Polishing Headlights (nb8a)

[japester]

In some previous discussions, I mentioned that I was going to try a polishing kit on my sun damaged headlights. I can now upload the photos and give a summary of how it works.

In short, try it.
$50 for the polishing kit certainly beats the $400 that mx5mania asks per headlight. If it doesn't work to your satisfaction, then it's not a significant hit to the pocket.

The kit contains:

• cleaning spray (concentrated glass cleaner)
• cutting compound
• glass sealing fluid
• wet'n'dry sandpaper (400, 600, 1000, 1500, 2000 grits)
• two white polishing cloths
• one blue sealant applicator cloth

Of everything in the kit, the only thing that I don't know where to source is the glass sealing fluid, but boy oh boy, that is the essential part in the kit.
The process is summarises as follows:

Extra things to make the job easy:

• Bucket of water (200mL is plenty)
• Two chux cloths
• chamois
• Camera

The water is for dipping your wet'n'dry paper into (to keep it, well, wet)
Get one chux damp/wet for wiping off the sanding slurry, the other to dry the glass, and the chamois to really dry the glass.
The Camera is to record your triumph

Process

• Clean
• Sand, going from coarse (400) through the grits to ultra fine (2000)
• Cut
• Clean
• Seal
• Admire your handiwork

I'll add in the major steps, one per comment.
(They'll all be in tonight, so if other comments can be added once they're all in that'd be nifty)

Photo set is up on flickr for the non-readers amongst us

[japester]

So, on to the headlights.
This is what they looked like before I started.

Left Hand Headlight. Noticeable damage, but not significant.


Right Hand Headlight. Notice the significant yellow fog on the upper surface?
Definitely impairing the ability of light to get out.

[Old Dude]

Nice job, very impressive

[japester]

Cause they're so much easier to work on when they're not in the car.
Two bolts on each headlight and some enthusiastic wiggling, and they come out.

[japester]

Take your pieces of sandpaper and line them up in a row. You don't want to get them mixed up. The roughest grit (400) is for taking off the surface of the glass, and as much of the fogged glass as you can. The others are for removing all the scratches the 400 grit paper leaves in your glass.

This part of the process is pretty much:

• Sand
• Wipe off slurry and check (wet chux)
• Check
• Sand some more
• Wipe (wet chux)
• Dry (dry chux)
• Dry again (chamois)
• Move up a grit level

Hints:

• Don't use too much water. You want just enough to lubricate the paper, and let it form a slurry. That slurry helps you. Having it all just fall off the glass, wastes your time and energy.
• Ensure that you sand the entire surface of the glass to the same level of roughness. If it's even, then the next grit won't have to work so hard.
• For the truly paranoid, replace the water after every grit level. (I only bothered once I made if past 1000) This is to make sure you don't transfer any of the coarser grits onto your finer papers.

You will notice that as you get through to the finer grits of paper, that the glass gets almost transparent. The manner in which the water beads on the surface is a very good indicator of how consistent you are being.

400 grit:
hmmmm scratches hmmmm


1000 grit
Note the area on the left that needs some more work


2000 grit
You should be able to see the clarity gradually increasing with each level of fineness. The difference between 400 and 2000 is readily apparent here. The glass is almost, almost usable.

[japester]

Once you're done sanding, it's time to make even finer scratches in your glass.

Do it the same way you'd use cutting compound on your paint. Small dabs of goop, rub in circles, wipe it off. Do it again.
I tried for sections about 10x10cm. That seemed to work.
This step took me two passes to get to a level that I was comfortable with. I was tempted to do more, but I didn't want to run out of compound.

Cut Glass
I put it in the car, because now, I could actually consider using this lens.

[japester]

This step uses that little bottle that makes this kit worthwhile. All the previous steps had me slowly going, "yeah, this appears to be working." Once I'd applied the sealer, the glass just popped.

This stuff goes on very thin, and goes tacky pretty quickly. Get it wiped on quickly, and then DON'T TOUCH THE GLASS!
I must repeat those last words, so you don't repeat my mistake. DON'T TOUCH THE GLASS!

The instructions say it takes about an hour to dry. It lies. Leave it overnight. If you have a dust and bug free environment, even better.

You might consider applying two coats. I did, so I could get rid of the smudge my jacket left on one headlight when I touched it before it was dry. Leave it several hours before you consider applying the second coat. There is more than enough sealant. (there's probably enough for 8 headlights, though the kit says it does 4)

Polished and Sealed glass

[japester]

With the headlights back in the car, we can do the comparisons.

I didn't really notice just how well they turned out until I looked at the before and after photos.
The left headlight came up really well. I'd consider it very close to original quality.
The right hand headlight, not so much. There is still some milkiness in the glass which is apparent when the lights are on. Given how much of an improvement over the yellow nastiness that it was before, I'm very happy with the outcome.
I think that the milkiness came from not enough sanding with the 400 grit, being that I didn't remove all the damaged glass.

Left Headlight


Right Headlight


Right Headlight - low beam

[bensale]

Wow

Great work mate!!! =)

[de Bounce]

Great outcome and much cheaper than replacing them.

[Mr Morlock]

the lense is polycarbonate- glass is now old technology. The lenses are hard coated either by spray painting or flow coating- I think most of the Japanese manuf used the former system. I reckon that would be a vital part of the end process in the kit- the right product to do a reno. Good result and very good photos etc.

[CoachOz]

Thanks for the post - now I know how to clear the lenses on my wife's BMW wagon

[BadBong]

Great post mate. Tried to do something similar but ended up with the same problem as you've had encountered with your right headlight (didn't spend enough time on 400).

Mind telling us where you got the 'kit' from?

[Okibi]

Great post, thanks for sharing!

[japester]

Mind telling us where you got the 'kit' from?

No problem at all! Picked it up from Repco, for something slightly less than $50.
Looks something like this

there is enough lens sealant to cover a lot of headlight. At least 4. There may be enough sandpaper and cutting compound to do 4 headlights, but these parts are easily obtainable from other sources for small amounts of $$$.