[General] Headlight Restoration

[Fu Manchu]

Firstly, this thread is not about how WD40, toothpaste or hairspray are some bullshit miracle fix to yellow UV affected polycarbonate lights and works perfect. You’d have to be blind or accepting of poor workmanship. Don’t post about it. Get back in the sea with your click bait solutions.

The lights aren’t too bad but the coating has started to go and the left one has some nasty damage to the indicator area.

We can fix that.

Yeah, you can do it with the lights on the car but to do a proper job, take 10mins to remove the bar and remove the lights. It’s easy. Don’t be lazy. VE and VF is about the same and is also easy.

One has sugar soap. The other water. No hose needed. Pump them up and get it done. That brush is from Bunnings in the paint aisle. It’s had one hell of a workout and continues to perform. $15 well spent.

Now. While we have the brush and water there, get in and clean that grot up. Behind the bar is going to be yuck. No excuses for not taking 15mins to do something about it.

*Warning! I did this job completely naked so don’t go looking at the reflections too closely.

 

[Fu Manchu]

First thing is using the brush, give the whole headlight assembly a clean. Sugar soap and work the brush into the little nooks and crannies. Rinse and the grab the sanding block or DA sander.

I started here with 240 grit dry sand with the DA. I had to focus on working out the deep scratches and that damaged area on the indicator I mentioned.

You can see the coating coming away

Left with this

 

[Fu Manchu]

As you go always rinse down with sugar soap and work the brush in to clean the surface and get the schmutz away from the surface as you sand. I also use the sugar soap as a lubricant when wet sanding.

First wet sand is 800 grit. Rinse with clean water and continue.

1000 grit next. Same procedure. I’m using a cork sanding block. Keep an eye out for remaining imperfections and work those spots a bit more. I do horizontal, vertical and rotating motions while… sanding.

I also did a 3000 grit pass but I’ve lost the photo.

 

[Fu Manchu]

Next is some work with the cone. Then get a foam cone and put it on the drill to polish the headlight. I was using this one to polish the road line markings in our street but it’s still good for this job.

My choice of polish is Maguiars Plastic Polish.

This is a blue medium firmness cone. Then I used the red soft cone with plastic polish. Wipe down with a clean microfibre often to clear off residue.

 

[Fu Manchu]

Next wash it down again with sugar soap and the brush. All of it. Front and back. Rinse with clean water. Then blow the water off with a blower or compressed air. Dry. Then with a new microfibre cloth, wipe the lense carefully with some IPA lightly sprayed onto the cloth. I let it air off a bit because that stuff can mess up plastics. (It messes me up too so I’m going have to stop sipping it.) It get the waxes off before applying the coating.

 

[Fu Manchu]

So here we are. You have to coat the polycarbonate to make sure it doesn’t go yellow.
Options here are ceramic coating every year, careful application with 2K UV resistant clear coat (only for spray painters because the catalyst could react with the polycarbonate), UV resistant acrylic clear…

or my go to product. $15-$20 from Repco. Have to ask for it over the counter. It won’t be on the shelf.

*Make sure it’s not going to rain, or the retic is not going go on. Make sure no one is waving a garden hose around.

 

[Fu Manchu]

This stuff is best described as thick water in its consistency. Spray on and it runs down and evens out. I also treat the back of the lights to limit the plastic degrading. Everyone’s does.

Cover the indicator pins with tape. Cover the headlamp wiring plug with tape.

When you spray it, make sure you do what you can to keep dust at bay. Wet the ground down, wait for no wind or give the area a bloody good clean down before you start. Get the lights up off the ground.

I sprayed mine on the bins with a base of clean cardboard on top.

Yes bits of dust will get in. It’s ok. Leave it. Don’t touch it. Do another heavy coat later. 20-30mins is what I waited. It drips a bit off the light so again, don’t worry about it.

I leave them a few hours before moving them. Over that time, imperfections will slowly disappear and be hardly noticeable. If you do this in a spray booth, dust won’t be an issue.

I also remove the vent tubes for a clean and treatment of Aerospace 303. Spray it in a bag and let soak. Those with a keen eye will see there are more than the headlights have here. This is because I also did another set at the same time.

 

[Fu Manchu]

After.

Job done.

*edit: Make sure you plug the lights back in. I forgot the passenger side.
Off comes the bumper tomorrow.

 

[Fu Manchu]

How a headlight is made.

 

[Skylarking]

Love the write-up and pictures

It would have been far better if the polycarbonate lens was bolted or screwed to the main headlight body and the lot sealed with a big o-ring. Then a new lens could be made available for purchase at a reasonable price but for designed obsolescence

Such a bolted arrangement would also have made it much easier to do upgrades to halo rings (if that’s your thing) or LHD to RHD conversions of the Chevy SS HID headlight assemblies for use in our commodores, etc…

At the moment, being as it is, sanding polishing and recoating is the only cost effective solution for us “normals” And you’ve done a great (OCD respected) job at reco-ing your headlamp assemblies

PS: liked the manufacturing video except the last bit about how easy it is to change of globes by popping the bonnet and going in from the rear of the headlamp assembly - who are they kidding