Why would you want to do such a thing?Your headlights are subjected to a barrage of road muck, UV light, road grit and stones which can chip and damage the surface of your lights. Oxidized or faded lights can produce poor visibility. Likewise scratches to your lenses "can effect the performance of your lights by up to 50%" (Osram).
I figured that since I have spent a fair amount of money on gathering the bits to do a xenon retro fit, I was going to make sure that they are going to give me optimal performance.
So I set about getting the equipment needed to wet sand my plastic headlamps.
What you will need:- Patience!
- Wet and dry sandpaper – Various grades depending on how severe your headlamps are damaged. If you want the best finish I would finish with at least 2500 grit.
Sandpaper grit depends on the severity of your lens damage. Which ever grit you choose to start with, you must also purchase 1 sheet of the higher number grit paper - up to what ever grit you are comfortable with to complete the restoration process. (I stopped at 2500.)
Example: If you start with 1000, you must also buy 1500 2000 and 2500.
If the headlamps have heavy damage you could go down to 800 or even 600 grit. However, remember that you should not skip more than one grade as you go through the grades of grit and the lower you go the longer the job. I am not recommending that you don’t go this low it’s just its going to take you longer.
I would use the following as a guide:
1 sheet of 1000 grit (to start with when working on severely oxidized and yellow lenses.)
1 sheet of 1500 grit (to start on not so yellow, but very cloudy / faded and or lightly swirled/scratched lenses.)
1 sheet of 2000 grit (starting with mostly clear, or barely cloudy lenses)
1 sheet of 2500 grit to finish off with (or continue on to 3000 if it makes you happy.) - 1 spray bottle (travel bottles with a spray head are ideal)
- If you are doing this whilst the headlamps are on the car then you will need 1 roll of your favourite masking tape, I would choose 3M blue 1" masking tape.
- 1 bucket - this needs to be large enough to soak your sheets of sand paper in. It doesn’t have to be big.
- A bottle of Meguiars Plastx or similar – This is used to finally finish the restoration and can be achieved with many low cut polishes. The more effective the product the easier it is going to be for you to finish the job. I have used Autosol in the past but it required more work than a machine polisher for example. For these lights I used Meguiars Speed Glaze with a machine polisher on a polishing pad.
- Microfibre cloths or similar for working the polish.
- A large pair of gonads – you will have to find these yourself!
The Method:1. First either take off the headlamps from the car or mask up the area around the headlamp. Remember you are going to use sandpaper near your paintwork here so use plenty of masking tape to protect your paint.
2. Fill your bucket of water. Tear up your pieces of wet and dry sandpaper (I tore mine into 4 from each sheet) and soak in the bucket of water to saturate the sheets (ONLY the grade you are going to be working with). This prevents some of the larger grits mixing with your other sheets. Leave them in the bucket of water for ten minutes (they will probably curl but don’t worry about this). I placed my headlamp off the floor on an upturned bowl to keep the water away from the inner parts of the headlight.
3. Take your spray bottle and put a little bit of car shampoo/fairy liquid in it together with some water to make a solution. Next take your first piece of wet and dry sandpaper and start to sand in ONE direction whilst applying very slight pressure. Choose 1 direction to sand in to start with, vertically or horizontally. (I chose vertical to start.) do NOT sand in a circle. It’s wise to completely clean the headlight with your cloth and fresh water when you change direction.
It’s really important to keep the headlight wet whilst sanding. Once it goes dry you will be scratching your lights. To give you an idea I refilled my spray bottle around 3 times per grade of grit with clean water and car shampoo.
Try to keep dipping your sanding sheet and hand into the bucket of clean water, this removes the debris caused by your sanding. You should see the water on the lights turn white as the plastic comes away from the lights.
4. Once you have sanded in both directions vertically and horizontally (I took about 10-15 mins per direction) its time to inspect your work. Clean off the headlamp with your clean cloth. And remember to change the water in your bucket.
At this point you are probably staring at you pride and joy thinking what have I done!!
Don’t give up at this stage – You can’t go back!
5. Now proceed to the next higher number grade and repeat the process. Keep doing this until you can feel very few imperfections and can see very little scratches on the lenses. The better you get this the less work it will be on the final polishing stage.
It’s hard to judge when to move to the final stage but time spent on the job is a better indicator. My headlamp restoration took me about 2 hours per headlight – did I mention at the start of this that you need patience!!
Now clean up the light and progress to the final stage.
The Final Stage
6. Depending on your preference use a machine polisher and pad, or get your Plastx, Autosol or similar out and apply to the headlamp with your microfibre. You will need to really work at this to remove the fine scratches left from your final grade of wet and dry sandpaper. Again the more work you put into this, the better the results.
You should then be left with something like this:
And after some more work the finished headlamp:
7. It’s wise to now seal up your headlamp with a wax or sealant for protection. I used Collinite 476 but any polish/wax will do.
Now the disclaimer – if you embark on this task then as soon as you start with the first grit paper you will be adding scratches to your lights. It’s only through your hard work that you will keep reducing these to a level where you can no longer see the scratches and will have removed all the imperfections that you have started with. I used a machine polisher for the final stage. This radically reduced the time spent on the final stage.
Put aside a morning/afternoon to do each light then you will do a better job. Always keep the headlamp/sandpaper wet and keep your bucket of water clean.
I achieved the removal of some fairly deep scratches by taking my time. I am no expert or bodyshop specialist, just a normal bloke who likes to give things a go. I was really happy with the results.
Bodger
