Using an RO90 to Polish Plastic Headlight Covers

HarveyWildes

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[member=44099]Cheese[/member] mentioned this in another topic as a use for an RO90.  I have a truck that needs it badly.

Assuming that I just have an RO90 with what comes in the systainer, what set of accessories/abrasives would I need to do a good job of this?

Another application I have is a plastic BMW motorcycle windscreen that has gotten hazy over the years.  Can I use the RO90 to polish the windscreen to the optical clarity needed for riding?  If so, would it require a different set of accessories/abrasives.
 
Polishing compounding from Turtle Wax worked well on my Tundra using an old T-Shirt, I hadn't thought of

using my R90.

 
I used a platin 500-1000-2000-4000 combo, spraying water on the surface to keep it lubricated (or the abrasive pad just clogs and burns up).  I might have been able to skip the 4000, but since I had it, I just used it.  Following that, menzerna FG400 and a fine polish to follow.  The polishes were applied with medium and fine foam pads respectively. 

But, it will re-haze in 6 months unless you apply a UV resistant coating. 
 
It depends upon the condition of the plastic. If it’s just hazy you could start with rubbing compound.

If you can’t see inside the headlight and it has a yellowish cast, then you’re better off with paper. Take your thumb nail and if you can scratch stuff off with your nail, you’re beyond the compound stage. At that point I’d start with 220/240/280/320 and see how that works. It’s mandatory to cut through the crust on the top and reach virgin material, otherwise it just hazes up again in 4-5 months.

Just like sanding wood, run through the grits. Something like 220-320-500-800-1200-2000, something like that. Once I hit the 500 area, I like to spritz a little water on it to act as a lubricant. Finish with a nice buff.
 
You might want to review this thread regarding polishing out headlight covers.  I have adapted my process for polishing out solid surface countertop material to polishing headlight covers.  I also find it helpful to cover adjacent painted surfaces with blue painter's tape and cover that with aluminum duct tape.  The blue painter's tape releases well, but has little abrasion resistance while the covering aluminum tape has great abrasion resistance with a very aggressive adhesive.  I'll attach my schedule of abrasives for solid surface material for reference.  The basis of this document is the solid surface class material created by Steve Bace of Festool in Henderson.  Be sure to use the 50/50 spray mix of denatured alcohol and water to clean the lenses between grits to remove residual abrasive material. 

Edit: Attached the correct reference document.  Sorry about the boo-boo. 
 

Attachments

The 50/50 mix of alcohol and water must be good as Willy says but don’t use straight denatured alcohol. I’ve seen it cause fractures in thick machined acrylic.
 
Sparktrician said:
I'll attach my schedule of abrasives for solid surface material for reference.  The basis of this document is the solid surface class material created by Steve Bace of Festool in Henderson. 

Hey Sparky, the download doesn't include your abrasive schedule.  [tongue] The download I get is just a discussion of the upcoming class.
 
Cheese said:
Sparktrician said:
I'll attach my schedule of abrasives for solid surface material for reference.  The basis of this document is the solid surface class material created by Steve Bace of Festool in Henderson. 

Hey Sparky, the download doesn't include your abrasive schedule.  [tongue] The download I get is just a discussion of the upcoming class.

Thanks for the catch, [member=44099]Cheese[/member].  The correct one is now attached.  [smile]
 
Michael Kellough said:
The 50/50 mix of alcohol and water must be good as Willy says but don’t use straight denatured alcohol. I’ve seen it cause fractures in thick machined acrylic.

I've not noticed any problems with the 50/50 mix.  The good thing is that it cleans well and dries faster than water alone. 
 
Sparktrician said:
Thanks for the catch, [member=44099]Cheese[/member].  The correct one is now attached.  [smile]

Thanks for that Sparky...lots of good info in that .pdf, especially on the high gloss section. [big grin]
 
Hey [member=7493]Sparktrician[/member] & [member=44099]Cheese[/member], thanks for all of the info.  This will give me a good start on the headlights - now I just have to get the RO90 :).

Any thoughts on polishing my BMW motorcycle windscreen?  It is some kind of plastic, not sure what - I'm not even sure if it is the original or aftermarket.  There is some kind of very thin coating that has been peeling off since I got the bike several years ago.  It is mildly irritating but doesn't get in the way most of the time.  In strong sun glare the windscreen picks up the light where the coating has peeled, and I have to look over the windscreen in its low position.  Given its current condition, it's hard to imagine that I could screw it up any worse, but...  Since replacement windscreens are pretty expensive, I could come close to paying for the Rotex if I could use it to repair the windscreen.
 
HarveyWildes said:
Any thoughts on polishing my BMW motorcycle windscreen?  It is some kind of plastic, not sure what - I'm not even sure if it is the original or aftermarket.  There is some kind of very thin coating that has been peeling off since I got the bike several years ago.  It is mildly irritating but doesn't get in the way most of the time.  In strong sun glare the windscreen picks up the light where the coating has peeled, and I have to look over the windscreen in its low position.  Given its current condition, it's hard to imagine that I could screw it up any worse, but...  Since replacement windscreens are pretty expensive, I could come close to paying for the Rotex if I could use it to repair the windscreen.

Hey Harvey, I'll ask my neighbor who knows and owns all things from BMW. Just curious if you own the K series?
 
Yep - 1999 KT1200LT

The BWM replacements are $700-$1000 roughly, depending on the size.  I can get aftermarket windscreens for $130-$500, not sure how to gauge quality, so thinking that amortizing in a Rotex might solve that problem.  I guess if it came down to it, I could always give it a try with the Rotex, and if it fails miserably, spring for a new aftermarket windscreen.  It's just that the Rotex seems more versatile in the long run.
 
Polishing headlights is fine, BUT don't expect it to last very long if the vehicle is exposed to the sun a lot. Sometimes they will turn hazy again in a couple of months *shrugs*
 
Peter_C said:
Polishing headlights is fine, BUT don't expect it to last very long if the vehicle is exposed to the sun a lot. Sometimes they will turn hazy again in a couple of months *shrugs*

Plastic head lights are covered with a UV protective coating to stop them getting "sunburnt" and turning yellow. If you polish them you have to reapply the coating. Should be available from auto supply shops.
 
Bohdan said:
Peter_C said:
Polishing headlights is fine, BUT don't expect it to last very long if the vehicle is exposed to the sun a lot. Sometimes they will turn hazy again in a couple of months *shrugs*

Plastic head lights are covered with a UV protective coating to stop them getting "sunburnt" and turning yellow. If you polish them you have to reapply the coating. Should be available from auto supply shops.
The OES headlights have a hard coating on them. Other than spraying on a proper coating, any kind of liquid UV protectant will require frequent re-application. After having seen polished headlights revert back to being hazy it has become common practice to just replace them with new at a very high cost.

Just wanted folks to understand polishing them only lasts so long, nothing more. I have polished my own as the vehicles aged.
 
Peter_C said:
Just wanted folks to understand polishing them only lasts so long, nothing more. I have polished my own as the vehicles aged.

Ya, I get about 2 years out of them if I do a really good job. If I rush it, I'll get maybe 4-5 months.
 
Scotty Kilmer recommends Meguiar's Headlight Cleaner and Coating:  He said clear coat spray doesn't last on headlights.  He only reapplied the Meguiar's Headlight Coating once a year in his test.
 
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