Monday 3 December 2018

Restoring Plastic Headlights


Plastic headlights on modern cars tend to fade to yellow and become very milky over time. Milky yellow lights are much dimmer than clear new lights, but because this happens over a long time most owners don't notice the lights getting worse.

Picture of light before restoration


You need to be brave to tackle this as the lights are going to look a whole lot worse before they look better. If you are brave it's fairly easy to make a huge improvement to the lights in less than 2 hours even without power tools. There are some disadvantages, and I'll mention this later.

The aim is to completely remove the original degraded factory coating, there is just one way to do this and it seems extreme. Sand it off.

Mask round the light so you don't damage the paint, I used insulating tape. BUT wax polish the paint first so the tape does not lift the lacquer when it's removed (yes I learnt this the hard way).

Use 600 grade wet and dry and use it wet with slightly soapy water, no power tools, just round and round, back and forth until the whole light is evenly matt.

Move on to 1500 grade wet and dry, and again use it wet until the whole light is smooth but still matt

Picture of light after sanding with 600


The next bit is easier with a 50mm finishing sponge and a low speed drill, but I have done them by hand, it just takes longer. Use G3 finishing compound (from a car paint shop) and polish the light until is is clear and all the matt finish from the 1500 appears to be gone. It will now look pretty good but just a tiny bit dull or matt.

Use T-cut or similar super fine cutting compound in the same way as you did the G3, and then finally use a high quality war polish to protect the surface.

The lights will look pretty much like new, and the first time you drive in the dark you will amazed at how much better they are.

Light after polishing


Now the disadvantage. The original coating was put on the light by the factory to stop the plastic getting dirty as the surface of the plastic is slightly porous. The coating has gone, you have no protection, so you will have to clean the lights far more often. A good wax polish seems to offer good protection for many weeks.