.

Do you have a product that would help?


Here's my reply...


In my career, I’ve

Most the people I meet asking for a product have high expectations. By this I mean, they want to apply something and aft wards the Lexan should look crystal clear like brand new glass.

And to this point, in my career, I’ve never found a product that will restore damaged Lexan back to LIKE NEW.

Lexan is HARD and because it’s very hard it’s VERY HARD TO POLISH with the end results looking new or even good.

About the only product that might “help” is Meguiar’s PlastX


PlastX
Meguiars Plastx Clear Plastic Cleaner & Polish - clean & polish all clear plastic panels and convertible top windows.


You would have to machine apply it using a foam polishing pad on an orbital polisher and again, I’ve NEVER seen Lexan that was messed up restored to look NEW – that is totally clear.


I’ll share your predicament on our forum to see if anyone else has some suggestions.



Mike Philips

p.s.

Old school plastic like Plexiglas is EASY to work on but Lexan… nope.


:)
 
Just thinking out loud, Mike--Lexan is polycarbonate, polycarbonate is what they make headlights out of...we can frequently "fix" damaged headlights with sanding and polishing--wouldn't the same apply to a window?
 
Setec Astronomy said:
Just thinking out loud, Mike--Lexan is polycarbonate, polycarbonate is what they make headlights out of...we can frequently "fix" damaged headlights with sanding and polishing--wouldn't the same apply to a window?
Click to expand...


Good thinking but when it comes to Lexan specifically.... like I wrote,

In my career, I’ve

Most the people I meet asking for a product have high expectations. By this I mean, they want to apply something and aft wards the Lexan should look crystal clear like brand new glass.

And to this point, in my career, I’ve never found a product that will restore damaged Lexan back to LIKE NEW.
Click to expand...


I was very careful and specific with the exact words I chose.

And again, when I'm dealing with people with this topic, they don't have a lot of experience with Lexan and often times don't have a lot or ANY experience machine buffing.

Their expectations are HIGH and I'm sad to say, unreal.

Lexan is a different animal.

Headlights = easy

Plexiglas boat windshield from 1960 = easy

Lexan?

I've never seen messed up Lexan restored to BRAND NEW Perfect condition.

Never.


:)
 
It was just an idea. I've never had much luck with PlastX. IIRC there is some Lexan sheet that has a coating on it (perhaps not unlike the hard UV coating on headlights), and that's probably what I'd want for a racecar window. I think you're right to lower expectations on this because likely the chemical damage from the brake fluid is pretty deep, and even if you could sand that out you'd probably have a pretty wavy, non-"glasslike" window...just like I think you've cautioned people about with their (glass) windshields. Good call, Mike.
 
Setec Astronomy said:
It was just an idea. I've never had much luck with PlastX.
Click to expand...

I've had nothing but stellar results with PastX for years but only when working on plastics I know can be fixed.



Setec Astronomy said:
IIRC there is some Lexan sheet that has a coating on it (perhaps not unlike the hard UV coating on headlights), and that's probably what I'd want for a racecar window.
Click to expand...

Correct and I believe it is the coating on the plastic that is the part that is so hard that it doesn't like to be abraded with the end result looking good.



Setec Astronomy said:
I think you're right to lower expectations on this because likely the chemical damage from the brake fluid is pretty deep, and even if you could sand that out you'd probably have a pretty wavy, non-"glasslike" window...just like I think you've cautioned people about with their (glass) windshields.

Good call, Mike.
Click to expand...


Hate to be the bearer of bad news but often times I simply don't know the experience level of the person e-mailing me or what tools they have available.



:)
 
Lexan is probably in my detailing experience the absolutely hardest thing to work on. I can attest to what Mike is saying in that a lightly scratched or lexan window that has lost its UV protective layer is difficult to restore. I have a hardtop on my car where the rear window is lexan. The sun is the worst enemy and it will oxidize making it very difficult to correct. I have tried a few combinations from an orange LC pad with some menzerna SIP that worked well, however I have found that a black LC finishing hybrid pad with plastX works just as good and is easier to work with. The pad gets very dirty quickly, but I find that plastX by hand yielded terrible swirling so I would only recommend this with a DA (I use the flex 3401).

Hope this helps you.
 
Mike Phillips said:
How to fix Lexan windows


Anytime I get questions via e-mail, a PM or a FB message I prefer to invest my typing time where

A: It's easier for me to share links, pictures and videos.

B: More people can read and thus benefit from the information. (no just one set of eyeballs


So I get an e-mail asking,


Hi! We have a racecar with Lexan side windows.

New to racing,we used shoe polish for our 1st dial in time-it would not come off.

Friend used Brake fluid-it came off,but we now have a hazy smear in that area.

Other friend recommended Mcguires Lexan polish-said it comes in 2 tubes-he thinks.

Do you have a product that would help?


Here's my reply...


In my career, I’ve

Most the people I meet asking for a product have high expectations. By this I mean, they want to apply something and aft wards the Lexan should look crystal clear like brand new glass.

And to this point, in my career, I’ve never found a product that will restore damaged Lexan back to LIKE NEW.

Lexan is HARD and because it’s very hard it’s VERY HARD TO POLISH with the end results looking new or even good.

About the only product that might “help” is Meguiar’s PlastX


PlastX
Meguiars Plastx Clear Plastic Cleaner & Polish - clean & polish all clear plastic panels and convertible top windows.


You would have to machine apply it using a foam polishing pad on an orbital polisher and again, I’ve NEVER seen Lexan that was messed up restored to look NEW – that is totally clear.


I’ll share your predicament on our forum to see if anyone else has some suggestions.



Mike Philips

p.s.

Old school plastic like Plexiglas is EASY to work on but Lexan… nope.


:)
Click to expand...

I've never heard of lexan but im going to go out on a limb and say you(OP) should not have used shoe polish. X2 for the break fluid....
 
Novus makes a plastic polish the has 3 different steps with #3 being the most aggressive. I'm not sure how it compares with any of the other products. I have used it on boats with good results. It may work but Lexan is a different animal. The brake fluid may have doomed it. Trying to help OP out,please remove if you don't want that product name mentioned here.
 
***Update***


Thank you to everyone that posted their help, suggestions and feedback.


You know I send the link to this thread to the person that originally sent me the e-mail and rarely do I have hear back from them.

Of course they can join the forum and interact but most of them don't. That's okay but it also give me license to take their e-mails to the forum as I don't have the time for answering question using a limited form of media like e-mail.

And when working on something important to you and you don't know what you're doing? Join this forum and ask questions first before you start "touching" the thing that is important to you let along smearing products onto it.


:dunno:
 
I saw this thread a few days ago but didn't have the time then to type out a reply.

My experience with Lexan has been in buffing motorcycle windshields. I do a fair amount of motorcycle details, and have buffed a fair amount of motorcycle windshields with varying success. Often, the UV coat on the windshield fails and has to be removed so it's not uncommon to have to buff that off.

I recently detailed my Dad's Honda Gold Wing for him to sell it. He had some scratches of varying depths on the windshield and wanted to see what I could do with it. The UV coating was barely beginning to flake. The windshield was Lexan. Here are the steps I took:

Started with buffing with my G100 and a 3.5" Lake Country Microfiber cutting pad with M105. This made good progress but of course left hazing. That's fine, I was trying to get the major scratches out. The UV coating was buffing off too, of course. I continued with this on both sides of the windshield until all of the UV coating was gone (took the windshield off to get to the back side better).
At this point most of the deep scratches were out but I was still left with two deeper scratches I wanted to get out better. I did some testing with very fine wet-sand paper, but it still wasn't quite "cutting" it. So I switched to 700 grit, then I went to 1000, and on up in steps to 3000. Once I got to that point, I switched back to M105 on the 3.5" LC MF cutting pad. This removed the sanding marks, and the scratches were as removed as I was going to get them (greatly improved and only noticeable if you were looking for them and knew where they were).

At this point I was left with hazing from the M105. This was where it took a lot of testing. I tried several different pads - fine cut, polishing, low density foam, medium density foam, high density foam. After a lot of trial and error I found that M205 with a 3" Lake Country foam pad did the trick. The foam pad was not purchased from AutoGeek (sorry), but it had a pretty fine cut with high density foam. For some reason, the high density foam was what made the difference. Nothing else wanted to work. This cleared up the hazing and left the windshield crystal clear.

Yes, the UV coating has been removed (it was already pretty much shot anyways). In my experience, and speaking with friends that also ride, that pretty much happens with older windshields and I have yet to see adverse effects from buffing it off. I did end up applying a sealant to the windshield to protect it (NXT Tech Wax 2.0, if I remember correctly). In the past I've also used PlastX at this stage as, if I remember correctly, it has some UV protectant. I usually wax it also though.

This whole process took a lot of time. I'm not sure exactly how long as I did a full detail on the motorcycle. I would have to guess a few hours, though. Granted, I had to do a lot of testing, and also once I buffed out the sanding haze the first time I realized I had missed some marks from the 700 grit sandpaper and had to go over it again. Argh.

To answer the question in advance, no, I'm sorry but I don't have any pictures.

Edited to add: I used the G100 on speed 5 or 6. The downside is, I had to stop relatively often to allow the windshield and pad to cool down. This added to the time significantly.
 
I meant to add two more things also:

I would have to guess there are different types of Lexan, or perhaps different coatings on them like was mentioned above. I've never tried to polish out Lexan on a car, only on motorcycle. I don't even know if all of the motorcycle windshields I've polished were Lexan - I only knew on this one because it said it was. So I'm not disputing what Mike said, I'm just adding my feedback from a motorcycle windshield standpoint.

The second note is, I can also tell you that, even though/if Lexan is also used on headlights, Meguiar's Keep Clear Headlight Coating is difficult, maybe impossible, to spray on clear enough to use to replace the coating on a motorcycle windshield. Just saying. (Nothing ventured, nothing gained, and it buffed off with M105).
 
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