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Refinishing headlights using SEM21013

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  • Refinishing headlights using SEM21013

    First of all, this is not G2-specific... Though depending on how well it stands up, I may do the same thing to the one pieces.

    This was performed on my daily driver because they were looking like crap.

    My brother bought this stuff from our local paint shop because it caught his eye. We've used SEM products before and they tend to perform great. He ended up refinishing his CTR headlights with this product, but his car is literally not driven, so we have not seen how it stands up to daily sun/UV exposure.

    http://www.semproducts.com/solaray-uv-clearcoat/

    That's the stuff.. SEM Product#: 21013

    I forgot to snap a picture of the instructions, but they are picture-based and infer that you:
    1) Clean the surface with soapy water
    2) 400 grit wet sand
    3) 1500/2000/3000 grit wet sand
    4) 2min flash-time between coats
    5) 5min dry time
    6) UV heat lamp (or direct sun light, obviously)

    I thought that 3000 was a bit too smooth... being a painter I tend to want a slightly rougher surface to ensure that the new material bonds well.. it has a nice surface to "hold on to".

    So what I did was 400/800/1200/2000 wet, making sure to get all of the stock UV coating off... its quite obvious once you're through it and when its all off.

    Then clean the housing... mask off whatever you need to mask off... use a wax/grease remover, not an acetone/thinner product as the lens will melt and the surface will not be even enough to spray over.

    Admittedly I messed up on the first light. After two coats I put it in the sun for about 4 minutes. Then got it in the shade and did another coat. The UV exposure was enough to not let the third coat melt into the first two coats. This left a slightly textured surface. The closest thing I could relate it to is like a high-quality screen protector for your phone.... not 100% opaque, but close.

    The second light turned out better as I laid all the coats down before putting it outside. I sprayed it pretty heavy to make it 'flow' out and not have a spattered or textured finish. With about 2-3 min flash time between coats.

    After about 10min in the sun they were pretty damn dry. But I let them sit out there for about 20min, rotating them to make sure all sides and angles got good exposure.

    It's and odd product in the sense that the material that was on plastic was dry to the touch... but the overspray on the masking paper was still tacky. So its definitely a material designed for plastic, and its activated/hardened by sunlight.

    On to the pictures!

    The light on the left is how it looked untouched. The one on the right is after the four step sanding process.



    Before:



    Sanded:



    Sprayed, installed:



    Sprayed:



    After:



    After:




    After:



    So as I said at the start, there long-term durability has yet to be seen... But if the cost, and general reputation of quality are any indication, it should be a relatively long-lasting cure for hazy and dull headlight lenses.

    Of course some lights that leak and fog up etc need to be opened and completely re-sealed using butyl tape. That was not needed this time around, so that's a whole other subject.

    Either way this should help out if anyone is wanting to refinish theirs.

    If you wanted you can polish them out after the sanding process, rather than spending the money on the product... but without the UV coating, the plastic will age and yellow fairly fast. You could keep them waxed and very clean and they will last even longer.. But hopefully THIS is an even longer lasting remedy.

    Opinions, advice, criticism and questions are all welcome.
    Last edited by unified112; 18 May 2014, 04:15:17.

  • #2
    Those look great. So you just sprayed right onto the hazy sanded lenses? I know you never mentioned polishing them but it's crazy that it can become so clear by just spraying on a product. The pics don't lie. I might have to try these on my one pieces. Thanks for the write up.

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    • #3
      Didnt read any of it and just looked at the pictures but, isnt the plastic ised on our headlights completely different than the plastic of modern lights?

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      • #4
        Originally posted by fgo4 View Post
        Those look great. So you just sprayed right onto the hazy sanded lenses? I know you never mentioned polishing them but it's crazy that it can become so clear by just spraying on a product. The pics don't lie. I might have to try these on my one pieces. Thanks for the write up.
        Yep, sprayed right over the 400/800/1200/2000 scratches.

        The material is clear... It fills all of the scratches and produces a wet, clear film over the top.. That's why you have to have FINE scratches. If you tried to spray over 400 grit scratches, you'd see them under the clearcoat.

        It's the exact same principal as spraying clearcoat on automotive paint.

        As I said in the post about the new material having something to grip on to. If you spray clear coat onto a polished surface, how would the new material stick to the lense? You would have adhesion problems and it would peel off.

        While paint and clear also bond chemically (by melting into each other) a BIG part of adhesion is also the surface. If it's prepped well (smooth, even scratches... Not patches of 400 or 800 leftover) then it will adhere well.

        Originally posted by DA_all_day View Post
        Didnt read any of it and just looked at the pictures but, isnt the plastic ised on our headlights completely different than the plastic of modern lights?
        I'm not going to pretend like I know the exact material (polyethylene, polypropylene, etc) that our one pieces are, versus the makeup of the Saab lenses....

        But the plain fact is, they are all plastic. This material is designed for plasticS... The can nor the directions state that it is designed just for one type of plastic.

        Whether it's the "right" way to restore a one piece or not, I can't say 100%.... Though I willsay tthat using automotive clearcoat is even less proper than using this material.

        Automotive clear isn't meant to be applied as a top coat over plastic. It just isn't. It's meant to go over paint. Which is why some people have had peeling or other adhesion issues with automotive clear over headlights. You can use an adhesion promoter that is make for plastics, but having multiple types of product on top of the lense will make it that much more difficult to achieve a crystal clear outcome.
        Last edited by unified112; 18 May 2014, 15:54:49.

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        • #5
          Four months later after baking in the sun all day, every day.. really don't wash the car as much as I should, but the lights are still fresh and clear.. save for some bug splatter :/

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          • #6
            Good stuff, might have to try this on my DA one piece headlights

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            • #7
              1+yrs later..

              Car still doesn't get garaged, nor do I wash it as much as I should.

              Lights are still crystal!

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              • #8
                Glad to see it's holding up, especially since you cured it with sunlight instead of a lamp. I wonder if it's worth forking over the $40+ for a can of this stuff for my Impreza's headlighs or if I should just do like I did with my DA lights and spray some standard automotive clear with an HVLP (since I already have some clear left in the garage).
                Track Project DB2 #896
                LeMons Project DA9
                My OG DA9, Wrecked, Stripped, R.I.P

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                • #9
                  I've just never had good luck with automotive clear on headlights. But hell, you have the stuff.. with adequate prep it should turn out good.

                  Yes this SEM stuff surely is not cheapby any means. Should get two sets of headlights out of one can though.

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